Pilot/Controller Glossary Basic

6/17/21 Pilot/Controller Glossary PILOT/CONTROLLER GLOSSARY

PURPOSE a. This Glossary was compiled to promote a common understanding of the terms used in the Air Traffic Control system. It includes those terms which are intended for pilot/controller communications. Those terms most frequently used in pilot/controller communications are printed in bold italics. The definitions are primarily defined in an operational sense applicable to both users and operators of the National Airspace System. Use of the Glossary will preclude any misunderstandings concerning the system’s design, function, and purpose. b. Because of the international nature of flying, terms used in the Lexicon, published by the International Civil Aviation Organization (ICAO), are included when they differ from FAA definitions. These terms are followed by “[ICAO].” For the reader’s convenience, there are also cross references to related terms in other parts of the Glossary and to other documents, such as the Code of Federal Regulations (CFR) and the Aeronautical Information Manual (AIM). c. This Glossary will be revised, as necessary, to maintain a common understanding of the system. EXPLANATION OF CHANGES d. Terms Added: AERONAUTICAL INFORMATION SERVICES (AIS) CERTIFICATE OF WAIVER OR AUTHORIZATION (COA) FLYAWAY HIGH UPDATE RATE SURVEILLANCE REMOTE PILOT IN COMMAND (RPIC) SELF−BRIEFING SMALL UNMANNED AIRCRAFT SYSTEM (sUAS) VISUAL OBSERVER (VO) e. Terms Deleted: ARINC NATIONAL FLIGHT DATA CENTER (NFDC) f. Terms Modified: DOMESTIC NOTICES FLIGHT PLAN FLIGHT SERVICE STATION (FSS) ICING INTERNATIONAL NOTICES g. Editorial/format changes were made where necessary. Revision bars were not used due to the insignificant nature of the changes.

PCG−1

6/17/21 Pilot/Controller Glossary A

AAI− ACLT− (See ARRIVAL AIRCRAFT INTERVAL.) (See ACTUAL CALCULATED LANDING TIME.) AAR− ACROBATIC FLIGHT− An intentional maneuver (See AIRPORT ARRIVAL RATE.) involving an abrupt change in an aircraft’s attitude, an abnormal attitude, or abnormal acceleration not ABBREVIATED IFR FLIGHT PLANS− An necessary for normal flight. authorization by ATC requiring pilots to submit only (See ICAO term ACROBATIC FLIGHT.) that information needed for the purpose of ATC. It (Refer to 14 CFR Part 91.) includes only a small portion of the usual IFR flight plan information. In certain instances, this may be ACROBATIC FLIGHT [ICAO]− Maneuvers inten- only aircraft identification, location, and pilot tionally performed by an aircraft involving an abrupt request. Other information may be requested if change in its attitude, an abnormal attitude, or an needed by ATC for separation/control purposes. It is abnormal variation in speed. frequently used by aircraft which are airborne and ACTIVE RUNWAY− desire an instrument approach or by aircraft which are (See RUNWAY IN USE/ACTIVE RUNWAY/DUTY on the ground and desire a climb to VFR-on-top. RUNWAY.) (See VFR-ON-TOP.) (Refer to AIM.) ACTUAL CALCULATED LANDING TIME− ACLT is a flight’s frozen calculated landing time. An ABEAM− An aircraft is “abeam” a fix, point, or actual time determined at freeze calculated landing object when that fix, point, or object is approximately time (FCLT) or meter list display interval (MLDI) for 90 degrees to the right or left of the aircraft track. the adapted vertex for each arrival aircraft based upon Abeam indicates a general position rather than a runway configuration, airport acceptance rate, airport precise point. arrival delay period, and other metered arrival ABORT− To terminate a preplanned aircraft aircraft. This time is either the vertex time of arrival maneuver; e.g., an aborted takeoff. (VTA) of the aircraft or the tentative calculated landing time (TCLT)/ACLT of the previous aircraft ACC [ICAO]− plus the arrival aircraft interval (AAI), whichever is (See ICAO term AREA CONTROL CENTER.) later. This time will not be updated in response to the ACCELERATE-STOP DISTANCE AVAILABLE− aircraft’s progress. The runway plus stopway length declared available ACTUAL NAVIGATION PERFORMANCE and suitable for the acceleration and deceleration of (ANP)− an airplane aborting a takeoff. (See REQUIRED NAVIGATION ACCELERATE-STOP DISTANCE AVAILABLE PERFORMANCE.) [ICAO]− The length of the take-off run available plus ADDITIONAL SERVICES− Advisory information the length of the stopway if provided. provided by ATC which includes but is not limited to the following: ACDO− (See AIR CARRIER DISTRICT OFFICE.) a. Traffic advisories. b. Vectors, when requested by the pilot, to assist ACKNOWLEDGE− Let me know that you have aircraft receiving traffic advisories to avoid observed received and understood this message. traffic. ACL− c. Altitude deviation information of 300 feet or (See AIRCRAFT LIST.) more from an assigned altitude as observed on a ACLS− verified (reading correctly) automatic altitude (See AUTOMATIC CARRIER LANDING readout (Mode C). SYSTEM.) d. Advisories that traffic is no longer a factor.

PCG A−1 Pilot/Controller Glossary 6/17/21

e. Weather and chaff information. ADVISORY FREQUENCY− The appropriate fre- f. Weather assistance. quency to be used for Airport Advisory Service. (See LOCAL AIRPORT ADVISORY.) g. Bird activity information. (See UNICOM.) h. Holding pattern surveillance. Additional ser- (Refer to ADVISORY CIRCULAR NO. 90-66.) vices are provided to the extent possible contingent (Refer to AIM.) only upon the controller’s capability to fit them into the performance of higher priority duties and on the ADVISORY SERVICE− Advice and information basis of limitations of the radar, volume of traffic, provided by a facility to assist pilots in the safe frequency congestion, and controller workload. The conduct of flight and aircraft movement. controller has complete discretion for determining if (See ADDITIONAL SERVICES.) he/she is able to provide or continue to provide a (See LOCAL AIRPORT ADVISORY.) service in a particular case. The controller’s reason (See RADAR ADVISORY.) not to provide or continue to provide a service in a (See SAFETY ALERT.) particular case is not subject to question by the pilot (See TRAFFIC ADVISORIES.) and need not be made known to him/her. (Refer to AIM.) (See TRAFFIC ADVISORIES.) AERIAL REFUELING− A procedure used by the (Refer to AIM.) military to transfer fuel from one aircraft to another during flight. ADF− (Refer to VFR/IFR Wall Planning Charts.) (See AUTOMATIC DIRECTION FINDER.) AERODROME− A defined area on land or water ADIZ− (including any buildings, installations and equip- (See AIR DEFENSE IDENTIFICATION ZONE.) ment) intended to be used either wholly or in part for the arrival, departure, and movement of aircraft. ADLY− (See ARRIVAL DELAY.) AERODROME BEACON [ICAO]− Aeronautical beacon used to indicate the location of an aerodrome ADMINISTRATOR− The Federal Aviation Admin- from the air. istrator or any person to whom he/she has delegated his/her authority in the matter concerned. AERODROME CONTROL SERVICE [ICAO]− Air traffic control service for aerodrome traffic. ADR− AERODROME CONTROL TOWER [ICAO]− A (See AIRPORT DEPARTURE RATE.) unit established to provide air traffic control service ADS [ICAO]− to aerodrome traffic. (See ICAO term AUTOMATIC DEPENDENT AERODROME ELEVATION [ICAO]− The eleva- SURVEILLANCE.) tion of the highest point of the landing area. ADS−B− AERODROME TRAFFIC CIRCUIT [ICAO]− The (See AUTOMATIC DEPENDENT specified path to be flown by aircraft operating in the SURVEILLANCE−BROADCAST.) vicinity of an aerodrome. ADS−C− AERONAUTICAL BEACON− A visual NAVAID (See AUTOMATIC DEPENDENT displaying flashes of white and/or colored light to SURVEILLANCE−CONTRACT.) indicate the location of an airport, a heliport, a landmark, a certain point of a Federal airway in ADVISE INTENTIONS− Tell me what you plan to mountainous terrain, or an obstruction. do. (See AIRPORT ROTATING BEACON.) ADVISORY− Advice and information provided to (Refer to AIM.) assist pilots in the safe conduct of flight and aircraft AERONAUTICAL CHART− A map used in air movement. navigation containing all or part of the following: (See ADVISORY SERVICE.) topographic features, hazards and obstructions,

PCG A−2 6/17/21 Pilot/Controller Glossary navigation aids, navigation routes, designated f. Instrument Departure Procedure (DP) Charts− airspace, and airports. Commonly used aeronautical Designed to expedite clearance delivery and to charts are: facilitate transition between takeoff and en route operations. Each DP is presented as a separate chart a. Sectional Aeronautical Charts (1:500,000)− and may serve a single airport or more than one Designed for visual navigation of slow or medium airport in a given geographical location. speed aircraft. Topographic information on these charts features the portrayal of relief and a judicious g. Standard Terminal Arrival (STAR) Charts− selection of visual check points for VFR flight. Designed to expedite air traffic control arrival Aeronautical information includes visual and radio procedures and to facilitate transition between en aids to navigation, airports, controlled airspace, route and instrument approach operations. Each permanent special use airspace (SUA), obstructions, STAR procedure is presented as a separate chart and and related data. may serve a single airport or more than one airport in a given geographical location. b. VFR Terminal Area Charts (1:250,000)− h. Airport Taxi Charts− Designed to expedite the Depict Class B airspace which provides for the efficient and safe flow of ground traffic at an airport. control or segregation of all the aircraft within Class These charts are identified by the official airport B airspace. The chart depicts topographic informa- name; e.g., Ronald Reagan Washington National tion and aeronautical information which includes Airport. visual and radio aids to navigation, airports, (See ICAO term AERONAUTICAL CHART.) controlled airspace, permanent SUA, obstructions, and related data. AERONAUTICAL CHART [ICAO]− A representation of a portion of the earth, its culture and relief, c. En Route Low Altitude Charts− Provide specifically designated to meet the requirements of aeronautical information for en route instrument air navigation. navigation (IFR) in the low altitude stratum. Information includes the portrayal of airways, limits AERONAUTICAL INFORMATION MANUAL of controlled airspace, position identification and (AIM)− A primary FAA publication whose purpose frequencies of radio aids, selected airports, minimum is to instruct airmen about operating in the National en route and minimum obstruction clearance Airspace System of the U.S. It provides basic flight altitudes, airway distances, reporting points, perma- information, ATC Procedures and general instruc- nent SUA, and related data. Area charts, which are a tional information concerning health, medical facts, part of this series, furnish terminal data at a larger factors affecting flight safety, accident and hazard scale in congested areas. reporting, and types of aeronautical charts and their use. d. En Route High Altitude Charts− Provide AERONAUTICAL INFORMATION PUBLICA- aeronautical information for en route instrument TION (AIP) [ICAO]− A publication issued by or with navigation (IFR) in the high altitude stratum. the authority of a State and containing aeronautical Information includes the portrayal of jet routes, information of a lasting character essential to air identification and frequencies of radio aids, selected airports, distances, time zones, special use airspace, navigation. and related information. (See CHART SUPPLEMENT U.S.) AERONAUTICAL INFORMATION SERVICES e. Instrument Approach Procedure (IAP) Charts− (AIS)− A facility in Silver Spring, MD, established Portray the aeronautical data which is required to by FAA to operate a central aeronautical information execute an instrument approach to an airport. These service for the collection, validation, and dissemina- charts depict the procedures, including all related tion of aeronautical data in support of the activities of data, and the airport diagram. Each procedure is government, industry, and the aviation community. designated for use with a specific type of electronic The information is published in the National Flight navigation system including NDB, TACAN, VOR, Data Digest. ILS RNAV and GLS. These charts are identified by (See NATIONAL FLIGHT DATA DIGEST.) the type of navigational aid(s)/equipment required to provide final approach guidance. AFFIRMATIVE− Yes.

PCG A−3 Pilot/Controller Glossary 6/17/21

AFIS− AIR ROUTE SURVEILLANCE RADAR− Air route (See AUTOMATIC FLIGHT INFORMATION traffic control center (ARTCC) radar used primarily SERVICE − ALASKA FSSs ONLY.) to detect and display an aircraft’s position while en route between terminal areas. The ARSR enables AFP− controllers to provide radar air traffic control service (See AIRSPACE FLOW PROGRAM.) when aircraft are within the ARSR coverage. In some AHA− instances, ARSR may enable an ARTCC to provide (See AIRCRAFT HAZARD AREA.) terminal radar services similar to but usually more limited than those provided by a radar approach AIM− control. (See AERONAUTICAL INFORMATION AIR ROUTE TRAFFIC CONTROL CENTER MANUAL.) (ARTCC)− A facility established to provide air traffic AIP [ICAO]− control service to aircraft operating on IFR flight (See ICAO term AERONAUTICAL plans within controlled airspace and principally INFORMATION PUBLICATION.) during the en route phase of flight. When equipment capabilities and controller workload permit, certain AIR CARRIER DISTRICT OFFICE− An FAA field advisory/assistance services may be provided to VFR office serving an assigned geographical area, staffed aircraft. with Flight Standards personnel serving the aviation (See EN ROUTE AIR TRAFFIC CONTROL industry and the general public on matters related to SERVICES.) the certification and operation of scheduled air (Refer to AIM.) carriers and other large aircraft operations. AIR TAXI− Used to describe a helicopter/VTOL AIR DEFENSE EMERGENCY− A military emer- aircraft movement conducted above the surface but gency condition declared by a designated authority. normally not above 100 feet AGL. The aircraft may This condition exists when an attack upon the proceed either via hover taxi or flight at speeds more continental U.S., Alaska, Canada, or U.S. installa- than 20 knots. The pilot is solely responsible for tions in Greenland by hostile aircraft or missiles is selecting a safe airspeed/altitude for the operation considered probable, is imminent, or is taking place. being conducted. (Refer to AIM.) (See HOVER TAXI.) AIR DEFENSE IDENTIFICATION ZONE (ADIZ)− (Refer to AIM.) An area of airspace over land or water in which the AIR TRAFFIC− Aircraft operating in the air or on an ready identification, location, and control of all airport surface, exclusive of loading ramps and aircraft (except for Department of Defense and law parking areas. enforcement aircraft) is required in the interest of (See ICAO term AIR TRAFFIC.) national security. AIR TRAFFIC [ICAO]− All aircraft in flight or Note: ADIZ locations and operating and flight plan operating on the maneuvering area of an aerodrome. requirements for civil aircraft operations are specified in 14 CFR Part 99. AIR TRAFFIC CLEARANCE− An authorization by (Refer to AIM.) air traffic control for the purpose of preventing collision between known aircraft, for an aircraft to AIR NAVIGATION FACILITY− Any facility used proceed under specified traffic conditions within in, available for use in, or designed for use in, aid of controlled airspace. The pilot-in-command of an air navigation, including landing areas, lights, any aircraft may not deviate from the provisions of a apparatus or equipment for disseminating weather visual flight rules (VFR) or instrument flight rules information, for signaling, for radio-directional (IFR) air traffic clearance except in an emergency or finding, or for radio or other electrical communica- unless an amended clearance has been obtained. tion, and any other structure or mechanism having a Additionally, the pilot may request a different similar purpose for guiding or controlling flight in the clearance from that which has been issued by air air or the landing and takeoff of aircraft. traffic control (ATC) if information available to the (See NAVIGATIONAL AID.) pilot makes another course of action more practicable

PCG A−4 6/17/21 Pilot/Controller Glossary

or if aircraft equipment limitations or company AIR TRAFFIC CONTROL SPECIALIST− A person procedures forbid compliance with the clearance authorized to provide air traffic control service. issued. Pilots may also request clarification or (See AIR TRAFFIC CONTROL.) amendment, as appropriate, any time a clearance is (See FLIGHT SERVICE STATION.) not fully understood, or considered unacceptable (See ICAO term CONTROLLER.) because of safety of flight. Controllers should, in AIR TRAFFIC CONTROL SYSTEM COMMAND such instances and to the extent of operational CENTER (ATCSCC)− An Air Traffic Tactical practicality and safety, honor the pilot’s request. Operations facility responsible for monitoring and 14 CFR Part 91.3(a) states: “The pilot in command managing the flow of air traffic throughout the NAS, of an aircraft is directly responsible for, and is the producing a safe, orderly, and expeditious flow of final authority as to, the operation of that aircraft.” traffic while minimizing delays. The following THE PILOT IS RESPONSIBLE TO REQUEST AN functions are located at the ATCSCC: AMENDED CLEARANCE if ATC issues a a. Central Altitude Reservation Function clearance that would cause a pilot to deviate from a (CARF). Responsible for coordinating, planning, rule or regulation, or in the pilot’s opinion, would and approving special user requirements under the place the aircraft in jeopardy. Altitude Reservation (ALTRV) concept. (See ATC INSTRUCTIONS.) (See ALTITUDE RESERVATION.) (See ICAO term AIR TRAFFIC CONTROL b. Airport Reservation Office (ARO). Monitors CLEARANCE.) the operation and allocation of reservations for unscheduled operations at airports designated by the AIR TRAFFIC CONTROL− A service operated by Administrator as High Density Airports. These appropriate authority to promote the safe, orderly and airports are generally known as slot controlled expeditious flow of air traffic. airports. The ARO allocates reservations on a first (See ICAO term AIR TRAFFIC CONTROL come, first served basis determined by the time the SERVICE.) request is received at the ARO. (Refer to 14 CFR Part 93.) AIR TRAFFIC CONTROL CLEARANCE [ICAO]− (See CHART SUPPLEMENT U.S.) Authorization for an aircraft to proceed under c. U.S. Notice to Airmen (NOTAM) Office. conditions specified by an air traffic control unit. Responsible for collecting, maintaining, and distrib- Note 1: For convenience, the term air traffic control uting NOTAMs for the U.S. civilian and military, as clearance is frequently abbreviated to clearance well as international aviation communities. when used in appropriate contexts. (See NOTICE TO AIRMEN.) Note 2: The abbreviated term clearance may be d. Weather Unit. Monitor all aspects of weather prefixed by the words taxi, takeoff, departure, en for the U.S. that might affect aviation including cloud route, approach or landing to indicate the particular cover, visibility, winds, precipitation, thunderstorms, portion of flight to which the air traffic control clear- icing, turbulence, and more. Provide forecasts based ance relates. on observations and on discussions with meteorologists from various National Weather Service offices, AIR TRAFFIC CONTROL SERVICE− FAA facilities, airlines, and private weather services. (See AIR TRAFFIC CONTROL.) AIR TRAFFIC SERVICE− A generic term meaning: AIR TRAFFIC CONTROL SERVICE [ICAO]− A a. Flight Information Service. service provided for the purpose of: b. Alerting Service. c. Air Traffic Advisory Service. a. Preventing collisions: d. Air Traffic Control Service: 1. Between aircraft; and 1. Area Control Service, 2. On the maneuvering area between aircraft 2. Approach Control Service, or and obstructions. 3. Airport Control Service. b. Expediting and maintaining an orderly flow of AIR TRAFFIC SERVICE (ATS) ROUTES − The air traffic. term “ATS Route” is a generic term that includes

PCG A−5 Pilot/Controller Glossary 6/17/21

“VOR Federal airways,” “colored Federal airways,” operating at this weight during a particular phase of “jet routes,” and “RNAV routes.” The term “ATS flight. route” does not replace these more familiar route c. Large− Aircraft of more than 41,000 pounds, names, but serves only as an overall title when listing maximum certificated takeoff weight, up to but not the types of routes that comprise the United States including 300,000 pounds. route structure. d. Small− Aircraft of 41,000 pounds or less AIRBORNE− An aircraft is considered airborne maximum certificated takeoff weight. when all parts of the aircraft are off the ground. (Refer to AIM.) AIRBORNE DELAY− Amount of delay to be AIRCRAFT CONFLICT− Predicted conflict, within encountered in airborne holding. EDST of two aircraft, or between aircraft and AIRCRAFT− Device(s) that are used or intended to airspace. A Red alert is used for conflicts when the be used for flight in the air, and when used in air traffic predicted minimum separation is 5 nautical miles or control terminology, may include the flight crew. less. A Yellow alert is used when the predicted (See ICAO term AIRCRAFT.) minimum separation is between 5 and approximately 12 nautical miles. A Blue alert is used for conflicts

AIRCRAFT [ICAO]− Any machine that can derive between an aircraft and predefined airspace. support in the atmosphere from the reactions of the air other than the reactions of the air against the earth’s (See EN ROUTE DECISION SUPPORT surface. TOOL.) AIRCRAFT APPROACH CATEGORY− A AIRCRAFT LIST (ACL)− A view available with grouping of aircraft based on a speed of 1.3 times the EDST that lists aircraft currently in or predicted to be stall speed in the landing configuration at maximum in a particular sector’s airspace. The view contains gross landing weight. An aircraft must fit in only one textual flight data information in line format and may category. If it is necessary to maneuver at speeds in be sorted into various orders based on the specific excess of the upper limit of a speed range for a needs of the sector team. category, the minimums for the category for that (See EN ROUTE DECISION SUPPORT speed must be used. For example, an aircraft which TOOL.) falls in Category A, but is circling to land at a speed in excess of 91 knots, must use the approach AIRCRAFT SURGE LAUNCH AND Category B minimums when circling to land. The RECOVERY− Procedures used at USAF bases to categories are as follows: provide increased launch and recovery rates in instrument flight rules conditions. ASLAR is based a. Category A− Speed less than 91 knots. on: b. Category B− Speed 91 knots or more but less a. Reduced separation between aircraft which is than 121 knots. based on time or distance. Standard arrival separation c. Category C− Speed 121 knots or more but less applies between participants including multiple than 141 knots. flights until the DRAG point. The DRAG point is a d. Category D− Speed 141 knots or more but less published location on an ASLAR approach where than 166 knots. aircraft landing second in a formation slows to a e. Category E− Speed 166 knots or more. predetermined airspeed. The DRAG point is the (Refer to 14 CFR Part 97.) reference point at which MARSA applies as expanding elements effect separation within a flight AIRCRAFT CLASSES− For the purposes of Wake or between subsequent participating flights. Turbulence Separation Minima, ATC classifies b. ASLAR procedures shall be covered in a Letter aircraft as Super, Heavy, Large, and Small as follows: of Agreement between the responsible USAF a. Super. The Airbus A-380-800 (A388) and the military ATC facility and the concerned Federal Antonov An-225 (A225) are classified as super. Aviation Administration facility. Initial Approach b. Heavy− Aircraft capable of takeoff weights of Fix spacing requirements are normally addressed as 300,000 pounds or more whether or not they are a minimum.

PCG A−6 6/17/21 Pilot/Controller Glossary

AIRCRAFT HAZARD AREA (AHA)− Used by AIRPORT ARRIVAL RATE (AAR)− A dynamic ATC to segregate air traffic from a launch vehicle, input parameter specifying the number of arriving reentry vehicle, amateur rocket, jettisoned stages, aircraft which an airport or airspace can accept from hardware, or falling debris generated by failures the ARTCC per hour. The AAR is used to calculate associated with any of these activities. An AHA is the desired interval between successive arrival designated via NOTAM as either a TFR or stationary aircraft. ALTRV. Unless otherwise specified, the vertical AIRPORT DEPARTURE RATE (ADR)− A dynamic limits of an AHA are from the surface to unlimited. parameter specifying the number of aircraft which (See CONTINGENCY HAZARD AREA.) can depart an airport and the airspace can accept per (See REFINED HAZARD AREA.) hour. (See TRANSITIONAL HAZARD AREA.) AIRPORT ELEVATION− The highest point of an AIRCRAFT WAKE TURBULENCE CATE- airport’s usable runways measured in feet from mean GORIES− For the purpose of Wake Turbulence sea level. Recategorization (RECAT) Separation Minima, ATC (See TOUCHDOWN ZONE ELEVATION.) groups aircraft into categories ranging from Category (See ICAO term AERODROME ELEVATION.) A through Category I, dependent upon the version of AIRPORT LIGHTING− Various lighting aids that RECAT that is applied. Specific category assign- may be installed on an airport. Types of airport ments vary and are listed in the RECAT Orders. lighting include: AIRMEN’S METEOROLOGICAL INFORMA- a. Approach Light System (ALS)− An airport TION (AIRMET)− In-flight weather advisories lighting facility which provides visual guidance to issued only to amend the Aviation Surface Forecast, landing aircraft by radiating light beams in a Aviation Cloud Forecast, or area forecast concerning directional pattern by which the pilot aligns the weather phenomena which are of operational interest aircraft with the extended centerline of the runway on to all aircraft and potentially hazardous to aircraft his/her final approach for landing. Condenser- having limited capability because of lack of Discharge Sequential Flashing Lights/Sequenced equipment, instrumentation, or pilot qualifications. Flashing Lights may be installed in conjunction with AIRMETs concern weather of less severity than that the ALS at some airports. Types of Approach Light covered by SIGMETs or Convective SIGMETs. Systems are: AIRMETs cover moderate icing, moderate turbu- 1. ALSF-1− Approach Light System with lence, sustained winds of 30 knots or more at the Sequenced Flashing Lights in ILS Cat-I configura- surface, widespread areas of ceilings less than 1,000 tion. feet and/or visibility less than 3 miles, and extensive mountain obscurement. 2. ALSF-2− Approach Light System with Sequenced Flashing Lights in ILS Cat-II configura- (See AWW.) tion. The ALSF-2 may operate as an SSALR when (See CONVECTIVE SIGMET.) weather conditions permit. (See CWA.) 3. SSALF− Simplified Short Approach Light (See SIGMET.) System with Sequenced Flashing Lights. (Refer to AIM.) 4. SSALR− Simplified Short Approach Light AIRPORT− An area on land or water that is used or System with Runway Alignment Indicator Lights. intended to be used for the landing and takeoff of 5. MALSF− Medium Intensity Approach Light aircraft and includes its buildings and facilities, if System with Sequenced Flashing Lights. any. 6. MALSR− Medium Intensity Approach Light AIRPORT ADVISORY AREA− The area within ten System with Runway Alignment Indicator Lights. miles of an airport without a control tower or where 7. RLLS− Runway Lead-in Light System the tower is not in operation, and on which a Flight Consists of one or more series of flashing lights Service Station is located. installed at or near ground level that provides positive (See LOCAL AIRPORT ADVISORY.) visual guidance along an approach path, either (Refer to AIM.) curving or straight, where special problems exist with

PCG A−7 Pilot/Controller Glossary 6/17/21

hazardous terrain, obstructions, or noise abatement aircraft have three-bar VASIs which provide two procedures. visual glide paths to the same runway. 8. RAIL− Runway Alignment Indicator Lights− h. Precision Approach Path Indicator (PAPI)− An Sequenced Flashing Lights which are installed only airport lighting facility, similar to VASI, providing in combination with other light systems. vertical approach slope guidance to aircraft during 9. ODALS− Omnidirectional Approach Light- approach to landing. PAPIs consist of a single row of ing System consists of seven omnidirectional either two or four lights, normally installed on the left flashing lights located in the approach area of a side of the runway, and have an effective visual range nonprecision runway. Five lights are located on the of about 5 miles during the day and up to 20 miles at runway centerline extended with the first light night. PAPIs radiate a directional pattern of high located 300 feet from the threshold and extending at intensity red and white focused light beams which equal intervals up to 1,500 feet from the threshold. indicate that the pilot is “on path” if the pilot sees an The other two lights are located, one on each side of equal number of white lights and red lights, with the runway threshold, at a lateral distance of 40 feet white to the left of the red; “above path” if the pilot from the runway edge, or 75 feet from the runway sees more white than red lights; and “below path” if edge when installed on a runway equipped with a the pilot sees more red than white lights. VASI. i. Boundary Lights− Lights defining the perimeter (Refer to FAA Order JO 6850.2, VISUAL of an airport or landing area. GUIDANCE LIGHTING SYSTEMS.) (Refer to AIM.) b. Runway Lights/Runway Edge Lights− Lights AIRPORT MARKING AIDS− Markings used on having a prescribed angle of emission used to define runway and taxiway surfaces to identify a specific the lateral limits of a runway. Runway lights are runway, a runway threshold, a centerline, a hold line, uniformly spaced at intervals of approximately 200 etc. A runway should be marked in accordance with feet, and the intensity may be controlled or preset. its present usage such as: c. Touchdown Zone Lighting− Two rows of a. Visual. transverse light bars located symmetrically about the runway centerline normally at 100 foot intervals. The b. Nonprecision instrument. basic system extends 3,000 feet along the runway. c. Precision instrument. d. Runway Centerline Lighting− Flush centerline (Refer to AIM.) lights spaced at 50-foot intervals beginning 75 feet AIRPORT REFERENCE POINT (ARP)− The from the landing threshold and extending to within 75 approximate geometric center of all usable runway feet of the opposite end of the runway. surfaces. e. Threshold Lights− Fixed green lights arranged symmetrically left and right of the runway centerline, AIRPORT RESERVATION OFFICE− Office identifying the runway threshold. responsible for monitoring the operation of slot controlled airports. It receives and processes requests f. Runway End Identifier Lights (REIL)− Two for unscheduled operations at slot controlled airports. synchronized flashing lights, one on each side of the runway threshold, which provide rapid and positive AIRPORT ROTATING BEACON− A visual identification of the approach end of a particular NAVAID operated at many airports. At civil airports, runway. alternating white and green flashes indicate the g. Visual Approach Slope Indicator (VASI)− An location of the airport. At military airports, the airport lighting facility providing vertical visual beacons flash alternately white and green, but are approach slope guidance to aircraft during approach differentiated from civil beacons by dualpeaked (two to landing by radiating a directional pattern of high quick) white flashes between the green flashes. intensity red and white focused light beams which (See INSTRUMENT FLIGHT RULES.) indicate to the pilot that he/she is “on path” if he/she (See SPECIAL VFR OPERATIONS.) sees red/white, “above path” if white/white, and (See ICAO term AERODROME BEACON.) “below path” if red/red. Some airports serving large (Refer to AIM.)

PCG A−8 6/17/21 Pilot/Controller Glossary

AIRPORT STREAM FILTER (ASF)− An on/off implemented in various forms depending upon the filter that allows the conflict notification function to needs of the air traffic system. be inhibited for arrival streams into single or multiple AIRSPACE HIERARCHY− Within the airspace airports to prevent nuisance alerts. classes, there is a hierarchy and, in the event of an AIRPORT SURFACE DETECTION EQUIPMENT overlap of airspace: Class A preempts Class B, Class (ASDE)− Surveillance equipment specifically de- B preempts Class C, Class C preempts Class D, Class signed to detect aircraft, vehicular traffic, and other D preempts Class E, and Class E preempts Class G. objects, on the surface of an airport, and to present the AIRSPEED− The speed of an aircraft relative to its image on a tower display. Used to augment visual surrounding air mass. The unqualified term observation by tower personnel of aircraft and/or “airspeed” means one of the following: vehicular movements on runways and taxiways. a. Indicated Airspeed− The speed shown on the There are three ASDE systems deployed in the NAS: aircraft airspeed indicator. This is the speed used in a. ASDE−3− a Surface Movement Radar. pilot/controller communications under the general b. ASDE−X− a system that uses an X−band term “airspeed.” Surface Movement Radar, multilateration, and (Refer to 14 CFR Part 1.) ADS−B. b. True Airspeed− The airspeed of an aircraft c. Airport Surface Surveillance Capability relative to undisturbed air. Used primarily in flight (ASSC)− A system that uses Surface Movement planning and en route portion of flight. When used in Radar, multilateration, and ADS−B. pilot/controller communications, it is referred to as “true airspeed” and not shortened to “airspeed.” AIRPORT SURVEILLANCE RADAR− Approach AIRSTART− The starting of an aircraft engine while control radar used to detect and display an aircraft’s the aircraft is airborne, preceded by engine shutdown position in the terminal area. ASR provides range and during training flights or by actual engine failure. azimuth information but does not provide elevation data. Coverage of the ASR can extend up to 60 miles. AIRWAY− A Class E airspace area established in the form of a corridor, the centerline of which is defined AIRPORT TAXI CHARTS− by radio navigational aids. (See AERONAUTICAL CHART.) (See FEDERAL AIRWAYS.) AIRPORT TRAFFIC CONTROL SERVICE− A (See ICAO term AIRWAY.) service provided by a control tower for aircraft (Refer to 14 CFR Part 71.) operating on the movement area and in the vicinity of (Refer to AIM.) an airport. AIRWAY [ICAO]− A control area or portion thereof (See MOVEMENT AREA.) established in the form of corridor equipped with (See TOWER.) radio navigational aids. (See ICAO term AERODROME CONTROL AIRWAY BEACON− Used to mark airway segments SERVICE.) in remote mountain areas. The light flashes Morse AIRPORT TRAFFIC CONTROL TOWER− Code to identify the beacon site. (See TOWER.) (Refer to AIM.) AIRSPACE CONFLICT− Predicted conflict of an AIS− aircraft and active Special Activity Airspace (SAA). (See AERONAUTICAL INFORMATION SERVICES.) AIRSPACE FLOW PROGRAM (AFP)− AFP is a AIT− Traffic Management (TM) process administered by (See AUTOMATED INFORMATION the Air Traffic Control System Command Center TRANSFER.) (ATCSCC) where aircraft are assigned an Expect Departure Clearance Time (EDCT) in order to ALERFA (Alert Phase) [ICAO]− A situation wherein manage capacity and demand for a specific area of the apprehension exists as to the safety of an aircraft and National Airspace System (NAS). The purpose of the its occupants. program is to mitigate the effects of en route ALERT− A notification to a position that there constraints. It is a flexible program and may be is an aircraft-to-aircraft or aircraft-to-airspace

PCG A−9 Pilot/Controller Glossary 6/17/21 conflict, as detected by Automated Problem ALTITUDE− The height of a level, point, or object Detection (APD). measured in feet Above Ground Level (AGL) or from Mean Sea Level (MSL). ALERT AREA− (See FLIGHT LEVEL.) (See SPECIAL USE AIRSPACE.) a. MSL Altitude− Altitude expressed in feet measured from mean sea level. ALERT NOTICE (ALNOT)− A request originated by a flight service station (FSS) or an air route traffic b. AGL Altitude− Altitude expressed in feet control center (ARTCC) for an extensive commu- measured above ground level. nication search for overdue, unreported, or missing c. Indicated Altitude− The altitude as shown by an aircraft. altimeter. On a pressure or barometric altimeter it is altitude as shown uncorrected for instrument error ALERTING SERVICE− A service provided to notify and uncompensated for variation from standard appropriate organizations regarding aircraft in need atmospheric conditions. of search and rescue aid and assist such organizations (See ICAO term ALTITUDE.) as required. ALTITUDE [ICAO]− The vertical distance of a level, ALNOT− a point or an object considered as a point, measured (See ALERT NOTICE.) from mean sea level (MSL). ALTITUDE READOUT− An aircraft’s altitude, ALONG−TRACK DISTANCE (ATD)− The hori- transmitted via the Mode C transponder feature, that zontal distance between the aircraft’s current position is visually displayed in 100-foot increments on a and a fix measured by an area navigation system that radar scope having readout capability. is not subject to slant range errors. (See ALPHANUMERIC DISPLAY.) ALPHANUMERIC DISPLAY− Letters and numer- (See AUTOMATED RADAR TERMINAL als used to show identification, altitude, beacon code, SYSTEMS.) and other information concerning a target on a radar (Refer to AIM.) display. ALTITUDE RESERVATION (ALTRV)− Airspace (See AUTOMATED RADAR TERMINAL utilization under prescribed conditions normally SYSTEMS.) employed for the mass movement of aircraft or other special user requirements which cannot otherwise be ALTERNATE AERODROME [ICAO]− An aero- accomplished. ALTRVs are approved by the drome to which an aircraft may proceed when it appropriate FAA facility. becomes either impossible or inadvisable to proceed (See AIR TRAFFIC CONTROL SYSTEM to or to land at the aerodrome of intended landing. COMMAND CENTER.) Note: The aerodrome from which a flight departs may also be an en-route or a destination alternate ALTITUDE RESTRICTION− An altitude or alti- aerodrome for the flight. tudes, stated in the order flown, which are to be maintained until reaching a specific point or time. Altitude restrictions may be issued by ATC due to ALTERNATE AIRPORT− An airport at which an traffic, terrain, or other airspace considerations. aircraft may land if a landing at the intended airport becomes inadvisable. ALTITUDE RESTRICTIONS ARE CANCELED− (See ICAO term ALTERNATE AERODROME.) Adherence to previously imposed altitude restrictions is no longer required during a climb or descent. ALTIMETER SETTING− The barometric pressure reading used to adjust a pressure altimeter for ALTRV− variations in existing atmospheric pressure or to the (See ALTITUDE RESERVATION.) standard altimeter setting (29.92). AMVER− (Refer to 14 CFR Part 91.) (See AUTOMATED MUTUAL-ASSISTANCE (Refer to AIM.) VESSEL RESCUE SYSTEM.)

PCG A−10 6/17/21 Pilot/Controller Glossary

APB− departing aircraft. These locations are identified by (See AUTOMATED PROBLEM DETECTION signs and markings. BOUNDARY.) APPROACH LIGHT SYSTEM− APD− (See AIRPORT LIGHTING.) (See AUTOMATED PROBLEM DETECTION.) APPROACH SEQUENCE− The order in which aircraft are positioned while on approach or awaiting

APDIA− approach clearance. (See AUTOMATED PROBLEM DETECTION (See LANDING SEQUENCE.) INHIBITED AREA.) (See ICAO term APPROACH SEQUENCE.) APPROACH CLEARANCE− Authorization by APPROACH SEQUENCE [ICAO]− The order in ATC for a pilot to conduct an instrument approach. which two or more aircraft are cleared to approach to The type of instrument approach for which a land at the aerodrome. clearance and other pertinent information is provided APPROACH SPEED− The recommended speed in the approach clearance when required. contained in aircraft manuals used by pilots when (See CLEARED APPROACH.) making an approach to landing. This speed will vary (See INSTRUMENT APPROACH for different segments of an approach as well as for PROCEDURE.) aircraft weight and configuration. (Refer to AIM.) (Refer to 14 CFR Part 91.) APPROACH WITH VERTICAL GUIDANCE (APV)– A term used to describe RNAV approach APPROACH CONTROL FACILITY− A terminal procedures that provide lateral and vertical guidance ATC facility that provides approach control service in but do not meet the requirements to be considered a a terminal area. precision approach. (See APPROACH CONTROL SERVICE.) APPROPRIATE ATS AUTHORITY [ICAO]− The (See RADAR APPROACH CONTROL relevant authority designated by the State responsible FACILITY.) for providing air traffic services in the airspace APPROACH CONTROL SERVICE− Air traffic concerned. In the United States, the “appropriate ATS control service provided by an approach control authority” is the Program Director for Air Traffic facility for arriving and departing VFR/IFR aircraft Planning and Procedures, ATP-1. and, on occasion, en route aircraft. At some airports APPROPRIATE AUTHORITY− not served by an approach control facility, the a. Regarding flight over the high seas: the relevant ARTCC provides limited approach control service. authority is the State of Registry. (See ICAO term APPROACH CONTROL b. Regarding flight over other than the high seas: SERVICE.) the relevant authority is the State having sovereignty (Refer to AIM.) over the territory being overflown. APPROACH CONTROL SERVICE [ICAO]− Air APPROPRIATE OBSTACLE CLEARANCE traffic control service for arriving or departing MINIMUM ALTITUDE− Any of the following: controlled flights. (See MINIMUM EN ROUTE IFR ALTITUDE.) (See MINIMUM IFR ALTITUDE.) APPROACH GATE− An imaginary point used (See MINIMUM OBSTRUCTION CLEARANCE within ATC as a basis for vectoring aircraft to the ALTITUDE.) final approach course. The gate will be established (See MINIMUM VECTORING ALTITUDE.) along the final approach course 1 mile from the final approach fix on the side away from the airport and APPROPRIATE TERRAIN CLEARANCE will be no closer than 5 miles from the landing MINIMUM ALTITUDE− Any of the following: threshold. (See MINIMUM EN ROUTE IFR ALTITUDE.) (See MINIMUM IFR ALTITUDE.) APPROACH/DEPARTURE HOLD AREA− The (See MINIMUM OBSTRUCTION CLEARANCE locations on taxiways in the approach or departure ALTITUDE.) areas of a runway designated to protect landing or (See MINIMUM VECTORING ALTITUDE.)

PCG A−11 Pilot/Controller Glossary 6/17/21

APRON− A defined area on an airport or heliport Course reversal or radar vectoring may be required at intended to accommodate aircraft for purposes of busy terminals with multiple runways. loading or unloading passengers or cargo, refueling, d. TERMINAL ARRIVAL AREA (TAA)− The parking, or maintenance. With regard to seaplanes, a TAA is controlled airspace established in conjunction ramp is used for access to the apron from the water. with the Standard or Modified T and I RNAV (See ICAO term APRON.) approach configurations. In the standard TAA, there are three areas: straight-in, left base, and right base. APRON [ICAO]− A defined area, on a land The arc boundaries of the three areas of the TAA are aerodrome, intended to accommodate aircraft for published portions of the approach and allow aircraft purposes of loading or unloading passengers, mail or to transition from the en route structure direct to the cargo, refueling, parking or maintenance. nearest IAF. TAAs will also eliminate or reduce ARC− The track over the ground of an aircraft flying feeder routes, departure extensions, and procedure at a constant distance from a navigational aid by turns or course reversal. reference to distance measuring equipment (DME). 1. STRAIGHT-IN AREA− A 30 NM arc centered on the IF bounded by a straight line AREA CONTROL CENTER [ICAO]− An air traffic extending through the IF perpendicular to the control facility primarily responsible for ATC intermediate course. services being provided IFR aircraft during the en route phase of flight. The U.S. equivalent facility is 2. LEFT BASE AREA− A 30 NM arc centered an air route traffic control center (ARTCC). on the right corner IAF. The area shares a boundary with the straight-in area except that it extends out for AREA NAVIGATION (RNAV)− A method of 30 NM from the IAF and is bounded on the other side navigation which permits aircraft operation on any by a line extending from the IF through the FAF to the desired flight path within the coverage of ground− or arc. space−based navigation aids or within the limits of 3. RIGHT BASE AREA− A 30 NM arc the capability of self-contained aids, or a combination centered on the left corner IAF. The area shares a of these. boundary with the straight-in area except that it Note: Area navigation includes performance− extends out for 30 NM from the IAF and is bounded based navigation as well as other operations that on the other side by a line extending from the IF do not meet the definition of performance−based through the FAF to the arc. navigation. AREA NAVIGATION (RNAV) GLOBAL AREA NAVIGATION (RNAV) APPROACH POSITIONING SYSTEM (GPS) PRECISION CONFIGURATION: RUNWAY MONITORING (PRM) APPROACH– A GPS approach, which requires vertical guidance, a. STANDARD T− An RNAV approach whose used in lieu of another type of PRM approach to design allows direct flight to any one of three initial conduct approaches to parallel runways whose approach fixes (IAF) and eliminates the need for extended centerlines are separated by less than 4,300 procedure turns. The standard design is to align the feet and at least 3,000 feet, where simultaneous close procedure on the extended centerline with the missed parallel approaches are permitted. Also used in lieu approach point (MAP) at the runway threshold, the of an ILS PRM and/or LDA PRM approach to final approach fix (FAF), and the initial approach/ conduct Simultaneous Offset Instrument Approach intermediate fix (IAF/IF). The other two IAFs will be (SOIA) operations. established perpendicular to the IF. b. MODIFIED T− An RNAV approach design for ARMY AVIATION FLIGHT INFORMATION single or multiple runways where terrain or BULLETIN− A bulletin that provides air operation operational constraints do not allow for the standard data covering Army, National Guard, and Army T. The “T” may be modified by increasing or Reserve aviation activities. decreasing the angle from the corner IAF(s) to the IF ARO− or by eliminating one or both corner IAFs. (See AIRPORT RESERVATION OFFICE.) c. STANDARD I− An RNAV approach design for ARRESTING SYSTEM− A safety device consisting a single runway with both corner IAFs eliminated. of two major components, namely, engaging or

PCG A−12 6/17/21 Pilot/Controller Glossary

catching devices and energy absorption devices for ASF− the purpose of arresting both tailhook and/or (See AIRPORT STREAM FILTER.) nontailhook-equipped aircraft. It is used to prevent ASLAR− aircraft from overrunning runways when the aircraft (See AIRCRAFT SURGE LAUNCH AND cannot be stopped after landing or during aborted RECOVERY.) takeoff. Arresting systems have various names; e.g., arresting gear, hook device, wire barrier cable. ASP− (See ABORT.) (See ARRIVAL SEQUENCING PROGRAM.) (Refer to AIM.) ASR− ARRIVAL AIRCRAFT INTERVAL− An internally (See AIRPORT SURVEILLANCE RADAR.) generated program in hundredths of minutes based ASR APPROACH− upon the AAR. AAI is the desired optimum interval (See SURVEILLANCE APPROACH.) between successive arrival aircraft over the vertex. ASSOCIATED− A radar target displaying a data ARRIVAL CENTER− The ARTCC having jurisdic- block with flight identification and altitude tion for the impacted airport. information. (See UNASSOCIATED.) ARRIVAL DELAY− A parameter which specifies a period of time in which no aircraft will be metered for ATC− arrival at the specified airport. (See AIR TRAFFIC CONTROL.) ATC ADVISES− Used to prefix a message of ARRIVAL SECTOR− An operational control sector noncontrol information when it is relayed to an containing one or more meter fixes. aircraft by other than an air traffic controller. ARRIVAL SECTOR ADVISORY LIST− An (See ADVISORY.) ordered list of data on arrivals displayed at the ATC ASSIGNED AIRSPACE− Airspace of defined PVD/MDM of the sector which controls the meter vertical/lateral limits, assigned by ATC, for the fix. purpose of providing air traffic segregation between ARRIVAL SEQUENCING PROGRAM− The auto- the specified activities being conducted within the mated program designed to assist in sequencing assigned airspace and other IFR air traffic. aircraft destined for the same airport. (See SPECIAL USE AIRSPACE.) ATC CLEARANCE− ARRIVAL TIME− The time an aircraft touches down (See AIR TRAFFIC CLEARANCE.) on arrival. ATC CLEARS− Used to prefix an ATC clearance ARSR− when it is relayed to an aircraft by other than an air (See AIR ROUTE SURVEILLANCE RADAR.) traffic controller. ARTCC− ATC INSTRUCTIONS− Directives issued by air (See AIR ROUTE TRAFFIC CONTROL traffic control for the purpose of requiring a pilot to CENTER.) take specific actions; e.g., “Turn left heading two five zero,” “Go around,” “Clear the runway.” ASDA− (Refer to 14 CFR Part 91.) (See ACCELERATE-STOP DISTANCE AVAILABLE.) ATC PREFERRED ROUTE NOTIFICATION− EDST notification to the appropriate controller of the ASDA [ICAO]− need to determine if an ATC preferred route needs to (See ICAO Term ACCELERATE-STOP be applied, based on destination airport. DISTANCE AVAILABLE.) (See ROUTE ACTION NOTIFICATION.) ASDE− (See EN ROUTE DECISION SUPPORT TOOL.) (See AIRPORT SURFACE DETECTION ATC PREFERRED ROUTES− Preferred routes that EQUIPMENT.) are not automatically applied by Host.

PCG A−13 Pilot/Controller Glossary 6/17/21

ATC REQUESTS− Used to prefix an ATC request or any comparable ground−based system that enables when it is relayed to an aircraft by other than an air the identification of aircraft. traffic controller. Note: A comparable ground−based system is one that has been demonstrated, by comparative ATC SECURITY SERVICES− Communications assessment or other methodology, to have a level and security tracking provided by an ATC facility in of safety and performance equal to or better than support of the DHS, the DOD, or other Federal monopulse SSR. security elements in the interest of national security. ATCAA− Such security services are only applicable within (See ATC ASSIGNED AIRSPACE.) designated areas. ATC security services do not include ATC basic radar services or flight following. ATCRBS− (See RADAR.) ATC SECURITY SERVICES POSITION− The ATCSCC− position responsible for providing ATC security (See AIR TRAFFIC CONTROL SYSTEM services as defined. This position does not provide COMMAND CENTER.) ATC, IFR separation, or VFR flight following ATCT− services, but is responsible for providing security (See TOWER.) services in an area comprising airspace assigned to one or more ATC operating sectors. This position ATD− may be combined with control positions. (See ALONG−TRACK DISTANCE.) ATIS− ATC SECURITY TRACKING− The continuous (See AUTOMATIC TERMINAL INFORMATION tracking of aircraft movement by an ATC facility in SERVICE.) support of the DHS, the DOD, or other security ATIS [ICAO]− elements for national security using radar (i.e., radar (See ICAO Term AUTOMATIC TERMINAL tracking) or other means (e.g., manual tracking) INFORMATION SERVICE.) without providing basic radar services (including traffic advisories) or other ATC services not defined ATS ROUTE [ICAO]− A specified route designed for in this section. channeling the flow of traffic as necessary for the provision of air traffic services. ATS SURVEILLANCE SERVICE [ICAO]– A term Note: The term “ATS Route” is used to mean used to indicate a service provided directly by means variously, airway, advisory route, controlled or of an ATS surveillance system. uncontrolled route, arrival or departure, etc. ATTENTION ALL USERS PAGE (AAUP)- The ATC SURVEILLANCE SOURCE– Used by ATC AAUP provides the pilot with additional information for establishing identification, control and separation relative to conducting a specific operation, for using a target depicted on an air traffic control example, PRM approaches and RNAV departures. facility’s video display that has met the relevant safety standards for operational use and received AUTOLAND APPROACH−An autoland system from one, or a combination, of the following aids by providing control of aircraft systems during surveillance sources: a precision instrument approach to at least decision a. Radar (See RADAR.) altitude and possibly all the way to touchdown, as b. ADS-B (See AUTOMATIC DEPENDENT well as in some cases, through the landing rollout. SURVEILLANCE−BROADCAST.) The autoland system is a sub-system of the autopilot c. WAM (See WIDE AREA MULTILATERATION.) system from which control surface management occurs. The aircraft autopilot sends instructions to the (See INTERROGATOR.) autoland system and monitors the autoland system (See TRANSPONDER.) performance and integrity during its execution. (See ICAO term RADAR.) AUTOMATED EMERGENCY DESCENT− (Refer to AIM.) (See EMERGENCY DESCENT MODE.) ATS SURVEILLANCE SYSTEM [ICAO]– A AUTOMATED INFORMATION TRANSFER generic term meaning variously, ADS−B, PSR, SSR (AIT)− A precoordinated process, specifically

PCG A−14 6/17/21 Pilot/Controller Glossary

defined in facility directives, during which a transfer AUTOMATIC CARRIER LANDING SYSTEM− of altitude control and/or radar identification is U.S. Navy final approach equipment consisting of accomplished without verbal coordination between precision tracking radar coupled to a computer data controllers using information communicated in a full link to provide continuous information to the aircraft, data block. monitoring capability to the pilot, and a backup approach system. AUTOMATED MUTUAL-ASSISTANCE VESSEL RESCUE SYSTEM− A facility which can deliver, in AUTOMATIC DEPENDENT SURVEILLANCE a matter of minutes, a surface picture (SURPIC) of (ADS) [ICAO]− A surveillance technique in which vessels in the area of a potential or actual search and aircraft automatically provide, via a data link, data rescue incident, including their predicted positions derived from on−board navigation and position and their characteristics. fixing systems, including aircraft identification, four (See FAA Order JO 7110.65, Para 10−6−4, dimensional position and additional data as INFLIGHT CONTINGENCIES.) appropriate. AUTOMATED PROBLEM DETECTION (APD)− AUTOMATIC DEPENDENT SURVEILLANCE− An Automation Processing capability that compares BROADCAST (ADS-B)− A surveillance system in trajectories in order to predict conflicts. which an aircraft or vehicle to be detected is fitted with cooperative equipment in the form of a data link AUTOMATED PROBLEM DETECTION transmitter. The aircraft or vehicle periodically BOUNDARY (APB)− The adapted distance beyond broadcasts its GNSS−derived position and other a facilities boundary defining the airspace within required information such as identity and velocity, which EDST performs conflict detection. which is then received by a ground−based or (See EN ROUTE DECISION SUPPORT TOOL.) space−based receiver for processing and display at an air traffic control facility, as well as by suitably AUTOMATED PROBLEM DETECTION INHIB- equipped aircraft. ITED AREA (APDIA)− Airspace surrounding a (See AUTOMATIC DEPENDENT terminal area within which APD is inhibited for all SURVEILLANCE−BROADCAST IN.) flights within that airspace. (See AUTOMATIC DEPENDENT SURVEILLANCE−BROADCAST OUT.) AUTOMATED WEATHER SYSTEM− Any of the (See COOPERATIVE SURVEILLANCE.) automated weather sensor platforms that collect (See GLOBAL POSITIONING SYSTEM.) weather data at airports and disseminate the weather (See SPACE−BASED ADS−B.) information via radio and/or landline. The systems currently consist of the Automated Surface Observ- AUTOMATIC DEPENDENT SURVEILLANCE− ing System (ASOS) and Automated Weather BROADCAST IN (ADS−B In)− Aircraft avionics Observation System (AWOS). capable of receiving ADS−B Out transmissions directly from other aircraft, as well as traffic or AUTOMATED UNICOM− Provides completely weather information transmitted from ground automated weather, radio check capability and airport stations. advisory information on an Automated UNICOM (See AUTOMATIC DEPENDENT system. These systems offer a variety of features, SURVEILLANCE−BROADCAST OUT.) typically selectable by microphone clicks, on the (See AUTOMATIC DEPENDENT UNICOM frequency. Availability will be published SURVEILLANCE−REBROADCAST.) in the Chart Supplement U.S. and approach charts. (See FLIGHT INFORMATION SERVICE−BROADCAST.)

AUTOMATIC ALTITUDE REPORT− (See TRAFFIC INFORMATION (See ALTITUDE READOUT.) SERVICE−BROADCAST.) AUTOMATIC ALTITUDE REPORTING− That AUTOMATIC DEPENDENT SURVEILLANCE− function of a transponder which responds to Mode C BROADCAST OUT (ADS−B Out)− The transmitter interrogations by transmitting the aircraft’s altitude onboard an aircraft or ground vehicle that in 100-foot increments. periodically broadcasts its GNSS−derived position

PCG A−15 Pilot/Controller Glossary 6/17/21

along with other required information, such as discrete VHF radio frequency (usually the ASOS/ identity, altitude, and velocity. AWOS frequency). (See AUTOMATIC DEPENDENT AUTOMATIC TERMINAL INFORMATION SER- SURVEILLANCE−BROADCAST.) VICE− The continuous broadcast of recorded (See AUTOMATIC DEPENDENT noncontrol information in selected terminal areas. Its SURVEILLANCE−BROADCAST IN.) purpose is to improve controller effectiveness and to AUTOMATIC DEPENDENT SURVEILLANCE− relieve frequency congestion by automating the CONTRACT (ADS−C)− A data link position repetitive transmission of essential but routine reporting system, controlled by a ground station, that information; e.g., “Los Angeles information Alfa. establishes contracts with an aircraft’s avionics that One three zero zero Coordinated Universal Time. occur automatically whenever specific events occur, Weather, measured ceiling two thousand overcast, or specific time intervals are reached. visibility three, haze, smoke, temperature seven one, dew point five seven, wind two five zero at five, AUTOMATIC DEPENDENT SURVEILLANCE- altimeter two niner niner six. I-L-S Runway Two Five REBROADCAST (ADS-R)− A datalink translation Left approach in use, Runway Two Five Right closed, function of the ADS−B ground system required to advise you have Alfa.” accommodate the two separate operating frequencies (See ICAO term AUTOMATIC TERMINAL (978 MHz and 1090 MHz). The ADS−B system INFORMATION SERVICE.) receives the ADS−B messages transmitted on one (Refer to AIM.) frequency and ADS−R translates and reformats the AUTOMATIC TERMINAL INFORMATION SER- information for rebroadcast and use on the other VICE [ICAO]− The provision of current, routine frequency. This allows ADS−B In equipped aircraft information to arriving and departing aircraft by to see nearby ADS−B Out traffic regardless of the means of continuous and repetitive broadcasts operating link of the other aircraft. Aircraft operating throughout the day or a specified portion of the day. on the same ADS−B frequency exchange information directly and do not require the ADS−R translation AUTOROTATION− A rotorcraft flight condition in function. which the lifting rotor is driven entirely by action of the air when the rotorcraft is in motion. AUTOMATIC DIRECTION FINDER− An aircraft a. Autorotative Landing/Touchdown Autorota- radio navigation system which senses and indicates tion. Used by a pilot to indicate that the landing will the direction to a L/MF nondirectional radio beacon be made without applying power to the rotor. (NDB) ground transmitter. Direction is indicated to the pilot as a magnetic bearing or as a relative bearing b. Low Level Autorotation. Commences at an to the longitudinal axis of the aircraft depending on altitude well below the traffic pattern, usually below the type of indicator installed in the aircraft. In certain 100 feet AGL and is used primarily for tactical applications, such as military, ADF operations may military training. be based on airborne and ground transmitters in the c. 180 degrees Autorotation. Initiated from a VHF/UHF frequency spectrum. downwind heading and is commenced well inside the (See BEARING.) normal traffic pattern. “Go around” may not be (See NONDIRECTIONAL BEACON.) possible during the latter part of this maneuver. AVAILABLE LANDING DISTANCE (ALD)− The AUTOMATIC FLIGHT INFORMATION SER- portion of a runway available for landing and roll-out VICE (AFIS) − ALASKA FSSs ONLY− The for aircraft cleared for LAHSO. This distance is continuous broadcast of recorded non−control measured from the landing threshold to the information at airports in Alaska where a FSS hold-short point. provides local airport advisory service. The AFIS broadcast automates the repetitive transmission of AVIATION WEATHER SERVICE− A service essential but routine information such as weather, provided by the National Weather Service (NWS) and wind, altimeter, favored runway, braking action, FAA which collects and disseminates pertinent airport NOTAMs, and other applicable information. weather information for pilots, aircraft operators, and The information is continuously broadcast over a ATC. Available aviation weather reports and

PCG A−16 6/17/21 Pilot/Controller Glossary forecasts are displayed at each NWS office and FAA FSS. (See TRANSCRIBED WEATHER BROADCAST.) (See WEATHER ADVISORY.) (Refer to AIM.) AWW− (See SEVERE WEATHER FORECAST ALERTS.)

PCG A−17

6/17/21 Pilot/Controller Glossary B

BACK-TAXI− A term used by air traffic controllers BLIND VELOCITY [ICAO]− The radial velocity of to taxi an aircraft on the runway opposite to the traffic a moving target such that the target is not seen on flow. The aircraft may be instructed to back-taxi to primary radars fitted with certain forms of fixed echo the beginning of the runway or at some point before suppression. reaching the runway end for the purpose of departure BLIND ZONE− or to exit the runway. (See BLIND SPOT.) BASE LEG− BLOCKED− Phraseology used to indicate that a (See TRAFFIC PATTERN.) radio transmission has been distorted or interrupted due to multiple simultaneous radio transmissions. BEACON− (See AERONAUTICAL BEACON.) BOTTOM ALTITUDE– In reference to published altitude restrictions on a STAR or STAR runway (See AIRPORT ROTATING BEACON.) transition, the lowest altitude authorized. (See AIRWAY BEACON.) (See MARKER BEACON.) BOUNDARY LIGHTS− (See NONDIRECTIONAL BEACON.) (See AIRPORT LIGHTING.) (See RADAR.) BRAKING ACTION (GOOD, GOOD TO MEDI- UM, MEDIUM, MEDIUM TO POOR, POOR, OR BEARING− The horizontal direction to or from any NIL)− A report of conditions on the airport point, usually measured clockwise from true north, movement area providing a pilot with a degree/quali- magnetic north, or some other reference point ty of braking to expect. Braking action is reported in through 360 degrees. terms of good, good to medium, medium, medium to (See NONDIRECTIONAL BEACON.) poor, poor, or nil. BELOW MINIMUMS− Weather conditions below (See RUNWAY CONDITION READING.) the minimums prescribed by regulation for the (See RUNWAY CONDITION REPORT.) particular action involved; e.g., landing minimums, (See RUNWAY CONDITION CODES.) takeoff minimums. BRAKING ACTION ADVISORIES− When tower controllers receive runway braking action reports BLAST FENCE− A barrier that is used to divert or which include the terms “medium,” “poor,” or “nil,” dissipate jet or propeller blast. or whenever weather conditions are conducive to BLAST PAD− A surface adjacent to the ends of a deteriorating or rapidly changing runway braking runway provided to reduce the erosive effect of jet conditions, the tower will include on the ATIS blast and propeller wash. broadcast the statement, “Braking Action Advisories are in Effect.” During the time braking action BLIND SPEED− The rate of departure or closing of advisories are in effect, ATC will issue the most a target relative to the radar antenna at which current braking action report for the runway in use to cancellation of the primary radar target by moving each arriving and departing aircraft. Pilots should be target indicator (MTI) circuits in the radar equipment prepared for deteriorating braking conditions and causes a reduction or complete loss of signal. should request current runway condition information (See ICAO term BLIND VELOCITY.) if not issued by controllers. Pilots should also be prepared to provide a descriptive runway condition BLIND SPOT− An area from which radio report to controllers after landing. transmissions and/or radar echoes cannot be received. The term is also used to describe portions BREAKOUT− A technique to direct aircraft out of of the airport not visible from the control tower. the approach stream. In the context of simultaneous (independent) parallel operations, a breakout is used BLIND TRANSMISSION− to direct threatened aircraft away from a deviating (See TRANSMITTING IN THE BLIND.) aircraft.

PCG B−1 Pilot/Controller Glossary 6/17/21

BROADCAST− Transmission of information for BUFFER AREA− As applied to an MVA or MIA which an acknowledgement is not expected. chart, a depicted 3 NM or 5 NM radius MVA/MIA (See ICAO term BROADCAST.) sector isolating a displayed obstacle for which the BROADCAST [ICAO]− A transmission of informa- sector is established. A portion of a buffer area can tion relating to air navigation that is not addressed to also be inclusive of a MVA/MIA sector polygon a specific station or stations. boundary.

PCG B−2 6/17/21 Pilot/Controller Glossary C

CALCULATED LANDING TIME− A term that may CENTER’S AREA− The specified airspace within be used in place of tentative or actual calculated which an air route traffic control center (ARTCC) landing time, whichever applies. provides air traffic control and advisory service. (See AIR ROUTE TRAFFIC CONTROL CALL FOR RELEASE− Wherein the overlying CENTER.) ARTCC requires a terminal facility to initiate verbal (Refer to AIM.) coordination to secure ARTCC approval for release of a departure into the en route environment. CENTER TRACON AUTOMATION SYSTEM (CTAS)− A computerized set of programs designed CALL UP− Initial voice contact between a facility to aid Air Route Traffic Control Centers and and an aircraft, using the identification of the unit TRACONs in the management and control of air being called and the unit initiating the call. traffic. (Refer to AIM.) CENTER WEATHER ADVISORY− An unsched- CANADIAN MINIMUM NAVIGATION PERFOR- uled weather advisory issued by Center Weather MANCE SPECIFICATION AIRSPACE− That Service Unit meteorologists for ATC use to alert portion of Canadian domestic airspace within which pilots of existing or anticipated adverse weather MNPS separation may be applied. conditions within the next 2 hours. A CWA may CARDINAL ALTITUDES− “Odd” or “Even” modify or redefine a SIGMET. thousand-foot altitudes or flight levels; e.g., 5,000, (See AWW.) 6,000, 7,000, FL 250, FL 260, FL 270. (See AIRMET.) (See ALTITUDE.) (See CONVECTIVE SIGMET.) (See FLIGHT LEVEL.) (See SIGMET.) (Refer to AIM.) CARDINAL FLIGHT LEVELS− CENTRAL EAST PACIFIC− An organized route (See CARDINAL ALTITUDES.) system between the U.S. West Coast and Hawaii. CAT− CEP− (See CLEAR-AIR TURBULENCE.) (See CENTRAL EAST PACIFIC.) CATCH POINT− A fix/waypoint that serves as a CERAP− transition point from the high altitude waypoint (See COMBINED CENTER-RAPCON.) navigation structure to an arrival procedure (STAR) or the low altitude ground−based navigation CERTIFICATE OF WAIVER OR AUTHORIZA- structure. TION (COA)− An FAA grant of approval for a specific flight operation or airspace authorization or CEILING− The heights above the earth’s surface of waiver. the lowest layer of clouds or obscuring phenomena that is reported as “broken,” “overcast,” or CERTIFIED TOWER RADAR DISPLAY (CTRD)− “obscuration,” and not classified as “thin” or An FAA radar display certified for use in the NAS. “partial.” CFR− (See ICAO term CEILING.) (See CALL FOR RELEASE.) CEILING [ICAO]− The height above the ground or CHA water of the base of the lowest layer of cloud below (See CONTINGENCY HAZARD AREA) 6,000 meters (20,000 feet) covering more than half CHAFF− Thin, narrow metallic reflectors of various the sky. lengths and frequency responses, used to reflect radar CENTER− energy. These reflectors, when dropped from aircraft (See AIR ROUTE TRAFFIC CONTROL and allowed to drift downward, result in large targets CENTER.) on the radar display.

PCG C−1 Pilot/Controller Glossary 6/17/21

CHART SUPPLEMENT U.S.− A publication obtained and the pilot has established required visual designed primarily as a pilot’s operational manual reference to the airport. containing all airports, seaplane bases, and heliports (See CIRCLE TO RUNWAY.) open to the public including communications data, (See LANDING MINIMUMS.) navigational facilities, and certain special notices and (Refer to AIM.) procedures. This publication is issued in seven CIRCLE TO RUNWAY (RUNWAY NUMBER)− volumes according to geographical area. Used by ATC to inform the pilot that he/she must circle to land because the runway in use is other than CHARTED VFR FLYWAYS− Charted VFR Fly- the runway aligned with the instrument approach ways are flight paths recommended for use to bypass procedure. When the direction of the circling areas heavily traversed by large turbine-powered maneuver in relation to the airport/runway is aircraft. Pilot compliance with recommended required, the controller will state the direction (eight flyways and associated altitudes is strictly voluntary. cardinal compass points) and specify a left or right VFR Flyway Planning charts are published on the downwind or base leg as appropriate; e.g., “Cleared back of existing VFR Terminal Area charts. VOR Runway Three Six Approach circle to Runway Two Two,” or “Circle northwest of the airport for a CHARTED VISUAL FLIGHT PROCEDURE right downwind to Runway Two Two.” APPROACH− An approach conducted while (See CIRCLE-TO-LAND MANEUVER.) operating on an instrument flight rules (IFR) flight (See LANDING MINIMUMS.) plan which authorizes the pilot of an aircraft to (Refer to AIM.) proceed visually and clear of clouds to the airport via visual landmarks and other information depicted on CIRCLING APPROACH− a charted visual flight procedure. This approach must (See CIRCLE-TO-LAND MANEUVER.) be authorized and under the control of the appropriate CIRCLING MANEUVER− air traffic control facility. Weather minimums (See CIRCLE-TO-LAND MANEUVER.) required are depicted on the chart. CIRCLING MINIMA− (See LANDING MINIMUMS.) CHASE− An aircraft flown in proximity to another CLASS A AIRSPACE− aircraft normally to observe its performance during (See CONTROLLED AIRSPACE.) training or testing. CLASS B AIRSPACE− CHASE AIRCRAFT− (See CONTROLLED AIRSPACE.) (See CHASE.) CLASS C AIRSPACE− (See CONTROLLED AIRSPACE.) CHOP− A form of turbulence. CLASS D AIRSPACE− a. Light Chop– Turbulence that causes slight, (See CONTROLLED AIRSPACE.) rapid and somewhat rhythmic bumpiness without CLASS E AIRSPACE− appreciable changes in altitude or attitude. (See CONTROLLED AIRSPACE.) b. Moderate Chop– Turbulence similar to Light CLASS G AIRSPACE− Airspace that is not Chop but of greater intensity. It causes rapid bumps designated in 14 CFR Part 71 as Class A, Class B, or jolts without appreciable changes in aircraft Class C, Class D, or Class E controlled airspace is altitude or attitude. Class G (uncontrolled) airspace. (See TURBULENCE.) (See UNCONTROLLED AIRSPACE.) CLEAR AIR TURBULENCE (CAT)− Turbulence CIRCLE-TO-LAND MANEUVER− A maneuver encountered in air where no clouds are present. This initiated by the pilot to align the aircraft with a term is commonly applied to high-level turbulence runway for landing when a straight-in landing from associated with wind shear. CAT is often encountered an instrument approach is not possible or is not in the vicinity of the jet stream. desirable. At tower controlled airports, this maneuver (See WIND SHEAR.) is made only after ATC authorization has been (See JET STREAM.)

PCG C−2 6/17/21 Pilot/Controller Glossary

CLEAR OF THE RUNWAY− CLEARED (Type of) APPROACH− ATC authoriza- a. Taxiing aircraft, which is approaching a tion for an aircraft to execute a specific instrument runway, is clear of the runway when all parts of the approach procedure to an airport; e.g., “Cleared ILS aircraft are held short of the applicable runway Runway Three Six Approach.” holding position marking. (See APPROACH CLEARANCE.) (See INSTRUMENT APPROACH b. A pilot or controller may consider an aircraft, PROCEDURE.) which is exiting or crossing a runway, to be clear of (Refer to 14 CFR Part 91.) the runway when all parts of the aircraft are beyond (Refer to AIM.) the runway edge and there are no restrictions to its continued movement beyond the applicable runway CLEARED AS FILED− Means the aircraft is cleared holding position marking. to proceed in accordance with the route of flight filed in the flight plan. This clearance does not include the c. Pilots and controllers shall exercise good altitude, DP, or DP Transition. judgement to ensure that adequate separation exists (See REQUEST FULL ROUTE CLEARANCE.) between all aircraft on runways and taxiways at (Refer to AIM.) airports with inadequate runway edge lines or holding position markings. CLEARED FOR TAKEOFF− ATC authorization for an aircraft to depart. It is predicated on known CLEARANCE− traffic and known physical airport conditions. (See AIR TRAFFIC CLEARANCE.) CLEARED FOR THE OPTION− ATC authoriza- CLEARANCE LIMIT− The fix, point, or location to tion for an aircraft to make a touch-and-go, low which an aircraft is cleared when issued an air traffic approach, missed approach, stop and go, or full stop clearance. landing at the discretion of the pilot. It is normally (See ICAO term CLEARANCE LIMIT.) used in training so that an instructor can evaluate a student’s performance under changing situations. CLEARANCE LIMIT [ICAO]− The point to which Pilots should advise ATC if they decide to remain on an aircraft is granted an air traffic control clearance. the runway, of any delay in their stop and go, delay CLEARANCE VOID IF NOT OFF BY (TIME)− clearing the runway, or are unable to comply with the Used by ATC to advise an aircraft that the departure instruction(s). clearance is automatically canceled if takeoff is not (See OPTION APPROACH.) made prior to a specified time. The pilot must obtain (Refer to AIM.) a new clearance or cancel his/her IFR flight plan if not CLEARED THROUGH− ATC authorization for an off by the specified time. aircraft to make intermediate stops at specified (See ICAO term CLEARANCE VOID TIME.) airports without refiling a flight plan while en route to the clearance limit. CLEARANCE VOID TIME [ICAO]− A time specified by an air traffic control unit at which a CLEARED TO LAND− ATC authorization for an clearance ceases to be valid unless the aircraft aircraft to land. It is predicated on known traffic and concerned has already taken action to comply known physical airport conditions. therewith. CLEARWAY− An area beyond the takeoff runway CLEARED APPROACH− ATC authorization for an under the control of airport authorities within which aircraft to execute any standard or special instrument terrain or fixed obstacles may not extend above approach procedure for that airport. Normally, an specified limits. These areas may be required for aircraft will be cleared for a specific instrument certain turbine-powered operations and the size and approach procedure. upward slope of the clearway will differ depending on (See CLEARED (Type of) APPROACH.) when the aircraft was certificated. (See INSTRUMENT APPROACH (Refer to 14 CFR Part 1.) PROCEDURE.) CLIMB TO VFR− ATC authorization for an aircraft (Refer to 14 CFR Part 91.) to climb to VFR conditions within Class B, C, D, and (Refer to AIM.) E surface areas when the only weather limitation is

PCG C−3 Pilot/Controller Glossary 6/17/21

restricted visibility. The aircraft must remain clear of CMNPS− clouds while climbing to VFR. (See CANADIAN MINIMUM NAVIGATION (See SPECIAL VFR CONDITIONS.) PERFORMANCE SPECIFICATION AIRSPACE.) (Refer to AIM.) COA− CLIMBOUT− That portion of flight operation (See CERTIFICATE OF WAIVER OR between takeoff and the initial cruising altitude. AUTHORIZATION.) CLIMB VIA– An abbreviated ATC clearance that COASTAL FIX− A navigation aid or intersection requires compliance with the procedure lateral path, where an aircraft transitions between the domestic associated speed restrictions, and altitude restrictions route structure and the oceanic route structure. along the cleared route or procedure. CODES− The number assigned to a particular CLOSE PARALLEL RUNWAYS− Two parallel multiple pulse reply signal transmitted by a runways whose extended centerlines are separated by transponder. less than 4,300 feet and at least 3000 feet (750 feet for (See DISCRETE CODE.) SOIA operations) for which ATC is authorized to conduct simultaneous independent approach opera- COLD TEMPERATURE COMPENSATION− An tions. PRM and simultaneous close parallel appear in action on the part of the pilot to adjust an aircraft’s approach title. Dual communications, special pilot indicated altitude due to the effect of cold training, an Attention All Users Page (AAUP), NTZ temperatures on true altitude above terrain versus monitoring by displays that have aural and visual aircraft indicated altitude. The amount of alerting algorithms are required. A high update rate compensation required increases at a greater rate with surveillance sensor is required for certain runway or a decrease in temperature and increase in height approach course spacing. above the reporting station. CLOSED RUNWAY− A runway that is unusable for COLLABORATIVE TRAJECTORY OPTIONS aircraft operations. Only the airport management/ PROGRAM (CTOP)− CTOP is a traffic management military operations office can close a runway. program administered by the Air Traffic Control System Command Center (ATCSCC) that manages CLOSED TRAFFIC− Successive operations involv- demand through constrained airspace, while consid- ing takeoffs and landings or low approaches where ering operator preference with regard to both route the aircraft does not exit the traffic pattern. and delay as defined in a Trajectory Options Set (TOS). CLOUD− A cloud is a visible accumulation of minute water droplets and/or ice particles in the COMBINED CENTER-RAPCON− An air traffic atmosphere above the Earth’s surface. Cloud differs facility which combines the functions of an ARTCC from ground fog, fog, or ice fog only in that the latter and a radar approach control facility. are, by definition, in contact with the Earth’s surface. (See AIR ROUTE TRAFFIC CONTROL CLT− CENTER.) (See RADAR APPROACH CONTROL (See CALCULATED LANDING TIME.) FACILITY.) CLUTTER− In radar operations, clutter refers to the COMMON POINT− A significant point over which reception and visual display of radar returns caused two or more aircraft will report passing or have by precipitation, chaff, terrain, numerous aircraft reported passing before proceeding on the same or targets, or other phenomena. Such returns may limit diverging tracks. To establish/maintain longitudinal or preclude ATC from providing services based on separation, a controller may determine a common radar. point not originally in the aircraft’s flight plan and (See CHAFF.) then clear the aircraft to fly over the point. (See GROUND CLUTTER.) (See SIGNIFICANT POINT.) (See PRECIPITATION.) (See TARGET.) COMMON PORTION− (See ICAO term RADAR CLUTTER.) (See COMMON ROUTE.)

PCG C−4 6/17/21 Pilot/Controller Glossary

COMMON ROUTE− That segment of a North COMPOSITE FLIGHT PLAN− A flight plan which American Route between the inland navigation specifies VFR operation for one portion of flight and facility and the coastal fix. IFR for another portion. It is used primarily in military operations. OR (Refer to AIM.) COMMON ROUTE− Typically the portion of a COMPULSORY REPORTING POINTS− Reporting RNAV STAR between the en route transition end points which must be reported to ATC. They are point and the runway transition start point; however, designated on aeronautical charts by solid triangles or the common route may only consist of a single point filed in a flight plan as fixes selected to define direct that joins the en route and runway transitions. routes. These points are geographical locations which are defined by navigation aids/fixes. Pilots COMMON TRAFFIC ADVISORY FREQUENCY should discontinue position reporting over compul- (CTAF)− A frequency designed for the purpose of sory reporting points when informed by ATC that carrying out airport advisory practices while their aircraft is in “radar contact.” operating to or from an airport without an operating control tower. The CTAF may be a UNICOM, COMPUTER NAVIGATION FIX (CNF)− A Multicom, FSS, or tower frequency and is identified Computer Navigation Fix is a point defined by a in appropriate aeronautical publications. latitude/longitude coordinate and is required to (See DESIGNATED COMMON TRAFFIC support Performance−Based Navigation (PBN) ADVISORY FREQUENCY (CTAF) AREA.) operations. A five−letter identifier denoting a CNF (Refer to AC 90-66, Non−Towered Airport Flight can be found next to an “x” on en route charts and on Operations.) some approach charts. Eventually, all CNFs will be labeled and begin with the letters “CF” followed by COMPASS LOCATOR− A low power, low or three consonants (e.g., ‘CFWBG’). CNFs are not medium frequency (L/MF) radio beacon installed at recognized by ATC, are not contained in ATC fix or the site of the outer or middle marker of an instrument automation databases, and are not used for ATC landing system (ILS). It can be used for navigation at purposes. Pilots should not use CNFs for point−to− distances of approximately 15 miles or as authorized point navigation (e.g., proceed direct), filing a flight in the approach procedure. plan, or in aircraft/ATC communications. Use of a. Outer Compass Locator (LOM)− A compass CNFs has not been adopted or recognized by the locator installed at the site of the outer marker of an International Civil Aviation Organization (ICAO). instrument landing system. (REFER to AIM 1−1−17b5(i)(2), Global Positioning System (GPS). (See OUTER MARKER.) b. Middle Compass Locator (LMM)− A compass CONDITIONS NOT MONITORED− When an locator installed at the site of the middle marker of an airport operator cannot monitor the condition of the instrument landing system. movement area or airfield surface area, this (See MIDDLE MARKER.) information is issued as a NOTAM. Usually necessitated due to staffing, operating hours or other (See ICAO term LOCATOR.) mitigating factors associated with airport operations. COMPASS ROSE− A circle, graduated in degrees, CONFIDENCE MANEUVER− A confidence man- printed on some charts or marked on the ground at an euver consists of one or more turns, a climb or airport. It is used as a reference to either true or descent, or other maneuver to determine if the pilot magnetic direction. in command (PIC) is able to receive and comply with COMPLY WITH RESTRICTIONS− An ATC ATC instructions. instruction that requires an aircraft being vectored CONFLICT ALERT− A function of certain air traffic back onto an arrival or departure procedure to comply control automated systems designed to alert radar with all altitude and/or speed restrictions depicted on controllers to existing or pending situations between the procedure. This term may be used in lieu of tracked targets (known IFR or VFR aircraft) that repeating each remaining restriction that appears on require his/her immediate attention/action. the procedure. (See MODE C INTRUDER ALERT.)

PCG C−5 Pilot/Controller Glossary 6/17/21

CONFLICT RESOLUTION− The resolution of CONTAMINATED RUNWAY− A runway is potential conflictions between aircraft that are radar considered contaminated whenever standing water, identified and in communication with ATC by ice, snow, slush, frost in any form, heavy rubber, or ensuring that radar targets do not touch. Pertinent other substances are present. A runway is contami- traffic advisories shall be issued when this procedure nated with respect to rubber deposits or other is applied. friction-degrading substances when the average Note: This procedure shall not be provided utilizing friction value for any 500-foot segment of the runway mosaic radar systems. within the ALD fails below the recommended minimum friction level and the average friction value CONFORMANCE− The condition established when in the adjacent 500-foot segments falls below the an aircraft’s actual position is within the conformance maintenance planning friction level. region constructed around that aircraft at its position, CONTERMINOUS U.S.− The 48 adjoining States according to the trajectory associated with the and the District of Columbia. aircraft’s Current Plan. CONTINENTAL UNITED STATES− The 49 States CONFORMANCE REGION− A volume, bounded located on the continent of North America and the laterally, vertically, and longitudinally, within which District of Columbia. an aircraft must be at a given time in order to be in CONTINGENCY HAZARD AREA (CHA)− Used conformance with the Current Plan Trajectory for that by ATC. Areas of airspace that are defined and aircraft. At a given time, the conformance region is distributed in advance of a launch or reentry determined by the simultaneous application of the operation and are activated in response to a failure. lateral, vertical, and longitudinal conformance (See AIRCRAFT HAZARD AREA.) bounds for the aircraft at the position defined by time and aircraft’s trajectory. (See REFINED HAZARD AREA.) (See TRANSITIONAL HAZARD AREA.) CONSOLAN− A low frequency, long-distance CONTINUE− When used as a control instruction NAVAID used principally for transoceanic naviga- should be followed by another word or words tions. clarifying what is expected of the pilot. Example: “continue taxi,” “continue descent,” “continue CONTACT− inbound,” etc. a. Establish communication with (followed by the CONTROL AREA [ICAO]− A controlled airspace name of the facility and, if appropriate, the frequency extending upwards from a specified limit above the to be used). earth. b. A flight condition wherein the pilot ascertains the attitude of his/her aircraft and navigates by visual CONTROL SECTOR− An airspace area of defined reference to the surface. horizontal and vertical dimensions for which a controller or group of controllers has air traffic (See CONTACT APPROACH.) control responsibility, normally within an air route (See RADAR CONTACT.) traffic control center or an approach control facility. CONTACT APPROACH− An approach wherein an Sectors are established based on predominant traffic aircraft on an IFR flight plan, having an air traffic flows, altitude strata, and controller workload. Pilot control authorization, operating clear of clouds with communications during operations within a sector at least 1 mile flight visibility and a reasonable are normally maintained on discrete frequencies expectation of continuing to the destination airport in assigned to the sector. those conditions, may deviate from the instrument (See DISCRETE FREQUENCY.) approach procedure and proceed to the destination CONTROL SLASH− A radar beacon slash repre- airport by visual reference to the surface. This senting the actual position of the associated aircraft. approach will only be authorized when requested by Normally, the control slash is the one closest to the the pilot and the reported ground visibility at the interrogating radar beacon site. When ARTCC radar destination airport is at least 1 statute mile. is operating in narrowband (digitized) mode, the (Refer to AIM.) control slash is converted to a target symbol.

PCG C−6 6/17/21 Pilot/Controller Glossary

CONTROLLED AIRSPACE− An airspace of ments. Although the configuration of each Class C defined dimensions within which air traffic control area is individually tailored, the airspace usually service is provided to IFR flights and to VFR flights consists of a surface area with a 5 NM radius, a circle in accordance with the airspace classification. with a 10 NM radius that extends no lower than 1,200 feet up to 4,000 feet above the airport elevation, and a. Controlled airspace is a generic term that covers an outer area that is not charted. Each person must Class A, Class B, Class C, Class D, and Class E establish two-way radio communications with the airspace. ATC facility providing air traffic services prior to b. Controlled airspace is also that airspace within entering the airspace and thereafter maintain those which all aircraft operators are subject to certain pilot communications while within the airspace. VFR qualifications, operating rules, and equipment aircraft are only separated from IFR aircraft within requirements in 14 CFR Part 91 (for specific the airspace. operating requirements, please refer to 14 CFR (See OUTER AREA.) Part 91). For IFR operations in any class of controlled airspace, a pilot must file an IFR flight plan and 4. CLASS D− Generally, that airspace from the receive an appropriate ATC clearance. Each Class B, surface to 2,500 feet above the airport elevation Class C, and Class D airspace area designated for an (charted in MSL) surrounding those airports that airport contains at least one primary airport around have an operational control tower. The configuration which the airspace is designated (for specific of each Class D airspace area is individually tailored designations and descriptions of the airspace classes, and when instrument procedures are published, the please refer to 14 CFR Part 71). airspace will normally be designed to contain the procedures. Arrival extensions for instrument c. Controlled airspace in the United States is approach procedures may be Class D or Class E designated as follows: airspace. Unless otherwise authorized, each person must establish two-way radio communications with 1. CLASS A− Generally, that airspace from the ATC facility providing air traffic services prior to 18,000 feet MSL up to and including FL 600, entering the airspace and thereafter maintain those including the airspace overlying the waters within 12 nautical miles of the coast of the 48 contiguous States communications while in the airspace. No separation and Alaska. Unless otherwise authorized, all persons services are provided to VFR aircraft. must operate their aircraft under IFR. 5. CLASS E− Generally, if the airspace is not Class A, Class B, Class C, or Class D, and it is 2. CLASS B− Generally, that airspace from the controlled airspace, it is Class E airspace. Class E surface to 10,000 feet MSL surrounding the nation’s airspace extends upward from either the surface or a busiest airports in terms of airport operations or designated altitude to the overlying or adjacent passenger enplanements. The configuration of each controlled airspace. When designated as a surface Class B airspace area is individually tailored and area, the airspace will be configured to contain all consists of a surface area and two or more layers instrument procedures. Also in this class are Federal (some Class B airspace areas resemble upside-down airways, airspace beginning at either 700 or 1,200 wedding cakes), and is designed to contain all feet AGL used to transition to/from the terminal or en published instrument procedures once an aircraft route environment, en route domestic, and offshore enters the airspace. An ATC clearance is required for airspace areas designated below 18,000 feet MSL. all aircraft to operate in the area, and all aircraft that Unless designated at a lower altitude, Class E are so cleared receive separation services within the airspace begins at 14,500 MSL over the United airspace. The cloud clearance requirement for VFR States, including that airspace overlying the waters operations is “clear of clouds.” within 12 nautical miles of the coast of the 48 3. CLASS C− Generally, that airspace from the contiguous States and Alaska, up to, but not surface to 4,000 feet above the airport elevation including 18,000 feet MSL, and the airspace above (charted in MSL) surrounding those airports that FL 600. have an operational control tower, are serviced by a radar approach control, and that have a certain CONTROLLED AIRSPACE [ICAO]− An airspace number of IFR operations or passenger enplane- of defined dimensions within which air traffic control

PCG C−7 Pilot/Controller Glossary 6/17/21

service is provided to IFR flights and to VFR flights seconds of latitude and longitude, used to determine in accordance with the airspace classification. position or location. Note: Controlled airspace is a generic term which COORDINATION FIX− The fix in relation to which covers ATS airspace Classes A, B, C, D, and E. facilities will handoff, transfer control of an aircraft, CONTROLLED TIME OF ARRIVAL− Arrival time or coordinate flight progress data. For terminal assigned during a Traffic Management Program. This facilities, it may also serve as a clearance for arriving time may be modified due to adjustments or user aircraft. options. COPTER− CONTROLLER− (See HELICOPTER.) (See AIR TRAFFIC CONTROL SPECIALIST.) CORRECTION− An error has been made in the CONTROLLER [ICAO]− A person authorized to transmission and the correct version follows. provide air traffic control services. COUPLED APPROACH− An instrument approach performed by the aircraft autopilot, and/or visually CONTROLLER PILOT DATA LINK depicted on the flight director, which is receiving COMMUNICATIONS (CPDLC)− A two−way position information and/or steering commands from digital communications system that conveys textual onboard navigational equipment. In general, coupled air traffic control messages between controllers and non-precision approaches must be flown manually pilots using ground or satellite-based radio relay (autopilot disengaged) at altitudes lower than 50 feet stations. AGL below the minimum descent altitude, and CONVECTIVE SIGMET− A weather advisory coupled precision approaches must be flown concerning convective weather significant to the manually (autopilot disengaged) below 50 feet AGL safety of all aircraft. Convective SIGMETs are issued unless authorized to conduct autoland operations. for tornadoes, lines of thunderstorms, embedded Coupled instrument approaches are commonly flown thunderstorms of any intensity level, areas of to the allowable IFR weather minima established by thunderstorms greater than or equal to VIP level 4 the operator or PIC, or flown VFR for training and 4 with an area coverage of /10 (40%) or more, and hail safety. 3 /4 inch or greater. COURSE− (See AIRMET.) a. The intended direction of flight in the horizontal (See AWW.) plane measured in degrees from north. (See CWA.) (See SIGMET.) b. The ILS localizer signal pattern usually (Refer to AIM.) specified as the front course or the back course. (See BEARING.) CONVECTIVE SIGNIFICANT METEOROLOG- (See INSTRUMENT LANDING SYSTEM.) ICAL INFORMATION− (See RADIAL.) (See CONVECTIVE SIGMET.) CPDLC− COOPERATIVE SURVEILLANCE− Any surveil- (See CONTROLLER PILOT DATA LINK lance system, such as secondary surveillance radar COMMUNICATIONS.) (SSR), wide−area multilateration (WAM), or ADS− CPL [ICAO]− B, that is dependent upon the presence of certain (See ICAO term CURRENT FLIGHT PLAN.) equipment onboard the aircraft or vehicle to be detected. CRITICAL ENGINE− The engine which, upon (See AUTOMATIC DEPENDENT failure, would most adversely affect the performance SURVEILLANCE−BROADCAST.) or handling qualities of an aircraft. (See NON−COOPERATIVE SURVEILLANCE.) CROSS (FIX) AT (ALTITUDE)− Used by ATC (See RADAR.) when a specific altitude restriction at a specified fix (See WIDE AREA MULTILATERATION.) is required. COORDINATES− The intersection of lines of CROSS (FIX) AT OR ABOVE (ALTITUDE)− Used reference, usually expressed in degrees/minutes/ by ATC when an altitude restriction at a specified fix

PCG C−8 6/17/21 Pilot/Controller Glossary

is required. It does not prohibit the aircraft from b. An airport clearance limit at locations that are crossing the fix at a higher altitude than specified; within/below/outside controlled airspace and with- however, the higher altitude may not be one that will out a standard/special instrument approach violate a succeeding altitude restriction or altitude procedure. Such a clearance is NOT AUTHORIZA- assignment. TION for the pilot to descend under IFR conditions (See ALTITUDE RESTRICTION.) below the applicable minimum IFR altitude nor does (Refer to AIM.) it imply that ATC is exercising control over aircraft in Class G airspace; however, it provides a means for CROSS (FIX) AT OR BELOW (ALTITUDE)− the aircraft to proceed to destination airport, descend, Used by ATC when a maximum crossing altitude at and land in accordance with applicable CFRs a specific fix is required. It does not prohibit the governing VFR flight operations. Also, this provides aircraft from crossing the fix at a lower altitude; search and rescue protection until such time as the however, it must be at or above the minimum IFR IFR flight plan is closed. altitude. (See INSTRUMENT APPROACH (See ALTITUDE RESTRICTION.) PROCEDURE.) (See MINIMUM IFR ALTITUDES.) CRUISE CLIMB− A climb technique employed by (Refer to 14 CFR Part 91.) aircraft, usually at a constant power setting, resulting in an increase of altitude as the aircraft weight CROSSWIND− decreases. a. When used concerning the traffic pattern, the CRUISING ALTITUDE− An altitude or flight level word means “crosswind leg.” maintained during en route level flight. This is a (See TRAFFIC PATTERN.) constant altitude and should not be confused with a b. When used concerning wind conditions, the cruise clearance. word means a wind not parallel to the runway or the (See ALTITUDE.) path of an aircraft. (See ICAO term CRUISING LEVEL.) (See CROSSWIND COMPONENT.) CRUISING LEVEL− CROSSWIND COMPONENT− The wind compo- (See CRUISING ALTITUDE.) nent measured in knots at 90 degrees to the CRUISING LEVEL [ICAO]− A level maintained longitudinal axis of the runway. during a significant portion of a flight. CRUISE− Used in an ATC clearance to authorize a CT MESSAGE− An EDCT time generated by the pilot to conduct flight at any altitude from the ATCSCC to regulate traffic at arrival airports. minimum IFR altitude up to and including the Normally, a CT message is automatically transferred altitude specified in the clearance. The pilot may from the traffic management system computer to the level off at any intermediate altitude within this block NAS en route computer and appears as an EDCT. In of airspace. Climb/descent within the block is to be the event of a communication failure between the made at the discretion of the pilot. However, once the traffic management system computer and the NAS, pilot starts descent and verbally reports leaving an the CT message can be manually entered by the TMC altitude in the block, he/she may not return to that at the en route facility. altitude without additional ATC clearance. Further, it CTA− is approval for the pilot to proceed to and make an (See CONTROLLED TIME OF ARRIVAL.) approach at destination airport and can be used in (See ICAO term CONTROL AREA.) conjunction with: CTAF− a. An airport clearance limit at locations with a standard/special instrument approach procedure. The (See COMMON TRAFFIC ADVISORY FREQUENCY.) CFRs require that if an instrument letdown to an airport is necessary, the pilot shall make the letdown CTAS− in accordance with a standard/special instrument (See CENTER TRACON AUTOMATION approach procedure for that airport, or SYSTEM.)

PCG C−9 Pilot/Controller Glossary 6/17/21

CTOP− CURRENT PLAN− The ATC clearance the aircraft (See COLLABORATIVE TRAJECTORY has received and is expected to fly. OPTIONS PROGRAM) CVFP APPROACH− CTRD− (See CHARTED VISUAL FLIGHT PROCEDURE (See CERTIFIED TOWER RADAR DISPLAY.) APPROACH.) CURRENT FLIGHT PLAN [ICAO]− The flight CWA− plan, including changes, if any, brought about by (See CENTER WEATHER ADVISORY and subsequent clearances. WEATHER ADVISORY.)

PCG C−10 6/17/21 Pilot/Controller Glossary D

D−ATIS− 3. The required visual reference means that section of (See DIGITAL-AUTOMATIC TERMINAL the visual aids or of the approach area which should INFORMATION SERVICE.) have been in view for sufficient time for the pilot to have made an assessment of the aircraft position and D−ATIS [ICAO]− rate of change of position, in relation to the desired (See ICAO Term DATA LINK AUTOMATIC flight path. TERMINAL INFORMATION SERVICE.) DECISION ALTITUDE (DA)− A specified altitude DA [ICAO]− (mean sea level (MSL)) on an instrument approach (See ICAO Term DECISION procedure (ILS, GLS, vertically guided RNAV) at ALTITUDE/DECISION HEIGHT.) which the pilot must decide whether to continue the DAIR− approach or initiate an immediate missed approach if (See DIRECT ALTITUDE AND IDENTITY the pilot does not see the required visual references. READOUT.) DECISION HEIGHT (DH)− With respect to the DANGER AREA [ICAO]− An airspace of defined operation of aircraft, means the height at which a dimensions within which activities dangerous to the decision must be made during an ILS or PAR flight of aircraft may exist at specified times. instrument approach to either continue the approach Note: The term “Danger Area” is not used in or to execute a missed approach. reference to areas within the United States or any (See ICAO term DECISION of its possessions or territories. ALTITUDE/DECISION HEIGHT.) DAS− DECODER− The device used to decipher signals (See DELAY ASSIGNMENT.) received from ATCRBS transponders to effect their display as select codes. DATA BLOCK− (See CODES.) (See ALPHANUMERIC DISPLAY.) (See RADAR.) DATA LINK AUTOMATIC TERMINAL INFOR- DEFENSE AREA– Any airspace of the contiguous MATION SERVICE (D−ATIS) [ICAO]− The United States that is not an ADIZ in which the control provision of ATIS via data link. of aircraft is required for reasons of national security. DEAD RECKONING− Dead reckoning, as applied DEFENSE VISUAL FLIGHT RULES− Rules to flying, is the navigation of an airplane solely by applicable to flights within an ADIZ conducted under means of computations based on airspeed, course, the visual flight rules in 14 CFR Part 91. heading, wind direction, and speed, groundspeed, (See AIR DEFENSE IDENTIFICATION ZONE.) and elapsed time. (Refer to 14 CFR Part 91.) DECISION ALTITUDE/DECISION HEIGHT (Refer to 14 CFR Part 99.) [ICAO Annex 6]- A specified altitude or height (A/H) DELAY ASSIGNMENT (DAS)− Delays are distrib- in the precision approach at which a missed approach uted to aircraft based on the traffic management must be initiated if the required visual reference to program parameters. The delay assignment is continue the approach has not been established. calculated in 15−minute increments and appears as a 1. Decision altitude (DA) is referenced to mean sea table in Traffic Flow Management System (TFMS). level and decision height (DH) is referenced to the threshold elevation. DELAY INDEFINITE (REASON IF KNOWN) 2. Category II and III minima are expressed as a DH EXPECT FURTHER CLEARANCE (TIME)− and not a DA. Minima is assessed by reference to a Used by ATC to inform a pilot when an accurate radio altimeter and not a barometric altimeter, which estimate of the delay time and the reason for the delay makes the minima a DH. cannot immediately be determined; e.g., a disabled

PCG D−1 Pilot/Controller Glossary 6/17/21

aircraft on the runway, terminal or center area DESIRED TRACK− The planned or intended track saturation, weather below landing minimums, etc. between two waypoints. It is measured in degrees (See EXPECT FURTHER CLEARANCE (TIME).) from either magnetic or true north. The instantaneous angle may change from point to point along the great DELAY TIME− The amount of time that the arrival circle track between waypoints. must lose to cross the meter fix at the assigned meter fix time. This is the difference between ACLT and DETRESFA (DISTRESS PHASE) [ICAO]− The VTA. code word used to designate an emergency phase wherein there is reasonable certainty that an aircraft DEPARTURE CENTER− The ARTCC having and its occupants are threatened by grave and jurisdiction for the airspace that generates a flight to imminent danger or require immediate assistance. the impacted airport. DEVIATIONS− DEPARTURE CONTROL− A function of an a. A departure from a current clearance, such as an approach control facility providing air traffic control off course maneuver to avoid weather or turbulence. service for departing IFR and, under certain b. Where specifically authorized in the CFRs and conditions, VFR aircraft. requested by the pilot, ATC may permit pilots to (See APPROACH CONTROL FACILITY.) deviate from certain regulations. (Refer to AIM.) DH− DEPARTURE SEQUENCING PROGRAM− A (See DECISION HEIGHT.) program designed to assist in achieving a specified interval over a common point for departures. DH [ICAO]− (See ICAO Term DECISION ALTITUDE/ DEPARTURE TIME− The time an aircraft becomes DECISION HEIGHT.) airborne. DIGITAL-AUTOMATIC TERMINAL INFORMA- DESCEND VIA– An abbreviated ATC clearance that TION SERVICE (D-ATIS)− The service provides requires compliance with a published procedure text messages to aircraft, airlines, and other users lateral path and associated speed restrictions and outside the standard reception range of conventional provides a pilot-discretion descent to comply with ATIS via landline and data link communications to published altitude restrictions. the cockpit. Also, the service provides a computer− synthesized voice message that can be transmitted to DESCENT SPEED ADJUSTMENTS− Speed decel- all aircraft within range of existing transmitters. The eration calculations made to determine an accurate Terminal Data Link System (TDLS) D-ATIS VTA. These calculations start at the transition point application uses weather inputs from local automated and use arrival speed segments to the vertex. weather sources or manually entered meteorological DESIGNATED COMMON TRAFFIC ADVISORY data together with preprogrammed menus to provide FREQUENCY (CTAF) AREA− In Alaska, in standard information to users. Airports with D-ATIS addition to being designated for the purpose of capability are listed in the Chart Supplement U.S. carrying out airport advisory practices while DIGITAL TARGET− A computer−generated symbol operating to or from an airport without an operating representing an aircraft’s position, based on a primary airport traffic control tower, a CTAF may also be return or radar beacon reply, shown on a digital designated for the purpose of carrying out advisory display. practices for operations in and through areas with a high volume of VFR traffic. DIGITAL TERMINAL AUTOMATION SYSTEM (DTAS)− A system where digital radar and beacon DESIRED COURSE− data is presented on digital displays and the a. True− A predetermined desired course direction operational program monitors the system perfor- to be followed (measured in degrees from true north). mance on a real−time basis. b. Magnetic− A predetermined desired course DIGITIZED TARGET− A computer−generated direction to be followed (measured in degrees from indication shown on an analog radar display resulting local magnetic north). from a primary radar return or a radar beacon reply.

PCG D−2 6/17/21 Pilot/Controller Glossary

DIRECT− Straight line flight between two naviga- DISTRESS− A condition of being threatened by tional aids, fixes, points, or any combination thereof. serious and/or imminent danger and of requiring When used by pilots in describing off-airway routes, immediate assistance. points defining direct route segments become DIVE BRAKES− compulsory reporting points unless the aircraft is (See SPEED BRAKES.) under radar contact. DIVERSE VECTOR AREA− In a radar environ- DIRECTLY BEHIND− An aircraft is considered to ment, that area in which a prescribed departure route be operating directly behind when it is following the is not required as the only suitable route to avoid actual flight path of the lead aircraft over the surface obstacles. The area in which random radar vectors of the earth except when applying wake turbulence below the MVA/MIA, established in accordance with separation criteria. the TERPS criteria for diverse departures, obstacles and terrain avoidance, may be issued to departing DISCRETE BEACON CODE− aircraft. (See DISCRETE CODE.) DIVERSION (DVRSN)− Flights that are required to DISCRETE CODE− As used in the Air Traffic land at other than their original destination for Control Radar Beacon System (ATCRBS), any one reasons beyond the control of the pilot/company, e.g. of the 4096 selectable Mode 3/A aircraft transponder periods of significant weather. codes except those ending in zero zero; e.g., discrete DME− codes: 0010, 1201, 2317, 7777; nondiscrete codes: 0100, 1200, 7700. Nondiscrete codes are normally (See DISTANCE MEASURING EQUIPMENT.) reserved for radar facilities that are not equipped with DME FIX− A geographical position determined by discrete decoding capability and for other purposes reference to a navigational aid which provides such as emergencies (7700), VFR aircraft (1200), etc. distance and azimuth information. It is defined by a (See RADAR.) specific distance in nautical miles and a radial, (Refer to AIM.) azimuth, or course (i.e., localizer) in degrees magnetic from that aid. DISCRETE FREQUENCY− A separate radio (See DISTANCE MEASURING EQUIPMENT.) frequency for use in direct pilot-controller commu- (See FIX.) nications in air traffic control which reduces DME SEPARATION− Spacing of aircraft in terms of frequency congestion by controlling the number of distances (nautical miles) determined by reference to aircraft operating on a particular frequency at one distance measuring equipment (DME). time. Discrete frequencies are normally designated for each control sector in en route/terminal ATC (See DISTANCE MEASURING EQUIPMENT.) facilities. Discrete frequencies are listed in the Chart DOD FLIP− Department of Defense Flight Informa- Supplement U.S. and the DOD FLIP IFR En Route tion Publications used for flight planning, en route, Supplement. and terminal operations. FLIP is produced by the (See CONTROL SECTOR.) National Geospatial−Intelligence Agency (NGA) for world-wide use. United States Government Flight DISPLACED THRESHOLD− A threshold that is Information Publications (en route charts and located at a point on the runway other than the instrument approach procedure charts) are incorpo- designated beginning of the runway. rated in DOD FLIP for use in the National Airspace (See THRESHOLD.) System (NAS). (Refer to AIM.) DOMESTIC AIRSPACE− Airspace which overlies DISTANCE MEASURING EQUIPMENT (DME)− the continental land mass of the United States plus Equipment (airborne and ground) used to measure, in Hawaii and U.S. possessions. Domestic airspace nautical miles, the slant range distance of an aircraft extends to 12 miles offshore. from the DME navigational aid. DOMESTIC NOTICE− A special notice or notice (See TACAN.) containing graphics or plain language text pertaining (See VORTAC.) to almost every aspect of aviation, such as military

PCG D−3 Pilot/Controller Glossary 6/17/21

training areas, large scale sporting events, air show DTAS− information, Special Traffic Management Programs (See DIGITAL TERMINAL AUTOMATION (STMPs), and airport−specific information. These SYSTEM.) notices are applicable to operations within the United DUE REGARD− A phase of flight wherein an States and can be found on the Domestic Notices aircraft commander of a State-operated aircraft website. assumes responsibility to separate his/her aircraft DOWNBURST− A strong downdraft which induces from all other aircraft. an outburst of damaging winds on or near the ground. (See also FAA Order JO 7110.65, Para 1−2−1, Damaging winds, either straight or curved, are highly WORD MEANINGS.) divergent. The sizes of downbursts vary from 1/2 DUTY RUNWAY− mile or less to more than 10 miles. An intense (See RUNWAY IN USE/ACTIVE RUNWAY/DUTY downburst often causes widespread damage. Damag- RUNWAY.) ing winds, lasting 5 to 30 minutes, could reach speeds as high as 120 knots. DVA− (See DIVERSE VECTOR AREA.) DOWNWIND LEG− (See TRAFFIC PATTERN.) DVFR− (See DEFENSE VISUAL FLIGHT RULES.) DP− DVFR FLIGHT PLAN− A flight plan filed for a VFR (See INSTRUMENT DEPARTURE PROCEDURE.) aircraft which intends to operate in airspace within DRAG CHUTE− A parachute device installed on which the ready identification, location, and control certain aircraft which is deployed on landing roll to of aircraft are required in the interest of national assist in deceleration of the aircraft. security. DROP ZONE− Any pre-determined area upon which DVRSN− parachutists or objects land after making an (See DIVERSION.) intentional parachute jump or drop. DYNAMIC− Continuous review, evaluation, and (Refer to 14 CFR §105.3, Definitions) change to meet demands. DSP− DYNAMIC RESTRICTIONS− Those restrictions (See DEPARTURE SEQUENCING PROGRAM.) imposed by the local facility on an “as needed” basis DT− to manage unpredictable fluctuations in traffic (See DELAY TIME.) demands.

PCG D−4 6/17/21 Pilot/Controller Glossary E

EAS− an electronic means to provide a display of the (See EN ROUTE AUTOMATION SYSTEM.) forward external scene topography (the natural or man−made features of a place or region especially in EDCT− a way to show their relative positions and elevation) (See EXPECT DEPARTURE CLEARANCE through the use of imaging sensors, including but not TIME.) limited to forward−looking infrared, millimeter wave EDST− radiometry, millimeter wave radar, or low−light level (See EN ROUTE DECISION SUPPORT TOOL) image intensification. An EFVS includes the display element, sensors, computers and power supplies, EFC− indications, and controls. An operator’s authoriza- (See EXPECT FURTHER CLEARANCE (TIME).) tion to conduct an EFVS operation may have provisions which allow pilots to conduct IAPs when ELT− the reported weather is below minimums prescribed (See EMERGENCY LOCATOR TRANSMITTER.) on the IAP to be flown. EMERGENCY− A distress or an urgency condition. EN ROUTE AIR TRAFFIC CONTROL SER- EMERGENCY AUTOLAND SYSTEM− This VICES− Air traffic control service provided aircraft system, if activated, will determine an optimal on IFR flight plans, generally by centers, when these airport, plot a course, broadcast the aircraft’s aircraft are operating between departure and intentions, fly to the airport, land, and (depending on destination terminal areas. When equipment, capa- the model) shut down the engines. Though the system bilities, and controller workload permit, certain will broadcast the aircraft’s intentions, the controller advisory/assistance services may be provided to VFR should assume that transmissions to the aircraft will aircraft. not be acknowledged. (See AIR ROUTE TRAFFIC CONTROL CENTER.) EMERGENCY DESCENT MODE− This automated system senses conditions conducive to hypoxia (Refer to AIM.) (cabin depressurization). If an aircraft is equipped EN ROUTE AUTOMATION SYSTEM (EAS)− The and the system is activated, it is designed to turn the complex integrated environment consisting of aircraft up to 90 degrees, then descend to a lower situation display systems, surveillance systems and altitude and level off, giving the pilot(s) time to flight data processing, remote devices, decision recover. support tools, and the related communications EMERGENCY LOCATOR TRANSMITTER equipment that form the heart of the automated IFR (ELT)− A radio transmitter attached to the aircraft air traffic control system. It interfaces with automated structure which operates from its own power source terminal systems and is used in the control of en route on 121.5 MHz and 243.0 MHz. It aids in locating IFR aircraft. downed aircraft by radiating a downward sweeping (Refer to AIM.) audio tone, 2-4 times per second. It is designed to EN ROUTE CHARTS− function without human action after an accident. (See AERONAUTICAL CHART.) (Refer to 14 CFR Part 91.) (Refer to AIM.) EN ROUTE DECISION SUPPORT TOOL (EDST)− An automated tool provided at each Radar Associate E-MSAW− position in selected En Route facilities. This tool (See EN ROUTE MINIMUM SAFE ALTITUDE utilizes flight and radar data to determine present and WARNING.) future trajectories for all active and proposal aircraft ENHANCED FLIGHT VISION SYSTEM (EFVS)− and provides enhanced automated flight data An EFVS is an installed aircraft system which uses management.

PCG E−1 Pilot/Controller Glossary 6/17/21

EN ROUTE DESCENT− Descent from the en route expiration time. Any NOTAM which includes an cruising altitude which takes place along the route of “EST” will be auto−expired at the designated flight. expiration time. EN ROUTE HIGH ALTITUDE CHARTS− ESTIMATED ELAPSED TIME [ICAO]− The (See AERONAUTICAL CHART.) estimated time required to proceed from one significant point to another. EN ROUTE LOW ALTITUDE CHARTS− (See ICAO Term TOTAL ESTIMATED ELAPSED (See AERONAUTICAL CHART.) TIME.) EN ROUTE MINIMUM SAFE ALTITUDE WARN- ESTIMATED OFF-BLOCK TIME [ICAO]− The ING (E−MSAW)− A function of the EAS that aids the estimated time at which the aircraft will commence controller by providing an alert when a tracked movement associated with departure. aircraft is below or predicted by the computer to go below a predetermined minimum IFR altitude ESTIMATED POSITION ERROR (EPE)− (MIA). (See Required Navigation Performance) EN ROUTE SPACING PROGRAM (ESP)− A ESTIMATED TIME OF ARRIVAL− The time the program designed to assist the exit sector in flight is estimated to arrive at the gate (scheduled achieving the required in-trail spacing. operators) or the actual runway on times for nonscheduled operators. EN ROUTE TRANSITION− ESTIMATED TIME EN ROUTE− The estimated a. Conventional STARs/SIDs. The portion of a flying time from departure point to destination SID/STAR that connects to one or more en route (lift-off to touchdown). airway/jet route. b. RNAV STARs/SIDs. The portion of a STAR ETA− preceding the common route or point, or for a SID the (See ESTIMATED TIME OF ARRIVAL.) portion following, that is coded for a specific en route ETE− fix, airway or jet route. (See ESTIMATED TIME EN ROUTE.) ESP− EXECUTE MISSED APPROACH− Instructions (See EN ROUTE SPACING PROGRAM.) issued to a pilot making an instrument approach EST− which means continue inbound to the missed (See ESTIMATED.) approach point and execute the missed approach procedure as described on the Instrument Approach ESTABLISHED− To be stable or fixed at an altitude Procedure Chart or as previously assigned by ATC. or on a course, route, route segment, heading, The pilot may climb immediately to the altitude instrument approach or departure procedure, etc. specified in the missed approach procedure upon ESTABLISHED ON RNP (EoR) CONCEPT– A making a missed approach. No turns should be system of authorized instrument approaches, ATC initiated prior to reaching the missed approach point. procedures, surveillance, and communication re- When conducting an ASR or PAR approach, execute quirements that allow aircraft operations to be safely the assigned missed approach procedure immediately conducted with approved reduced separation criteria upon receiving instructions to “execute missed once aircraft are established on a PBN segment of a approach.” published instrument flight procedure. (Refer to AIM.) ESTIMATED (EST)−When used in NOTAMs EXPECT (ALTITUDE) AT (TIME) or (FIX)− Used “EST” is a contraction that is used by the issuing under certain conditions to provide a pilot with an authority only when the condition is expected to altitude to be used in the event of two-way return to service prior to the expiration time. Using communications failure. It also provides altitude “EST” lets the user know that this NOTAM has the information to assist the pilot in planning. possibility of returning to service earlier than the (Refer to AIM.)

PCG E−2 6/17/21 Pilot/Controller Glossary

EXPECT DEPARTURE CLEARANCE TIME pilot of the routing he/she can expect if any part of the (EDCT)− The runway release time assigned to an route beyond a short range clearance limit differs aircraft in a traffic management program and shown from that filed. on the flight progress strip as an EDCT. (See GROUND DELAY PROGRAM.) EXPEDITE− Used by ATC when prompt compliance is required to avoid the development of an EXPECT FURTHER CLEARANCE (TIME)− The imminent situation. Expedite climb/descent normal- time a pilot can expect to receive clearance beyond a ly indicates to a pilot that the approximate best rate clearance limit. of climb/descent should be used without requiring an EXPECT FURTHER CLEARANCE VIA (AIR- exceptional change in aircraft handling characteris- WAYS, ROUTES OR FIXES)− Used to inform a tics.

PCG E−3

6/17/21 Pilot/Controller Glossary F

FAF− FIELD ELEVATION− (See FINAL APPROACH FIX.) (See AIRPORT ELEVATION.) FALLEN HERO– Remains of fallen members of the FILED− Normally used in conjunction with flight United States military are often returned home by plans, meaning a flight plan has been submitted to aircraft. These flights may be identified with the ATC. phrase “FALLEN HERO” added to the remarks FILED EN ROUTE DELAY− Any of the following section of the flight plan, or they may be transmitted preplanned delays at points/areas along the route of via air/ground communications. If able, these flights flight which require special flight plan filing and will receive priority handling. handling techniques. FAST FILE− An FSS system whereby a pilot files a a. Terminal Area Delay. A delay within a terminal flight plan via telephone that is recorded and later area for touch-and-go, low approach, or other transcribed for transmission to the appropriate air terminal area activity. traffic facility. (Alaska only.) b. Special Use Airspace Delay. A delay within a Military Operations Area, Restricted Area, Warning FAWP− Final Approach Waypoint Area, or ATC Assigned Airspace. FCLT− c. Aerial Refueling Delay. A delay within an (See FREEZE CALCULATED LANDING TIME.) Aerial Refueling Track or Anchor. FILED FLIGHT PLAN− The flight plan as filed with FEATHERED PROPELLER− A propeller whose an ATS unit by the pilot or his/her designated blades have been rotated so that the leading and representative without any subsequent changes or trailing edges are nearly parallel with the aircraft clearances. flight path to stop or minimize drag and engine rotation. Normally used to indicate shutdown of a FINAL− Commonly used to mean that an aircraft is reciprocating or turboprop engine due to malfunc- on the final approach course or is aligned with a tion. landing area. (See FINAL APPROACH COURSE.) FEDERAL AIRWAYS− (See FINAL APPROACH-IFR.) (See LOW ALTITUDE AIRWAY STRUCTURE.) (See SEGMENTS OF AN INSTRUMENT FEEDER FIX− The fix depicted on Instrument APPROACH PROCEDURE.) Approach Procedure Charts which establishes the FINAL APPROACH [ICAO]− That part of an starting point of the feeder route. instrument approach procedure which commences at the specified final approach fix or point, or where FEEDER ROUTE− A route depicted on instrument such a fix or point is not specified. approach procedure charts to designate routes for a. At the end of the last procedure turn, base turn aircraft to proceed from the en route structure to the or inbound turn of a racetrack procedure, if specified; initial approach fix (IAF). or (See INSTRUMENT APPROACH PROCEDURE.) b. At the point of interception of the last track specified in the approach procedure; and ends at a FERRY FLIGHT− A flight for the purpose of: point in the vicinity of an aerodrome from which: a. Returning an aircraft to base. 1. A landing can be made; or b. Delivering an aircraft from one location to 2. A missed approach procedure is initiated. another. FINAL APPROACH COURSE− A bearing/radial/ c. Moving an aircraft to and from a maintenance track of an instrument approach leading to a runway base. Ferry flights, under certain conditions, may be or an extended runway centerline all without regard conducted under terms of a special flight permit. to distance.

PCG F−1 Pilot/Controller Glossary 6/17/21

FINAL APPROACH FIX− The fix from which the FINAL CONTROLLER− The controller providing final approach (IFR) to an airport is executed and information and final approach guidance during PAR which identifies the beginning of the final approach and ASR approaches utilizing radar equipment. segment. It is designated on Government charts by (See RADAR APPROACH.) the Maltese Cross symbol for nonprecision FINAL GUARD SERVICE− A value added service approaches and the lightning bolt symbol, provided in conjunction with LAA/RAA only during designating the PFAF, for precision approaches; or periods of significant and fast changing weather when ATC directs a lower-than-published conditions that may affect landing and takeoff glideslope/path or vertical path intercept altitude, it is operations. the resultant actual point of the glideslope/path or vertical path intercept. FINAL MONITOR AID− A high resolution color (See FINAL APPROACH POINT.) display that is equipped with the controller alert (See GLIDESLOPE INTERCEPT ALTITUDE.) system hardware/software used to monitor the no transgression zone (NTZ) during simultaneous (See SEGMENTS OF AN INSTRUMENT APPROACH PROCEDURE.) parallel approach operations. The display includes alert algorithms providing the target predictors, a color change alert when a target penetrates or is FINAL APPROACH-IFR− The flight path of an predicted to penetrate the no transgression zone aircraft which is inbound to an airport on a final (NTZ), synthesized voice alerts, and digital mapping. instrument approach course, beginning at the final approach fix or point and extending to the airport or (See RADAR APPROACH.) the point where a circle-to-land maneuver or a missed FINAL MONITOR CONTROLLER− Air Traffic approach is executed. Control Specialist assigned to radar monitor the (See FINAL APPROACH COURSE.) flight path of aircraft during simultaneous parallel (See FINAL APPROACH FIX.) (approach courses spaced less than 9000 feet/9200 feet above 5000 feet) and simultaneous close parallel (See FINAL APPROACH POINT.) approach operations. Each runway is assigned a final (See SEGMENTS OF AN INSTRUMENT monitor controller during simultaneous parallel and APPROACH PROCEDURE.) simultaneous close parallel ILS approaches. (See ICAO term FINAL APPROACH.) FIR− FINAL APPROACH POINT− The point, applicable (See FLIGHT INFORMATION REGION.) only to a nonprecision approach with no depicted FIRST TIER CENTER− An ARTCC immediately FAF (such as an on airport VOR), where the aircraft adjacent to the impacted center. is established inbound on the final approach course from the procedure turn and where the final approach FIS−B− descent may be commenced. The FAP serves as the (See FLIGHT INFORMATION FAF and identifies the beginning of the final SERVICE−BROADCAST.) approach segment. FIX− A geographical position determined by visual (See FINAL APPROACH FIX.) reference to the surface, by reference to one or more (See SEGMENTS OF AN INSTRUMENT radio NAVAIDs, by celestial plotting, or by another APPROACH PROCEDURE.) navigational device. FIX BALANCING− A process whereby aircraft are FINAL APPROACH SEGMENT− evenly distributed over several available arrival fixes (See SEGMENTS OF AN INSTRUMENT reducing delays and controller workload. APPROACH PROCEDURE.) FLAG− A warning device incorporated in certain FINAL APPROACH SEGMENT [ICAO]− That airborne navigation and flight instruments indicating segment of an instrument approach procedure in that: which alignment and descent for landing are a. Instruments are inoperative or otherwise not accomplished. operating satisfactorily, or

PCG F−2 6/17/21 Pilot/Controller Glossary

b. Signal strength or quality of the received signal network over the UAT data link that operates on 978 falls below acceptable values. MHz. The FIS−B system provides pilots and flight crews of properly equipped aircraft with a cockpit FLAG ALARM− display of certain aviation weather and aeronautical (See FLAG.) information.

FLAMEOUT− An emergency condition caused by a FLIGHT INSPECTION− Inflight investigation and loss of engine power. evaluation of a navigational aid to determine whether FLAMEOUT PATTERN− An approach normally it meets established tolerances. conducted by a single-engine military aircraft (See FLIGHT CHECK.) experiencing loss or anticipating loss of engine (See NAVIGATIONAL AID.) power or control. The standard overhead approach starts at a relatively high altitude over a runway FLIGHT LEVEL− A level of constant atmospheric (“high key”) followed by a continuous 180 degree pressure related to a reference datum of 29.92 inches turn to a high, wide position (“low key”) followed by of mercury. Each is stated in three digits that represent a continuous 180 degree turn final. The standard hundreds of feet. For example, flight level (FL) 250 straight-in pattern starts at a point that results in a represents a barometric altimeter indication of straight-in approach with a high rate of descent to the 25,000 feet; FL 255, an indication of 25,500 feet. runway. Flameout approaches terminate in the type (See ICAO term FLIGHT LEVEL.) approach requested by the pilot (normally fullstop). FLIGHT LEVEL [ICAO]− A surface of constant FLIGHT CHECK− A call sign prefix used by FAA atmospheric pressure which is related to a specific aircraft engaged in flight inspection/certification of pressure datum, 1013.2 hPa (1013.2 mb), and is navigational aids and flight procedures. The word separated from other such surfaces by specific “recorded” may be added as a suffix; e.g., “Flight pressure intervals. Check 320 recorded” to indicate that an automated Note 1: A pressure type altimeter calibrated in flight inspection is in progress in terminal areas. accordance with the standard atmosphere: (See FLIGHT INSPECTION.) a. When set to a QNH altimeter setting, will (Refer to AIM.) indicate altitude; b. When set to a QFE altimeter setting, will FLIGHT FOLLOWING− indicate height above the QFE reference datum; (See TRAFFIC ADVISORIES.) and c. When set to a pressure of 1013.2 hPa FLIGHT INFORMATION REGION− An airspace of (1013.2 mb), may be used to indicate flight levels. defined dimensions within which Flight Information Note 2: The terms ‘height’ and ‘altitude,’ used in Service and Alerting Service are provided. Note 1 above, indicate altimetric rather than a. Flight Information Service. A service provided geometric heights and altitudes. for the purpose of giving advice and information useful for the safe and efficient conduct of flights. FLIGHT LINE− A term used to describe the precise movement of a civil photogrammetric aircraft along b. Alerting Service. A service provided to notify a predetermined course(s) at a predetermined altitude appropriate organizations regarding aircraft in need during the actual photographic run. of search and rescue aid and to assist such organizations as required. FLIGHT MANAGEMENT SYSTEMS− A comput- FLIGHT INFORMATION SERVICE− A service er system that uses a large data base to allow routes provided for the purpose of giving advice and to be preprogrammed and fed into the system by information useful for the safe and efficient conduct means of a data loader. The system is constantly of flights. updated with respect to position accuracy by reference to conventional navigation aids. The FLIGHT INFORMATION SERVICE− sophisticated program and its associated data base BROADCAST (FIS−B)− A ground broadcast service ensures that the most appropriate aids are automati- provided through the ADS−B Broadcast Services cally selected during the information update cycle.

PCG F−3 Pilot/Controller Glossary 6/17/21

FLIGHT PATH− A line, course, or track along which FLIGHT STANDARDS DISTRICT OFFICE− An an aircraft is flying or intended to be flown. FAA field office serving an assigned geographical (See COURSE.) area and staffed with Flight Standards personnel who (See TRACK.) serve the aviation industry and the general public on matters relating to the certification and operation of FLIGHT PLAN− Specified information relating to air carrier and general aviation aircraft. Activities the intended flight of an aircraft that is filed include general surveillance of operational safety, electronically, orally, or in writing with an FSS, certification of airmen and aircraft, accident third−party vendor, or an ATC facility. prevention, investigation, enforcement, etc. (See FAST FILE.) FLIGHT TERMINATION− The intentional and (See FILED.) deliberate process of terminating the flight of a UA in (Refer to AIM.) the event of an unrecoverable lost link, loss of FLIGHT PLAN AREA (FPA)− The geographical control, or other failure that compromises the safety area assigned to a flight service station (FSS) for the of flight. purpose of establishing primary responsibility for FLIGHT TEST− A flight for the purpose of: services that may include search and rescue for VFR a. Investigating the operation/flight characteris- aircraft, issuance of NOTAMs, pilot briefings, tics of an aircraft or aircraft component. inflight services, broadcast services, emergency services, flight data processing, international opera- b. Evaluating an applicant for a pilot certificate or tions, and aviation weather services. Large rating. consolidated FSS facilities may combine FPAs into FLIGHT VISIBILITY− larger areas of responsibility (AOR). (See VISIBILITY.) (See FLIGHT SERVICE STATION.) FLIP− (See TIE-IN FACILITY.) (See DOD FLIP.) FLIGHT RECORDER− A general term applied to FLY-BY WAYPOINT− A fly-by waypoint requires any instrument or device that records information the use of turn anticipation to avoid overshoot of the about the performance of an aircraft in flight or about next flight segment. conditions encountered in flight. Flight recorders may make records of airspeed, outside air FLY HEADING (DEGREES)− Informs the pilot of temperature, vertical acceleration, engine RPM, the heading he/she should fly. The pilot may have to manifold pressure, and other pertinent variables for a turn to, or continue on, a specific compass direction given flight. in order to comply with the instructions. The pilot is expected to turn in the shorter direction to the heading (See ICAO term FLIGHT RECORDER.) unless otherwise instructed by ATC. FLIGHT RECORDER [ICAO]− Any type of FLY-OVER WAYPOINT− A fly-over waypoint recorder installed in the aircraft for the purpose of precludes any turn until the waypoint is overflown complementing accident/incident investigation. and is followed by an intercept maneuver of the next Note: See Annex 6 Part I, for specifications relating flight segment. to flight recorders. FLY VISUAL TO AIRPORT− FLIGHT SERVICE STATION (FSS)− An air traffic (See PUBLISHED INSTRUMENT APPROACH facility which provides pilot briefings, flight plan PROCEDURE VISUAL SEGMENT.) processing, en route flight advisories, search and FLYAWAY− When the pilot is unable to effect control rescue services, and assistance to lost aircraft and of the aircraft and, as a result, the UA is not operating aircraft in emergency situations. FSS also relay ATC in a predictable or planned manner. clearances, process Notices to Airmen, and broadcast aviation weather and aeronautical information. In FMA− Alaska, FSS provide Airport Advisory Services. (See FINAL MONITOR AID.) (See FLIGHT PLAN AREA.) FMS− (See TIE-IN FACILITY.) (See FLIGHT MANAGEMENT SYSTEM.)

PCG F−4 6/17/21 Pilot/Controller Glossary

FORMATION FLIGHT− More than one aircraft FREEZE SPEED PARAMETER− A speed adapted which, by prior arrangement between the pilots, for each aircraft to determine fast and slow aircraft. operate as a single aircraft with regard to navigation Fast aircraft freeze on parameter FCLT and slow and position reporting. Separation between aircraft aircraft freeze on parameter MLDI. within the formation is the responsibility of the flight FRICTION MEASUREMENT− A measurement of leader and the pilots of the other aircraft in the flight. the friction characteristics of the runway pavement This includes transition periods when aircraft within surface using continuous self-watering friction the formation are maneuvering to attain separation measurement equipment in accordance with the from each other to effect individual control and specifications, procedures and schedules contained during join-up and breakaway. in AC 150/5320−12, Measurement, Construction, a. A standard formation is one in which a and Maintenance of Skid Resistant Airport Pavement proximity of no more than 1 mile laterally or Surfaces. longitudinally and within 100 feet vertically from the FSDO− flight leader is maintained by each wingman. (See FLIGHT STANDARDS DISTRICT OFFICE.) b. Nonstandard formations are those operating under any of the following conditions: FSPD− (See FREEZE SPEED PARAMETER.) 1. When the flight leader has requested and ATC has approved other than standard formation FSS− dimensions. (See FLIGHT SERVICE STATION.) 2. When operating within an authorized altitude FUEL DUMPING− Airborne release of usable fuel. reservation (ALTRV) or under the provisions of a This does not include the dropping of fuel tanks. letter of agreement. (See JETTISONING OF EXTERNAL STORES.) 3. When the operations are conducted in FUEL REMAINING− A phrase used by either pilots airspace specifically designed for a special activity. or controllers when relating to the fuel remaining on (See ALTITUDE RESERVATION.) board until actual fuel exhaustion. When transmitting (Refer to 14 CFR Part 91.) such information in response to either a controller question or pilot initiated cautionary advisory to air FRC− traffic control, pilots will state the APPROXIMATE (See REQUEST FULL ROUTE CLEARANCE.) NUMBER OF MINUTES the flight can continue FREEZE/FROZEN− Terms used in referring to with the fuel remaining. All reserve fuel SHOULD arrivals which have been assigned ACLTs and to the BE INCLUDED in the time stated, as should an lists in which they are displayed. allowance for established fuel gauge system error. FUEL SIPHONING− Unintentional release of fuel FREEZE CALCULATED LANDING TIME− A caused by overflow, puncture, loose cap, etc. dynamic parameter number of minutes prior to the meter fix calculated time of arrival for each aircraft FUEL VENTING− when the TCLT is frozen and becomes an ACLT (i.e., (See FUEL SIPHONING.) the VTA is updated and consequently the TCLT is FUSED TARGET- modified as appropriate until FCLT minutes prior to (See DIGITAL TARGET) meter fix calculated time of arrival, at which time updating is suspended and an ACLT and a frozen FUSION [STARS]- the combination of all available meter fix crossing time (MFT) is assigned). surveillance sources (airport surveillance radar [ASR], air route surveillance radar [ARSR], ADS-B, FREEZE HORIZON− The time or point at which an etc.) into the display of a single tracked target for air aircraft’s STA becomes fixed and no longer fluctuates traffic control separation services. FUSION is the with each radar update. This setting ensures a equivalent of the current single-sensor radar display. constant time for each aircraft, necessary for the FUSION performance is characteristic of a metering controller to plan his/her delay technique. single-sensor radar display system. Terminal areas This setting can be either in distance from the meter use mono-pulse secondary surveillance radar (ASR fix or a prescribed flying time to the meter fix. 9, Mode S or ASR 11, MSSR).

PCG F−5

6/17/21 Pilot/Controller Glossary G

GATE HOLD PROCEDURES− Procedures at the visual portion of an instrument approach and selected airports to hold aircraft at the gate or other landing. ground location whenever departure delays exceed or c. PAR. Used by ATC to inform an aircraft making are anticipated to exceed 15 minutes. The sequence a PAR approach of its vertical position (elevation) for departure will be maintained in accordance with relative to the descent profile. initial call−up unless modified by flow control (See ICAO term GLIDEPATH.) restrictions. Pilots should monitor the ground control/clearance delivery frequency for engine GLIDESLOPE INTERCEPT ALTITUDE− The start/taxi advisories or new proposed start/taxi time published minimum altitude to intercept the if the delay changes. glideslope in the intermediate segment of an GCA− instrument approach. Government charts use the lightning bolt symbol to identify this intercept point. (See GROUND CONTROLLED APPROACH.) This intersection is called the Precise Final Approach GDP− fix (PFAF). ATC directs a higher altitude, the (See GROUND DELAY PROGRAM.) resultant intercept becomes the PFAF. (See FINAL APPROACH FIX.) GENERAL AVIATION− That portion of civil (See SEGMENTS OF AN INSTRUMENT aviation that does not include scheduled or APPROACH PROCEDURE.) unscheduled air carriers or commercial space operations. GLOBAL NAVIGATION SATELLITE SYSTEM (See ICAO term GENERAL AVIATION.) (GNSS)− GNSS refers collectively to the worldwide positioning, navigation, and timing determination GENERAL AVIATION [ICAO]− All civil aviation capability available from one or more satellite operations other than scheduled air services and constellations. A GNSS constellation may be nonscheduled air transport operations for remunera- augmented by ground stations and/or geostationary tion or hire. satellites to improve integrity and position accuracy. GEO MAP− The digitized map markings associated (See GROUND−BASED AUGMENTATION with the ASR-9 Radar System. SYSTEM.) (See SATELLITE−BASED AUGMENTATION GLIDEPATH− SYSTEM.) (See GLIDESLOPE.) GLOBAL NAVIGATION SATELLITE SYSTEM GLIDEPATH [ICAO]− A descent profile determined MINIMUM EN ROUTE IFR ALTITUDE (GNSS for vertical guidance during a final approach. MEA)− The minimum en route IFR altitude on a published ATS route or route segment which assures GLIDEPATH INTERCEPT ALTITUDE− acceptable Global Navigation Satellite System (See GLIDESLOPE INTERCEPT ALTITUDE.) reception and meets obstacle clearance requirements. GLIDESLOPE− Provides vertical guidance for (Refer to 14 CFR Part 91.) aircraft during approach and landing. The glideslope/ (Refer to 14 CFR Part 95.) glidepath is based on the following: GLOBAL POSITIONING SYSTEM (GPS)− GPS a. Electronic components emitting signals which refers to the worldwide positioning, navigation and provide vertical guidance by reference to airborne timing determination capability available from the instruments during instrument approaches such as U.S. satellite constellation. The service provided by ILS; or, GPS for civil use is defined in the GPS Standard b. Visual ground aids, such as VASI, which Positioning System Performance Standard. GPS is provide vertical guidance for a VFR approach or for composed of space, control, and user elements.

PCG G−1 Pilot/Controller Glossary 6/17/21

GNSS [ICAO]− GROUND BASED AUGMENTATION SYSTEM (See GLOBAL NAVIGATION SATELLITE (GBAS) LANDING SYSTEM (GLS)- A type of SYSTEM.) precision IAP based on local augmentation of GNSS data using a single GBAS station to transmit locally GNSS MEA− corrected GNSS data, integrity parameters and (See GLOBAL NAVIGATION SATELLITE approach information. This improves the accuracy of SYSTEM MINIMUM EN ROUTE IFR aircraft GNSS receivers’ signal in space, enabling the ALTITUDE.) pilot to fly a precision approach with much greater GO AHEAD− Proceed with your message. Not to be flexibility, reliability and complexity. The GLS used for any other purpose. procedure is published on standard IAP charts, features the title GLS with the designated runway and GO AROUND− Instructions for a pilot to abandon minima as low as 200 feet DA. Future plans are his/her approach to landing. Additional instructions expected to support Cat II and CAT III operations. may follow. Unless otherwise advised by ATC, a VFR aircraft or an aircraft conducting visual GROUND CLUTTER− A pattern produced on the approach should overfly the runway while climbing radar scope by ground returns which may degrade to traffic pattern altitude and enter the traffic pattern other radar returns in the affected area. The effect of via the crosswind leg. A pilot on an IFR flight plan ground clutter is minimized by the use of moving making an instrument approach should execute the target indicator (MTI) circuits in the radar equipment published missed approach procedure or proceed as resulting in a radar presentation which displays only instructed by ATC; e.g., “Go around” (additional targets which are in motion. instructions if required). (See CLUTTER.) (See LOW APPROACH.) GROUND COMMUNICATION OUTLET (GCO)− (See MISSED APPROACH.) An unstaffed, remotely controlled, ground/ground GPD− communications facility. Pilots at uncontrolled (See GRAPHIC PLAN DISPLAY.) airports may contact ATC and FSS via VHF radio to a telephone connection. If the connection goes to GPS− ATC, the pilot can obtain an IFR clearance or close (See GLOBAL POSITIONING SYSTEM.) an IFR flight plan. If the connection goes to Flight Service, the pilot can open or close a VFR flight plan; GRAPHIC PLAN DISPLAY (GPD)− A view obtain an updated weather briefing prior to takeoff; available with EDST that provides a graphic display close an IFR flight plan; or, for Alaska or MEDEVAC of aircraft, traffic, and notification of predicted only, obtain an IFR clearance. Pilots will use four conflicts. Graphic routes for Current Plans and Trial “key clicks” on the VHF radio to contact the Plans are displayed upon controller request. appropriate ATC facility or six “key clicks” to contact (See EN ROUTE DECISION SUPPORT TOOL.) the FSS. The GCO system is intended to be used only GROSS NAVIGATION ERROR (GNE) − A lateral on the ground. deviation of 10 NM or more from the aircraft’s GROUND CONTROLLED APPROACH− A radar cleared route. approach system operated from the ground by air GROUND BASED AUGMENTATION SYSTEM traffic control personnel transmitting instructions to (GBAS)– A ground based GNSS station which the pilot by radio. The approach may be conducted provides local differential corrections, integrity with surveillance radar (ASR) only or with both parameters and approach data via VHF data broadcast surveillance and precision approach radar (PAR). to GNSS users to meet real-time performance Usage of the term “GCA” by pilots is discouraged requirements for CAT I precision approaches. The except when referring to a GCA facility. Pilots should aircraft applies the broadcast data to improve the specifically request a “PAR” approach when a accuracy and integrity of its GNSS signals and precision radar approach is desired or request an computes the deviations to the selected approach. A “ASR” or “surveillance” approach when a nonpreci- single ground station can serve multiple runway ends sion radar approach is desired. up to an approximate radius of 23 NM. (See RADAR APPROACH.)

PCG G−2 6/17/21 Pilot/Controller Glossary

GROUND DELAY PROGRAM (GDP)− A traffic requires aircraft that meet a specific criteria to remain management process administered by the ATCSCC, on the ground. The criteria may be airport specific, when aircraft are held on the ground. The purpose of airspace specific, or equipment specific; for example, the program is to support the TM mission and limit all departures to San Francisco, or all departures airborne holding. It is a flexible program and may be entering Yorktown sector, or all Category I and II implemented in various forms depending upon the aircraft going to Charlotte. GSs normally occur with needs of the AT system. Ground delay programs little or no warning. provide for equitable assignment of delays to all system users. GROUND VISIBILITY− (See VISIBILITY.) GROUND SPEED− The speed of an aircraft relative to the surface of the earth. GS− GROUND STOP (GS)− The GS is a process that (See GROUND STOP.)

PCG G−3

6/17/21 Pilot/Controller Glossary H

HAA− is published on instrument approach charts in (See HEIGHT ABOVE AIRPORT.) conjunction with all straight-in minimums. (See DECISION HEIGHT.) HAL− (See MINIMUM DESCENT ALTITUDE.) (See HEIGHT ABOVE LANDING.) HELICOPTER− A heavier-than-air aircraft sup- HANDOFF− An action taken to transfer the radar ported in flight chiefly by the reactions of the air on identification of an aircraft from one controller to one or more power-driven rotors on substantially another if the aircraft will enter the receiving vertical axes. controller’s airspace and radio communications with HELIPAD− A small, designated area, usually with a the aircraft will be transferred. prepared surface, on a heliport, airport, landing/take- HAT− off area, apron/ramp, or movement area used for (See HEIGHT ABOVE TOUCHDOWN.) takeoff, landing, or parking of helicopters. HAVE NUMBERS− Used by pilots to inform ATC HELIPORT− An area of land, water, or structure used that they have received runway, wind, and altimeter or intended to be used for the landing and takeoff of information only. helicopters and includes its buildings and facilities if any.

HAZARDOUS WEATHER INFORMATION− HELIPORT REFERENCE POINT (HRP)− The Summary of significant meteorological information geographic center of a heliport. (SIGMET/WS), convective significant meteorological information (convective SIGMET/WST), urgent HERTZ− The standard radio equivalent of frequency pilot weather reports (urgent PIREP/UUA), center in cycles per second of an electromagnetic wave. weather advisories (CWA), airmen’s meteorological Kilohertz (kHz) is a frequency of one thousand cycles information (AIRMET/WA) and any other weather per second. Megahertz (MHz) is a frequency of one such as isolated thunderstorms that are rapidly million cycles per second. developing and increasing in intensity, or low HF− ceilings and visibilities that are becoming wide- (See HIGH FREQUENCY.) spread which is considered significant and are not included in a current hazardous weather advisory. HF COMMUNICATIONS− (See HIGH FREQUENCY COMMUNICATIONS.) HEAVY (AIRCRAFT)− (See AIRCRAFT CLASSES.) HIGH FREQUENCY− The frequency band between 3 and 30 MHz. HEIGHT ABOVE AIRPORT (HAA)− The height of (See HIGH FREQUENCY COMMUNICATIONS.) the Minimum Descent Altitude above the published HIGH FREQUENCY COMMUNICATIONS− High airport elevation. This is published in conjunction radio frequencies (HF) between 3 and 30 MHz used with circling minimums. for air-to-ground voice communication in overseas (See MINIMUM DESCENT ALTITUDE.) operations. HEIGHT ABOVE LANDING (HAL)− The height HIGH SPEED EXIT− above a designated helicopter landing area used for (See HIGH SPEED TAXIWAY.) helicopter instrument approach procedures. (Refer to 14 CFR Part 97.) HIGH SPEED TAXIWAY− A long radius taxiway designed and provided with lighting or marking to HEIGHT ABOVE TOUCHDOWN (HAT)− The define the path of aircraft, traveling at high speed (up height of the Decision Height or Minimum Descent to 60 knots), from the runway center to a point on the Altitude above the highest runway elevation in the center of a taxiway. Also referred to as long radius touchdown zone (first 3,000 feet of the runway). HAT exit or turn-off taxiway. The high speed taxiway is

PCG H−1 Pilot/Controller Glossary 6/17/21

designed to expedite aircraft turning off the runway HOLDING POINT [ICAO]− A specified location, after landing, thus reducing runway occupancy time. identified by visual or other means, in the vicinity of which the position of an aircraft in flight is HIGH SPEED TURNOFF− maintained in accordance with air traffic control (See HIGH SPEED TAXIWAY.) clearances. HIGH UPDATE RATE SURVEILLANCE– A HOLDING PROCEDURE− surveillance system that provides a sensor update rate (See HOLD PROCEDURE.) of less than 4.8 seconds. HOLD-SHORT POINT− A point on the runway beyond which a landing aircraft with a LAHSO HOLD FOR RELEASE− Used by ATC to delay an clearance is not authorized to proceed. This point aircraft for traffic management reasons; i.e., weather, may be located prior to an intersecting runway, traffic volume, etc. Hold for release instructions taxiway, predetermined point, or approach/departure (including departure delay information) are used to flight path. inform a pilot or a controller (either directly or through an authorized relay) that an IFR departure HOLD-SHORT POSITION LIGHTS− Flashing clearance is not valid until a release time or additional in-pavement white lights located at specified instructions have been received. hold-short points. (See ICAO term HOLDING POINT.) HOLD-SHORT POSITION MARKING− The painted runway marking located at the hold-short HOLD−IN−LIEU OF PROCEDURE TURN− A point on all LAHSO runways. hold−in−lieu of procedure turn shall be established over a final or intermediate fix when an approach can HOLD-SHORT POSITION SIGNS− Red and white be made from a properly aligned holding pattern. The holding position signs located alongside the hold−in−lieu of procedure turn permits the pilot to hold-short point. align with the final or intermediate segment of the HOMING− Flight toward a NAVAID, without approach and/or descend in the holding pattern to an correcting for wind, by adjusting the aircraft heading altitude that will permit a normal descent to the final to maintain a relative bearing of zero degrees. approach fix altitude. The hold−in−lieu of procedure (See BEARING.) turn is a required maneuver (the same as a procedure (See ICAO term HOMING.) turn) unless the aircraft is being radar vectored to the HOMING [ICAO]− The procedure of using the final approach course, when “NoPT” is shown on the direction-finding equipment of one radio station with approach chart, or when the pilot requests or the the emission of another radio station, where at least controller advises the pilot to make a “straight−in” one of the stations is mobile, and whereby the mobile approach. station proceeds continuously towards the other station. HOLD PROCEDURE− A predetermined maneuver which keeps aircraft within a specified airspace while HOVER CHECK− Used to describe when a awaiting further clearance from air traffic control. helicopter/VTOL aircraft requires a stabilized hover Also used during ground operations to keep aircraft to conduct a performance/power check prior to hover within a specified area or at a specified point while taxi, air taxi, or takeoff. Altitude of the hover will awaiting further clearance from air traffic control. vary based on the purpose of the check. (See HOLDING FIX.) HOVER TAXI− Used to describe a helicopter/VTOL (Refer to AIM.) aircraft movement conducted above the surface and in ground effect at airspeeds less than approximately HOLDING FIX− A specified fix identifiable to a 20 knots. The actual height may vary, and some pilot by NAVAIDs or visual reference to the ground helicopters may require hover taxi above 25 feet AGL used as a reference point in establishing and to reduce ground effect turbulence or provide maintaining the position of an aircraft while holding. clearance for cargo slingloads. (See FIX.) (See AIR TAXI.) (See VISUAL HOLDING.) (See HOVER CHECK.) (Refer to AIM.) (Refer to AIM.)

PCG H−2 6/17/21 Pilot/Controller Glossary

HOW DO YOU HEAR ME?− A question relating to the quality of the transmission or to determine how well the transmission is being received. HZ− (See HERTZ.)

PCG H−3

6/17/21 Pilot/Controller Glossary I

I SAY AGAIN− The message will be repeated. exiting the icing conditions before they become worse. IAF− (See INITIAL APPROACH FIX.) b. Light− The rate of ice accumulation requires occasional cycling of manual deicing systems to IAP− minimize ice accretions on the airframe. A (See INSTRUMENT APPROACH representative accretion rate for reference purposes is PROCEDURE.) ¼ inch to 1 inch (0.6 to 2.5 cm) per hour on the IAWP− Initial Approach Waypoint unprotected part of the outer wing. The pilot should consider exiting the icing condition.

ICAO− c. Moderate− The rate of ice accumulation (See ICAO Term INTERNATIONAL CIVIL requires frequent cycling of manual deicing systems AVIATION ORGANIZATION.) to minimize ice accretions on the airframe. A ICAO 3LD− representative accretion rate for reference purposes is (See ICAO Term ICAO Three−Letter Designator) 1 to 3 inches (2.5 to 7.5 cm) per hour on the unprotected part of the outer wing. The pilot should ICAO Three−Letter Designator (3LD)− An ICAO consider exiting the icing condition as soon as 3LD is an exclusive designator that, when used possible. together with a flight number, becomes the aircraft call sign and provides distinct aircraft identification d. Severe− The rate of ice accumulation is such to air traffic control (ATC). ICAO approves 3LDs to that ice protection systems fail to remove the enhance the safety and security of the air traffic accumulation of ice and ice accumulates in locations system. An ICAO 3LD may be assigned to a not normally prone to icing, such as areas aft of company, agency, or organization and is used instead protected surfaces and any other areas identified by of the aircraft registration number for ATC the manufacturer. A representative accretion rate for operational and security purposes. An ICAO 3LD is reference purposes is more than 3 inches (7.5 cm) per also used for aircraft identification in the flight plan hour on the unprotected part of the outer wing. By and associated messages and can be used for regulation, immediate exit is required. domestic and international flights. A telephony Note: associated with an ICAO 3LD is used for radio Severe icing is aircraft dependent, as are the other categories of icing intensity. Severe icing may communication. occur at any ice accumulation rate when the icing ICING− The accumulation of airframe ice. rate or ice accumulations exceed the tolerance of the aircraft. Types of icing are: IDENT− A request for a pilot to activate the aircraft a. Rime Ice− Rough, milky, opaque ice formed by transponder identification feature. This will help the the instantaneous freezing of small supercooled controller to confirm an aircraft identity or to identify water droplets. an aircraft. b. Clear Ice− A glossy, clear, or translucent ice (Refer to AIM.) formed by the relatively slow freezing of large supercooled water droplets. IDENT FEATURE− The special feature in the Air Traffic Control Radar Beacon System (ATCRBS) c. Mixed− A mixture of clear ice and rime ice. equipment. It is used to immediately distinguish one Intensity of icing: displayed beacon target from other beacon targets. a. Trace− Ice becomes noticeable. The rate of (See IDENT.) accumulation is slightly greater than the rate of IDENTIFICATION [ICAO]− The situation which sublimation. A representative accretion rate for exists when the position indication of a particular reference purposes is less than ¼ inch (6 mm) per aircraft is seen on a situation display and positively hour on the outer wing. The pilot should consider identified.

PCG I−1 Pilot/Controller Glossary 6/17/21

IF− facilities available, pilots should advise ATC of any (See INTERMEDIATE FIX.) departure limitations. Controllers may query a pilot to determine acceptable departure directions, turns, IF NO TRANSMISSION RECEIVED FOR or headings after takeoff. Pilots should be familiar (TIME)− Used by ATC in radar approaches to prefix with the departure procedures and must assure that procedures which should be followed by the pilot in their aircraft can meet or exceed any specified climb event of lost communications. gradients. (See LOST COMMUNICATIONS.) IF/IAWP− Intermediate Fix/Initial Approach Way- IFR− point. The waypoint where the final approach course (See INSTRUMENT FLIGHT RULES.) of a T approach meets the crossbar of the T. When IFR AIRCRAFT− An aircraft conducting flight in designated (in conjunction with a TAA) this accordance with instrument flight rules. waypoint will be used as an IAWP when approaching the airport from certain directions, and as an IFWP IFR CONDITIONS− Weather conditions below the when beginning the approach from another IAWP. minimum for flight under visual flight rules. (See INSTRUMENT METEOROLOGICAL IFWP− Intermediate Fix Waypoint CONDITIONS.) ILS− IFR DEPARTURE PROCEDURE− (See INSTRUMENT LANDING SYSTEM.) (See IFR TAKEOFF MINIMUMS AND ILS CATEGORIES− 1. Category I. An ILS approach DEPARTURE PROCEDURES.) procedure which provides for approach to a height (Refer to AIM.) above touchdown of not less than 200 feet and with IFR FLIGHT− runway visual range of not less than 1,800 feet.− (See IFR AIRCRAFT.) 2. Special Authorization Category I. An ILS approach procedure which provides for approach to IFR LANDING MINIMUMS− a height above touchdown of not less than 150 feet (See LANDING MINIMUMS.) and with runway visual range of not less than 1,400 IFR MILITARY TRAINING ROUTES (IR)− Routes feet, HUD to DH. 3. Category II. An ILS approach used by the Department of Defense and associated procedure which provides for approach to a height Reserve and Air Guard units for the purpose of above touchdown of not less than 100 feet and with conducting low-altitude navigation and tactical runway visual range of not less than 1,200 feet (with training in both IFR and VFR weather conditions autoland or HUD to touchdown and noted on below 10,000 feet MSL at airspeeds in excess of 250 authorization, RVR 1,000 feet).− 4. Special knots IAS. Authorization Category II with Reduced Lighting. An ILS approach procedure which provides for IFR TAKEOFF MINIMUMS AND DEPARTURE approach to a height above touchdown of not less PROCEDURES− Title 14 Code of Federal than 100 feet and with runway visual range of not less Regulations Part 91, prescribes standard takeoff rules than 1,200 feet with autoland or HUD to touchdown for certain civil users. At some airports, obstructions and noted on authorization (no touchdown zone and or other factors require the establishment of centerline lighting are required).− 5. Category III: nonstandard takeoff minimums, departure proce- a. IIIA.−An ILS approach procedure which dures, or both to assist pilots in avoiding obstacles provides for approach without a decision height during climb to the minimum en route altitude. Those minimum and with runway visual range of not less airports are listed in FAA/DOD Instrument Approach than 700 feet. Procedures (IAPs) Charts under a section entitled “IFR Takeoff Minimums and Departure Procedures.” b. IIIB.−An ILS approach procedure which The FAA/DOD IAP chart legend illustrates the provides for approach without a decision height symbol used to alert the pilot to nonstandard takeoff minimum and with runway visual range of not less minimums and departure procedures. When depart- than 150 feet. ing IFR from such airports or from any airports where c. IIIC.−An ILS approach procedure which there are no departure procedures, DPs, or ATC provides for approach without a decision height

PCG I−2 6/17/21 Pilot/Controller Glossary

minimum and without runway visual range INLAND NAVIGATION FACILITY− A navigation minimum. aid on a North American Route at which the common route and/or the noncommon route begins or ends. IM− (See INNER MARKER.) INNER MARKER− A marker beacon used with an ILS (CAT II) precision approach located between the IMC− middle marker and the end of the ILS runway, (See INSTRUMENT METEOROLOGICAL transmitting a radiation pattern keyed at six dots per CONDITIONS.) second and indicating to the pilot, both aurally and IMMEDIATELY− Used by ATC or pilots when such visually, that he/she is at the designated decision action compliance is required to avoid an imminent height (DH), normally 100 feet above the touchdown situation. zone elevation, on the ILS CAT II approach. It also INCERFA (Uncertainty Phase) [ICAO]− A situation marks progress during a CAT III approach. wherein uncertainty exists as to the safety of an (See INSTRUMENT LANDING SYSTEM.) aircraft and its occupants. (Refer to AIM.) INCREASED SEPARATION REQUIRED (ISR)– INNER MARKER BEACON− Indicates the confidence level of the track requires 5 (See INNER MARKER.) ½ NM separation. 3 NM separation, 1 NM INREQ− separation, and target resolution cannot be used. (See INFORMATION REQUEST.)

INCREASE SPEED TO (SPEED)− INS− (See SPEED ADJUSTMENT.) (See INERTIAL NAVIGATION SYSTEM.) INERTIAL NAVIGATION SYSTEM (INS)− An INSTRUMENT APPROACH− RNAV system which is a form of self-contained navigation. (See INSTRUMENT APPROACH PROCEDURE.) (See Area Navigation/RNAV.) INSTRUMENT APPROACH OPERATIONS INFLIGHT REFUELING− [ICAO]− An approach and landing using instruments (See AERIAL REFUELING.) for navigation guidance based on an instrument INFLIGHT WEATHER ADVISORY− approach procedure. There are two methods for (See WEATHER ADVISORY.) executing instrument approach operations: INFORMATION REQUEST (INREQ)− A request a. A two−dimensional (2D) instrument approach originated by an FSS for information concerning an operation, using lateral navigation guidance only; overdue VFR aircraft. and b. A three−dimensional (3D) instrument approach INITIAL APPROACH FIX (IAF)− The fixes operation, using both lateral and vertical navigation depicted on instrument approach procedure charts guidance. that identify the beginning of the initial approach segment(s). Note: Lateral and vertical navigation guidance refers to the guidance provided either by: (See FIX.) a) a ground−based radio navigation aid; or (See SEGMENTS OF AN INSTRUMENT b) computer−generated navigation data from APPROACH PROCEDURE.) ground−based, space−based, self−contained INITIAL APPROACH SEGMENT− navigation aids or a combination of these. (See SEGMENTS OF AN INSTRUMENT (See ICAO term INSTRUMENT APPROACH APPROACH PROCEDURE.) PROCEDURE.) INITIAL APPROACH SEGMENT [ICAO]− That INSTRUMENT APPROACH PROCEDURE− A segment of an instrument approach procedure series of predetermined maneuvers for the orderly between the initial approach fix and the intermediate transfer of an aircraft under instrument flight approach fix or, where applicable, the final approach conditions from the beginning of the initial approach fix or point. to a landing or to a point from which a landing may

PCG I−3 Pilot/Controller Glossary 6/17/21

be made visually. It is prescribed and approved for a INSTRUMENT DEPARTURE PROCEDURE (DP) specific airport by competent authority. CHARTS− (See SEGMENTS OF AN INSTRUMENT (See AERONAUTICAL CHART.) APPROACH PROCEDURE.) INSTRUMENT FLIGHT RULES (IFR)− Rules (Refer to 14 CFR Part 91.) governing the procedures for conducting instrument (Refer to AIM.) flight. Also a term used by pilots and controllers to indicate type of flight plan. a. U.S. civil standard instrument approach procedures are approved by the FAA as prescribed (See INSTRUMENT METEOROLOGICAL CONDITIONS.) under 14 CFR Part 97 and are available for public (See VISUAL FLIGHT RULES.) use. (See VISUAL METEOROLOGICAL b. U.S. military standard instrument approach CONDITIONS.) procedures are approved and published by the (See ICAO term INSTRUMENT FLIGHT Department of Defense. RULES.) (Refer to AIM.) c. Special instrument approach procedures are approved by the FAA for individual operators but are INSTRUMENT FLIGHT RULES [ICAO]− A set of not published in 14 CFR Part 97 for public use. rules governing the conduct of flight under instrument meteorological conditions. (See ICAO term INSTRUMENT APPROACH PROCEDURE.) INSTRUMENT LANDING SYSTEM (ILS)− A precision instrument approach system which normal- INSTRUMENT APPROACH PROCEDURE ly consists of the following electronic components [ICAO]− A series of predetermined maneuvers by and visual aids: reference to flight instruments with specified a. Localizer. protection from obstacles from the initial approach (See LOCALIZER.) fix, or where applicable, from the beginning of a b. Glideslope. defined arrival route to a point from which a landing (See GLIDESLOPE.) can be completed and thereafter, if a landing is not c. Outer Marker. completed, to a position at which holding or en route obstacle clearance criteria apply. (See OUTER MARKER.) d. Middle Marker. (See ICAO term INSTRUMENT APPROACH OPERATIONS) (See MIDDLE MARKER.) e. Approach Lights. INSTRUMENT APPROACH PROCEDURE (See AIRPORT LIGHTING.) CHARTS− (Refer to 14 CFR Part 91.) (See AERONAUTICAL CHART.) (Refer to AIM.) INSTRUMENT METEOROLOGICAL CONDI- INSTRUMENT DEPARTURE PROCEDURE TIONS (IMC)− Meteorological conditions expressed (DP)− A preplanned instrument flight rule (IFR) in terms of visibility, distance from cloud, and ceiling departure procedure published for pilot use, in less than the minima specified for visual meteorolog- graphic or textual format, that provides obstruction ical conditions. clearance from the terminal area to the appropriate en (See INSTRUMENT FLIGHT RULES.) route structure. There are two types of DP, Obstacle (See VISUAL FLIGHT RULES.) Departure Procedure (ODP), printed either textually (See VISUAL METEOROLOGICAL or graphically, and, Standard Instrument Departure CONDITIONS.) (SID), which is always printed graphically. INSTRUMENT RUNWAY− A runway equipped (See IFR TAKEOFF MINIMUMS AND with electronic and visual navigation aids for which DEPARTURE PROCEDURES.) a precision or nonprecision approach procedure (See OBSTACLE DEPARTURE PROCEDURES.) having straight-in landing minimums has been (See STANDARD INSTRUMENT DEPARTURES.) approved. (Refer to AIM.) (See ICAO term INSTRUMENT RUNWAY.)

PCG I−4 6/17/21 Pilot/Controller Glossary

INSTRUMENT RUNWAY [ICAO]− One of the procedure and the final approach fix or point, as following types of runways intended for the appropriate. operation of aircraft using instrument approach INTERMEDIATE FIX− The fix that identifies the procedures: beginning of the intermediate approach segment of an a. Nonprecision Approach Runway− An instru- instrument approach procedure. The fix is not ment runway served by visual aids and a nonvisual normally identified on the instrument approach chart aid providing at least directional guidance adequate as an intermediate fix (IF). for a straight-in approach. (See SEGMENTS OF AN INSTRUMENT b. Precision Approach Runway, Category I− An APPROACH PROCEDURE.) instrument runway served by ILS and visual aids INTERMEDIATE LANDING− On the rare occasion intended for operations down to 60 m (200 feet) that this option is requested, it should be approved. decision height and down to an RVR of the order of The departure center, however, must advise the 800 m. ATCSCC so that the appropriate delay is carried over c. Precision Approach Runway, Category II− An and assigned at the intermediate airport. An instrument runway served by ILS and visual aids intermediate landing airport within the arrival center intended for operations down to 30 m (100 feet) will not be accepted without coordination with and decision height and down to an RVR of the order of the approval of the ATCSCC. 400 m. INTERNATIONAL AIRPORT− Relating to interna- d. Precision Approach Runway, Category III− An tional flight, it means: instrument runway served by ILS to and along the a. An airport of entry which has been designated surface of the runway and: by the Secretary of Treasury or Commissioner of 1. Intended for operations down to an RVR of Customs as an international airport for customs the order of 200 m (no decision height being service. applicable) using visual aids during the final phase of b. A landing rights airport at which specific landing; permission to land must be obtained from customs 2. Intended for operations down to an RVR of authorities in advance of contemplated use. the order of 50 m (no decision height being c. Airports designated under the Convention on applicable) using visual aids for taxiing; International Civil Aviation as an airport for use by 3. Intended for operations without reliance on international commercial air transport and/or interna- visual reference for landing or taxiing. tional general aviation. Note 1: See Annex 10 Volume I, Part I, Chapter 3, (See ICAO term INTERNATIONAL AIRPORT.) for related ILS specifications. (Refer to Chart Supplement U.S.) Note 2: Visual aids need not necessarily be INTERNATIONAL AIRPORT [ICAO]− Any airport matched to the scale of nonvisual aids provided. designated by the Contracting State in whose The criterion for the selection of visual aids is the territory it is situated as an airport of entry and conditions in which operations are intended to be conducted. departure for international air traffic, where the formalities incident to customs, immigration, public INTEGRITY− The ability of a system to provide health, animal and plant quarantine and similar timely warnings to users when the system should not procedures are carried out. be used for navigation. INTERNATIONAL CIVIL AVIATION ORGA- INTERMEDIATE APPROACH SEGMENT− NIZATION [ICAO]− A specialized agency of the (See SEGMENTS OF AN INSTRUMENT United Nations whose objective is to develop the APPROACH PROCEDURE.) principles and techniques of international air INTERMEDIATE APPROACH SEGMENT navigation and to foster planning and development of [ICAO]− That segment of an instrument approach international civil air transport. procedure between either the intermediate approach INTERNATIONAL NOTICE− A notice containing fix and the final approach fix or point, or between the flight prohibitions, potential hostile situations, or end of a reversal, race track or dead reckoning track other international/foreign oceanic airspace matters.

PCG I−5 Pilot/Controller Glossary 6/17/21

These notices can be found on the International a. A point defined by any combination of courses, Notices website. radials, or bearings of two or more navigational aids. INTERROGATOR− The ground-based surveillance b. Used to describe the point where two runways, radar beacon transmitter-receiver, which normally a runway and a taxiway, or two taxiways cross or scans in synchronism with a primary radar, meet. transmitting discrete radio signals which repetitious- INTERSECTION DEPARTURE− A departure from ly request all transponders on the mode being used to any runway intersection except the end of the runway. reply. The replies received are mixed with the (See INTERSECTION.) primary radar returns and displayed on the same plan position indicator (radar scope). Also, applied to the INTERSECTION TAKEOFF− airborne element of the TACAN/DME system. (See INTERSECTION DEPARTURE.) (See TRANSPONDER.) IR− (Refer to AIM.) (See IFR MILITARY TRAINING ROUTES.) INTERSECTING RUNWAYS− Two or more IRREGULAR SURFACE− A surface that is open for runways which cross or meet within their lengths. use but not per regulations. (See INTERSECTION.) ISR− INTERSECTION− (See INCREASED SEPARATION REQUIRED.)

PCG I−6 6/17/21 Pilot/Controller Glossary J

JAMMING− Denotes emissions that do not mimic JET STREAM− A migrating stream of high-speed Global Navigation Satellite System (GNSS) signals winds present at high altitudes. (e.g., GPS and WAAS), but rather interfere with the civil receiver’s ability to acquire and track GNSS JETTISONING OF EXTERNAL STORES− Air- signals. Jamming can result in denial of GNSS borne release of external stores; e.g., tiptanks, navigation, positioning, timing and aircraft depen- ordnance. dent functions. (See FUEL DUMPING.) JET BLAST− The rapid air movement produced by (Refer to 14 CFR Part 91.) exhaust from jet engines.

JET ROUTE− A route designed to serve aircraft JOINT USE RESTRICTED AREA− operations from 18,000 feet MSL up to and including flight level 450. The routes are referred to as “J” (See RESTRICTED AREA.) routes with numbering to identify the designated route; e.g., J105. JUMP ZONE− The airspace directly associated with (See Class A AIRSPACE.) a Drop Zone. Vertical and horizontal limits may be (Refer to 14 CFR Part 71.) locally defined.

PCG J−1

6/17/21 Pilot/Controller Glossary K

KNOWN TRAFFIC− With respect to ATC clearances, means aircraft whose altitude, position, and intentions are known to ATC.

PCG K−1

6/17/21 Pilot/Controller Glossary L

LAA− LANDING DISTANCE AVAILABLE (LDA)− The (See LOCAL AIRPORT ADVISORY.) runway length declared available and suitable for a landing airplane. LAHSO− An acronym for “Land and Hold Short (See ICAO term LANDING DISTANCE Operation.” These operations include landing and AVAILABLE.) holding short of an intersecting runway, a taxiway, a predetermined point, or an approach/departure LANDING DISTANCE AVAILABLE [ICAO]− The flightpath. length of runway which is declared available and suitable for the ground run of an aeroplane landing. LAHSO-DRY− Land and hold short operations on LANDING MINIMUMS− The minimum visibility runways that are dry. prescribed for landing a civil aircraft while using an LAHSO-WET− Land and hold short operations on instrument approach procedure. The minimum runways that are wet (but not contaminated). applies with other limitations set forth in 14 CFR Part 91 with respect to the Minimum Descent LAND AND HOLD SHORT OPERATIONS− Altitude (MDA) or Decision Height (DH) prescribed Operations which include simultaneous takeoffs and in the instrument approach procedures as follows: landings and/or simultaneous landings when a landing aircraft is able and is instructed by the a. Straight-in landing minimums. A statement of controller to hold-short of the intersecting runway/ MDA and visibility, or DH and visibility, required for taxiway or designated hold-short point. Pilots are a straight-in landing on a specified runway, or expected to promptly inform the controller if the hold b. Circling minimums. A statement of MDA and short clearance cannot be accepted. visibility required for the circle-to-land maneuver. (See PARALLEL RUNWAYS.) Note: Descent below the MDA or DH must meet the (Refer to AIM.) conditions stated in 14 CFR Section 91.175. (See CIRCLE-TO-LAND MANEUVER.) LAND−BASED AIR DEFENSE IDENTIFICA- (See DECISION HEIGHT.) TION ZONE (ADIZ)− An ADIZ over U.S. (See INSTRUMENT APPROACH metropolitan areas, which is activated and deactivat- PROCEDURE.) ed as needed, with dimensions, activation dates, and (See MINIMUM DESCENT ALTITUDE.) other relevant information disseminated via NO- (See STRAIGHT-IN LANDING.) TAM. (See VISIBILITY.) (See AIR DEFENSE IDENTIFICATION ZONE.) (Refer to 14 CFR Part 91.) LANDING AREA− Any locality either on land, LANDING ROLL− The distance from the point of water, or structures, including airports/heliports and touchdown to the point where the aircraft can be intermediate landing fields, which is used, or brought to a stop or exit the runway. intended to be used, for the landing and takeoff of LANDING SEQUENCE− The order in which aircraft whether or not facilities are provided for the aircraft are positioned for landing. shelter, servicing, or for receiving or discharging (See APPROACH SEQUENCE.) passengers or cargo. (See ICAO term LANDING AREA.) LAST ASSIGNED ALTITUDE− The last altitude/ flight level assigned by ATC and acknowledged by LANDING AREA [ICAO]− That part of a movement the pilot. area intended for the landing or take-off of aircraft. (See MAINTAIN.) LANDING DIRECTION INDICATOR− A device (Refer to 14 CFR Part 91.) which visually indicates the direction in which LATERAL NAVIGATION (LNAV)– A function of landings and takeoffs should be made. area navigation (RNAV) equipment which calculates, (See TETRAHEDRON.) displays, and provides lateral guidance to a profile or (Refer to AIM.) path.

PCG L−1 Pilot/Controller Glossary 6/17/21

LATERAL SEPARATION− The lateral spacing of LINE UP AND WAIT (LUAW)− Used by ATC to aircraft at the same altitude by requiring operation on inform a pilot to taxi onto the departure runway to line different routes or in different geographical locations. up and wait. It is not authorization for takeoff. It is (See SEPARATION.) used when takeoff clearance cannot immediately be issued because of traffic or other reasons. LDA− (See CLEARED FOR TAKEOFF.) (See LOCALIZER TYPE DIRECTIONAL AID.) LOCAL AIRPORT ADVISORY (LAA)− A service (See LANDING DISTANCE AVAILABLE.) available only in Alaska and provided by facilities (See ICAO Term LANDING DISTANCE that are located on the landing airport, have a discrete AVAILABLE.) ground−to−air communication frequency or the tower frequency when the tower is closed, automated LF− weather reporting with voice broadcasting, and a (See LOW FREQUENCY.) continuous ASOS/AWOS data display, other continuous direct reading instruments, or manual LIGHTED AIRPORT− An airport where runway and observations available to the specialist. obstruction lighting is available. (See AIRPORT ADVISORY AREA.) (See AIRPORT LIGHTING.) (Refer to AIM.) LOCAL TRAFFIC− Aircraft operating in the traffic pattern or within sight of the tower, or aircraft known LIGHT GUN− A handheld directional light signaling to be departing or arriving from flight in local practice device which emits a brilliant narrow beam of white, areas, or aircraft executing practice instrument green, or red light as selected by the tower controller. approaches at the airport. The color and type of light transmitted can be used to (See TRAFFIC PATTERN.) approve or disapprove anticipated pilot actions where LOCALIZER− The component of an ILS which radio communication is not available. The light gun provides course guidance to the runway. is used for controlling traffic operating in the vicinity of the airport and on the airport movement area. (See INSTRUMENT LANDING SYSTEM.) (See ICAO term LOCALIZER COURSE.) (Refer to AIM.) (Refer to AIM.) LIGHT-SPORT AIRCRAFT (LSA)− An LOCALIZER COURSE [ICAO]− The locus of FAA-registered aircraft, other than a helicopter or points, in any given horizontal plane, at which the powered-lift, that meets certain weight and DDM (difference in depth of modulation) is zero. performance. Principally it is a single−engine aircraft with a maximum of two seats and weighing no more LOCALIZER OFFSET− An angular offset of the than 1,430 pounds if intended for operation on water, localizer aligned within 3 of the runway alignment. or 1,320 pounds if not. It must be of simple design LOCALIZER TYPE DIRECTIONAL AID (LDA)− (fixed landing gear (except if intended for operations A localizer with an angular offset that exceeds 3 of on water or a glider), piston powered, the runway alignment, used for nonprecision nonpressurized, with a fixed or ground adjustable instrument approaches with utility and accuracy propeller). Performance is also limited to a maximum comparable to a localizer, but which are not part of a airspeed in level flight of not more than 120 knots complete ILS. calibrated airspeed (CAS), have a maximum never-exceed speed of not more than 120 knots CAS (Refer to AIM.) for a glider, and have a maximum stalling speed, LOCALIZER TYPE DIRECTIONAL AID (LDA) without the use of lift-enhancing devices of not more PRECISION RUNWAY MONITOR (PRM) than 45 knots CAS. It may be certificated as either APPROACH− An approach, which includes a Experimental LSA or as a Special LSA aircraft. A glideslope, used in conjunction with an ILS PRM, minimum of a sport pilot certificate is required to RNAV PRM or GLS PRM approach to an adjacent operate light-sport aircraft. runway to conduct Simultaneous Offset Instrument (Refer to 14 CFR Part 1, §1.1.) Approaches (SOIA) to parallel runways whose

PCG L−2 6/17/21 Pilot/Controller Glossary

centerlines are separated by less than 3,000 feet and LOST LINK (LL)− An interruption or loss of the at least 750 feet. NTZ monitoring is required to control link, or when the pilot is unable to effect conduct these approaches. control of the aircraft and, as a result, the UA will (See SIMULTANEOUS OFFSET INSTRUMENT perform a predictable or planned maneuver. Loss of APPROACH (SOIA).) command and control link between the Control (Refer to AIM) Station and the aircraft. There are two types of links: LOCALIZER USABLE DISTANCE− The maxi- a. An uplink which transmits command instruc- mum distance from the localizer transmitter at a tions to the aircraft, and specified altitude, as verified by flight inspection, at b. A downlink which transmits the status of the which reliable course information is continuously aircraft and provides situational awareness to the received. pilot. (Refer to AIM.) LOST LINK PROCEDURE− Preprogrammed or LOCATOR [ICAO]− An LM/MF NDB used as an aid predetermined mitigations to ensure the continued to final approach. safe operation of the UA in the event of a lost link Note: A locator usually has an average radius of (LL). In the event positive link cannot be established, rated coverage of between 18.5 and 46.3 km (10 flight termination must be implemented. and 25 NM). LONG RANGE NAVIGATION− LOW ALTITUDE AIRWAY STRUCTURE− The (See LORAN.) network of airways serving aircraft operations up to but not including 18,000 feet MSL. LONGITUDINAL SEPARATION− The longitudi- (See AIRWAY.) nal spacing of aircraft at the same altitude by a (Refer to AIM.) minimum distance expressed in units of time or miles. LOW ALTITUDE ALERT, CHECK YOUR ALTI- (See SEPARATION.) TUDE IMMEDIATELY− (Refer to AIM.) (See SAFETY ALERT.) LORAN− An electronic navigational system by LOW APPROACH− An approach over an airport or which hyperbolic lines of position are determined by runway following an instrument approach or a VFR measuring the difference in the time of reception of approach including the go-around maneuver where synchronized pulse signals from two fixed transmit- the pilot intentionally does not make contact with the ters. Loran A operates in the 1750-1950 kHz runway. frequency band. Loran C and D operate in the (Refer to AIM.) 100-110 kHz frequency band. In 2010, the U.S. Coast Guard terminated all U.S. LORAN-C transmissions. LOW FREQUENCY (LF)− The frequency band (Refer to AIM.) between 30 and 300 kHz. LOST COMMUNICATIONS− Loss of the ability to (Refer to AIM.) communicate by radio. Aircraft are sometimes LOCALIZER PERFORMANCE WITH VERTI- referred to as NORDO (No Radio). Standard pilot CAL GUIDANCE (LPV)− A type of approach with procedures are specified in 14 CFR Part 91. Radar vertical guidance (APV) based on WAAS, published controllers issue procedures for pilots to follow in the on RNAV (GPS) approach charts. This procedure event of lost communications during a radar approach takes advantage of the precise lateral guidance when weather reports indicate that an aircraft will available from WAAS. The minima is published as a likely encounter IFR weather conditions during the decision altitude (DA). approach. (Refer to 14 CFR Part 91.) LUAW− (Refer to AIM.) (See LINE UP AND WAIT.)

PCG L−3

6/17/21 Pilot/Controller Glossary M

MAA− is real and requires familiarity with the subject. (See MAXIMUM AUTHORIZED ALTITUDE.) Terrorists choose MANPADS because the weapons are low cost, highly mobile, require minimal set−up MACH NUMBER− The ratio of true airspeed to the time, and are easy to use and maintain. Although the speed of sound; e.g., MACH .82, MACH 1.6. weapons have limited range, and their accuracy is (See AIRSPEED.) affected by poor visibility and adverse weather, they MACH TECHNIQUE [ICAO]− Describes a control can be fired from anywhere on land or from boats technique used by air traffic control whereby turbojet where there is unrestricted visibility to the target. aircraft operating successively along suitable routes MANDATORY ALTITUDE− An altitude depicted are cleared to maintain appropriate MACH numbers on an instrument Approach Procedure Chart for a relevant portion of the en route phase of flight. requiring the aircraft to maintain altitude at the The principle objective is to achieve improved depicted value. utilization of the airspace and to ensure that separation between successive aircraft does not MANPADS− decrease below the established minima. (See MAN PORTABLE AIR DEFENSE SYSTEMS.) MAHWP− Missed Approach Holding Waypoint MAP− MAINTAIN− (See MISSED APPROACH POINT.) a. Concerning altitude/flight level, the term MARKER BEACON− An electronic navigation means to remain at the altitude/flight level specified. facility transmitting a 75 MHz vertical fan or The phrase “climb and” or “descend and” normally boneshaped radiation pattern. Marker beacons are precedes “maintain” and the altitude assignment; identified by their modulation frequency and keying e.g., “descend and maintain 5,000.” code, and when received by compatible airborne b. Concerning other ATC instructions, the term is equipment, indicate to the pilot, both aurally and used in its literal sense; e.g., maintain VFR. visually, that he/she is passing over the facility. (See INNER MARKER.) MAINTENANCE PLANNING FRICTION (See MIDDLE MARKER.) LEVEL− The friction level specified in (See OUTER MARKER.) AC 150/5320-12, Measurement, Construction, and (Refer to AIM.) Maintenance of Skid Resistant Airport Pavement Surfaces, which represents the friction value below MARSA− which the runway pavement surface remains (See MILITARY AUTHORITY ASSUMES acceptable for any category or class of aircraft RESPONSIBILITY FOR SEPARATION OF operations but which is beginning to show signs of AIRCRAFT.) deterioration. This value will vary depending on the MAWP− Missed Approach Waypoint particular friction measurement equipment used. MAXIMUM AUTHORIZED ALTITUDE− A pub- MAKE SHORT APPROACH− Used by ATC to lished altitude representing the maximum usable inform a pilot to alter his/her traffic pattern so as to altitude or flight level for an airspace structure or make a short final approach. route segment. It is the highest altitude on a Federal (See TRAFFIC PATTERN.) airway, jet route, area navigation low or high route, or other direct route for which an MEA is designated MAN PORTABLE AIR DEFENSE SYSTEMS in 14 CFR Part 95 at which adequate reception of (MANPADS)− MANPADS are lightweight, navigation aid signals is assured. shoulder−launched, missile systems used to bring down aircraft and create mass casualties. The MAYDAY− The international radiotelephony distress potential for MANPADS use against airborne aircraft signal. When repeated three times, it indicates

PCG M−1 Pilot/Controller Glossary 6/17/21

imminent and grave danger and that immediate METERING AIRPORTS− Airports adapted for assistance is requested. metering and for which optimum flight paths are (See PAN-PAN.) defined. A maximum of 15 airports may be adapted. (Refer to AIM.) METERING FIX− A fix along an established route MCA− from over which aircraft will be metered prior to (See MINIMUM CROSSING ALTITUDE.) entering terminal airspace. Normally, this fix should be established at a distance from the airport which MDA− will facilitate a profile descent 10,000 feet above (See MINIMUM DESCENT ALTITUDE.) airport elevation (AAE) or above. MEA− METERING POSITION(S)− Adapted PVDs/ (See MINIMUM EN ROUTE IFR ALTITUDE.) MDMs and associated “D” positions eligible for MEARTS− display of a metering position list. A maximum of (See MICRO-EN ROUTE AUTOMATED RADAR four PVDs/MDMs may be adapted. TRACKING SYSTEM.) METERING POSITION LIST− An ordered list of METEOROLOGICAL IMPACT STATEMENT− data on arrivals for a selected metering airport An unscheduled planning forecast describing displayed on a metering position PVD/MDM. conditions expected to begin within 4 to 12 hours

which may impact the flow of air traffic in a specific MFT− center’s (ARTCC) area. (See METER FIX TIME/SLOT TIME.) METER FIX ARC− A semicircle, equidistant from MHA− a meter fix, usually in low altitude relatively close to (See MINIMUM HOLDING ALTITUDE.) the meter fix, used to help CTAS/ERAM calculate a MIA− meter time, and determine appropriate sector meter (See MINIMUM IFR ALTITUDES.) list assignments for aircraft not on an established arrival route or assigned a meter fix. MICROBURST− A small downburst with outbursts of damaging winds extending 2.5 miles or less. In METER FIX TIME/SLOT TIME (MFT)− A spite of its small horizontal scale, an intense calculated time to depart the meter fix in order to microburst could induce wind speeds as high as 150 cross the vertex at the ACLT. This time reflects knots descent speed adjustment and any applicable time (Refer to AIM.) that must be absorbed prior to crossing the meter fix. MICRO-EN ROUTE AUTOMATED RADAR METER LIST− TRACKING SYSTEM (MEARTS)− An automated (See ARRIVAL SECTOR ADVISORY LIST.) radar and radar beacon tracking system capable of METER LIST DISPLAY INTERVAL− A dynamic employing both short-range (ASR) and long-range parameter which controls the number of minutes (ARSR) radars. This microcomputer driven system prior to the flight plan calculated time of arrival at the provides improved tracking, continuous data record- meter fix for each aircraft, at which time the TCLT is ing, and use of full digital radar displays. frozen and becomes an ACLT; i.e., the VTA is MID RVR− updated and consequently the TCLT modified as (See VISIBILITY.) appropriate until frozen at which time updating is suspended and an ACLT is assigned. When frozen, MIDDLE COMPASS LOCATOR− the flight entry is inserted into the arrival sector’s (See COMPASS LOCATOR.) meter list for display on the sector PVD/MDM. MIDDLE MARKER− A marker beacon that defines MLDI is used if filed true airspeed is less than or a point along the glideslope of an ILS normally equal to freeze speed parameters (FSPD). located at or near the point of decision height (ILS METERING− A method of time-regulating arrival Category I). It is keyed to transmit alternate dots and traffic flow into a terminal area so as not to exceed a dashes, with the alternate dots and dashes keyed at the predetermined terminal acceptance rate. rate of 95 dot/dash combinations per minute on a

PCG M−2 6/17/21 Pilot/Controller Glossary

1300 Hz tone, which is received aurally and visually which assures acceptable navigational signal cover- by compatible airborne equipment. age and meets obstacle clearance requirements (See INSTRUMENT LANDING SYSTEM.) between those fixes. The MEA prescribed for a (See MARKER BEACON.) Federal airway or segment thereof, area navigation (Refer to AIM.) low or high route, or other direct route applies to the entire width of the airway, segment, or route between MILES-IN-TRAIL− A specified distance between the radio fixes defining the airway, segment, or route. aircraft, normally, in the same stratum associated (Refer to 14 CFR Part 91.) with the same destination or route of flight. (Refer to 14 CFR Part 95.) MILITARY AUTHORITY ASSUMES RESPONSI- (Refer to AIM.) BILITY FOR SEPARATION OF AIRCRAFT (MARSA)− A condition whereby the military MINIMUM FRICTION LEVEL− The friction level services involved assume responsibility for separa- specified in AC 150/5320-12, Measurement, Con- tion between participating military aircraft in the struction, and Maintenance of Skid Resistant Airport ATC system. It is used only for required IFR Pavement Surfaces, that represents the minimum operations which are specified in letters of agreement recommended wet pavement surface friction value or other appropriate FAA or military documents. for any turbojet aircraft engaged in LAHSO. This value will vary with the particular friction MILITARY LANDING ZONE− A landing strip used measurement equipment used. exclusively by the military for training. A military landing zone does not carry a runway designation. MINIMUM FUEL− Indicates that an aircraft’s fuel MILITARY OPERATIONS AREA− supply has reached a state where, upon reaching the destination, it can accept little or no delay. This is not (See SPECIAL USE AIRSPACE.) an emergency situation but merely indicates an MILITARY TRAINING ROUTES− Airspace of emergency situation is possible should any undue defined vertical and lateral dimensions established delay occur. for the conduct of military flight training at airspeeds (Refer to AIM.) in excess of 250 knots IAS. (See IFR MILITARY TRAINING ROUTES.) MINIMUM HOLDING ALTITUDE− The lowest (See VFR MILITARY TRAINING ROUTES.) altitude prescribed for a holding pattern which assures navigational signal coverage, communica- MINIMA− tions, and meets obstacle clearance requirements. (See MINIMUMS.) MINIMUM IFR ALTITUDES (MIA)− Minimum MINIMUM CROSSING ALTITUDE (MCA)− The altitudes for IFR operations as prescribed in 14 CFR lowest altitude at certain fixes at which an aircraft Part 91. These altitudes are published on aeronautical must cross when proceeding in the direction of a charts and prescribed in 14 CFR Part 95 for airways higher minimum en route IFR altitude (MEA). and routes, and in 14 CFR Part 97 for standard (See MINIMUM EN ROUTE IFR ALTITUDE.) instrument approach procedures. If no applicable MINIMUM DESCENT ALTITUDE (MDA)− The minimum altitude is prescribed in 14 CFR Part 95 or lowest altitude, expressed in feet above mean sea 14 CFR Part 97, the following minimum IFR level, to which descent is authorized on final altitude applies: approach or during circle-to-land maneuvering in a. In designated mountainous areas, 2,000 feet execution of a standard instrument approach above the highest obstacle within a horizontal procedure where no electronic glideslope is provided. distance of 4 nautical miles from the course to be (See NONPRECISION APPROACH flown; or PROCEDURE.) b. Other than mountainous areas, 1,000 feet above MINIMUM EN ROUTE IFR ALTITUDE (MEA)− the highest obstacle within a horizontal distance of 4 The lowest published altitude between radio fixes nautical miles from the course to be flown; or

PCG M−3 Pilot/Controller Glossary 6/17/21

c. As otherwise authorized by the Administrator published procedures as “Emergency Safe or assigned by ATC. Altitudes.” (See MINIMUM CROSSING ALTITUDE.) MINIMUM SAFE ALTITUDE WARNING (See MINIMUM EN ROUTE IFR ALTITUDE.) (MSAW)− A function of the EAS and STARS (See MINIMUM OBSTRUCTION CLEARANCE computer that aids the controller by alerting him/her ALTITUDE.) when a tracked Mode C equipped aircraft is below or (See MINIMUM SAFE ALTITUDE.) is predicted by the computer to go below a (See MINIMUM VECTORING ALTITUDE.) predetermined minimum safe altitude. (Refer to 14 CFR Part 91.) (Refer to AIM.) MINIMUM OBSTRUCTION CLEARANCE ALTI- MINIMUM SECTOR ALTITUDE [ICAO]− The TUDE (MOCA)− The lowest published altitude in lowest altitude which may be used under emergency effect between radio fixes on VOR airways, conditions which will provide a minimum clearance off-airway routes, or route segments which meets of 300 m (1,000 feet) above all obstacles located in obstacle clearance requirements for the entire route an area contained within a sector of a circle of 46 km segment and which assures acceptable navigational (25 NM) radius centered on a radio aid to navigation. signal coverage only within 25 statute (22 nautical) MINIMUMS− Weather condition requirements miles of a VOR. established for a particular operation or type of (Refer to 14 CFR Part 91.) operation; e.g., IFR takeoff or landing, alternate (Refer to 14 CFR Part 95.) airport for IFR flight plans, VFR flight, etc. MINIMUM RECEPTION ALTITUDE (MRA)− The (See IFR CONDITIONS.) lowest altitude at which an intersection can be (See IFR TAKEOFF MINIMUMS AND determined. DEPARTURE PROCEDURES.) (Refer to 14 CFR Part 95.) (See LANDING MINIMUMS.) (See VFR CONDITIONS.) MINIMUM SAFE ALTITUDE (MSA)− (Refer to 14 CFR Part 91.) a. The minimum altitude specified in 14 CFR (Refer to AIM.) Part 91 for various aircraft operations. MINIMUM VECTORING ALTITUDE (MVA)− b. Altitudes depicted on approach charts which The lowest MSL altitude at which an IFR aircraft will provide at least 1,000 feet of obstacle clearance for be vectored by a radar controller, except as otherwise emergency use. These altitudes will be identified as authorized for radar approaches, departures, and Minimum Safe Altitudes or Emergency Safe missed approaches. The altitude meets IFR obstacle Altitudes and are established as follows: clearance criteria. It may be lower than the published 1. Minimum Safe Altitude (MSA). Altitudes MEA along an airway or J-route segment. It may be depicted on approach charts which provide at least utilized for radar vectoring only upon the controller’s 1,000 feet of obstacle clearance within a 25-mile determination that an adequate radar return is being radius of the navigation facility, waypoint, or airport received from the aircraft being controlled. Charts reference point upon which the MSA is predicated. depicting minimum vectoring altitudes are normally MSAs are for emergency use only and do not available only to the controllers and not to pilots. necessarily assure acceptable navigational signal (Refer to AIM.) coverage. MINUTES-IN-TRAIL− A specified interval be- (See ICAO term Minimum Sector Altitude.) tween aircraft expressed in time. This method would 2. Emergency Safe Altitude (ESA). Altitudes more likely be utilized regardless of altitude. depicted on approach charts which provide at least MIS− 1,000 feet of obstacle clearance in nonmountainous (See METEOROLOGICAL IMPACT areas and 2,000 feet of obstacle clearance in STATEMENT.) designated mountainous areas within a 100-mile radius of the navigation facility or waypoint used as MISSED APPROACH− the ESA center. These altitudes are normally used a. A maneuver conducted by a pilot when an only in military procedures and are identified on instrument approach cannot be completed to a

PCG M−4 6/17/21 Pilot/Controller Glossary

landing. The route of flight and altitude are shown on Mode C (altitude reporting) are used in air traffic instrument approach procedure charts. A pilot control. executing a missed approach prior to the Missed (See INTERROGATOR.) Approach Point (MAP) must continue along the final (See RADAR.) approach to the MAP. (See TRANSPONDER.) (See ICAO term MODE.) b. A term used by the pilot to inform ATC that (Refer to AIM.) he/she is executing the missed approach. MODE (SSR MODE) [ICAO]− The letter or number c. At locations where ATC radar service is assigned to a specific pulse spacing of the provided, the pilot should conform to radar vectors interrogation signals transmitted by an interrogator. when provided by ATC in lieu of the published There are 4 modes, A, B, C and D specified in Annex missed approach procedure. 10, corresponding to four different interrogation (See MISSED APPROACH POINT.) pulse spacings. (Refer to AIM.) MODE C INTRUDER ALERT− A function of certain air traffic control automated systems designed MISSED APPROACH POINT (MAP)− A point to alert radar controllers to existing or pending prescribed in each instrument approach procedure at situations between a tracked target (known IFR or which a missed approach procedure shall be executed VFR aircraft) and an untracked target (unknown IFR if the required visual reference does not exist. or VFR aircraft) that requires immediate attention/ac- (See MISSED APPROACH.) tion. (See CONFLICT ALERT.) (See SEGMENTS OF AN INSTRUMENT APPROACH PROCEDURE.) MODEL AIRCRAFT− An unmanned aircraft that is: (1) capable of sustained flight in the atmosphere; (2) MISSED APPROACH PROCEDURE [ICAO]− The flown within visual line of sight of the person procedure to be followed if the approach cannot be operating the aircraft; and (3) flown for hobby or continued. recreational purposes. MONITOR− (When used with communication MISSED APPROACH SEGMENT− transfer) listen on a specific frequency and stand by (See SEGMENTS OF AN INSTRUMENT for instructions. Under normal circumstances do not APPROACH PROCEDURE.) establish communications. MONITOR ALERT (MA)− A function of the TFMS MLDI− that provides traffic management personnel with a (See METER LIST DISPLAY INTERVAL.) tool for predicting potential capacity problems in individual operational sectors. The MA is an MM− indication that traffic management personnel need to (See MIDDLE MARKER.) analyze a particular sector for actual activity and to determine the required action(s), if any, needed to MOA− control the demand. (See MILITARY OPERATIONS AREA.) MONITOR ALERT PARAMETER (MAP)− The number designated for use in monitor alert MOCA− processing by the TFMS. The MAP is designated for each operational sector for increments of 15 minutes. (See MINIMUM OBSTRUCTION CLEARANCE ALTITUDE.) MOSAIC/MULTI−SENSOR MODE− Accepts posi- tional data from multiple radar or ADS−B sites. MODE− The letter or number assigned to a specific Targets are displayed from a single source within a pulse spacing of radio signals transmitted or received radar sort box according to the hierarchy of the by ground interrogator or airborne transponder sources assigned. components of the Air Traffic Control Radar Beacon MOUNTAIN WAVE– Mountain waves occur when System (ATCRBS). Mode A (military Mode 3) and air is being blown over a mountain range or even the

PCG M−5 Pilot/Controller Glossary 6/17/21

ridge of a sharp bluff area. As the air hits the upwind MRA− side of the range, it starts to climb, thus creating what (See MINIMUM RECEPTION ALTITUDE.) is generally a smooth updraft which turns into a turbulent downdraft as the air passes the crest of the MSA− ridge. Mountain waves can cause significant (See MINIMUM SAFE ALTITUDE.) fluctuations in airspeed and altitude with or without

associated turbulence. MSAW− (Refer to AIM.) (See MINIMUM SAFE ALTITUDE WARNING.) MOVEMENT AREA− The runways, taxiways, and MTI− other areas of an airport/heliport which are utilized (See MOVING TARGET INDICATOR.) for taxiing/hover taxiing, air taxiing, takeoff, and landing of aircraft, exclusive of loading ramps and MTR− parking areas. At those airports/heliports with a (See MILITARY TRAINING ROUTES.) tower, specific approval for entry onto the movement MULTICOM− A mobile service not open to public area must be obtained from ATC. correspondence used to provide communications (See ICAO term MOVEMENT AREA.) essential to conduct the activities being performed by MOVEMENT AREA [ICAO]− That part of an or directed from private aircraft. aerodrome to be used for the takeoff, landing and taxiing of aircraft, consisting of the maneuvering area MULTIPLE RUNWAYS− The utilization of a and the apron(s). dedicated arrival runway(s) for departures and a dedicated departure runway(s) for arrivals when MOVING TARGET INDICATOR− An electronic feasible to reduce delays and enhance capacity. device which will permit radar scope presentation only from targets which are in motion. A partial MVA− remedy for ground clutter. (See MINIMUM VECTORING ALTITUDE.)

PCG M−6 6/17/21 Pilot/Controller Glossary N

NAS− specified. Extended range is made possible (See NATIONAL AIRSPACE SYSTEM.) through flight inspection determinations. Some aids also have lesser service range due to location, NAT HLA– terrain, frequency protection, etc. Restrictions to (See NORTH ATLANTIC HIGH LEVEL service range are listed in Chart Supplement U.S. AIRSPACE.) NAVIGABLE AIRSPACE− Airspace at and above NATIONAL AIRSPACE SYSTEM− The common the minimum flight altitudes prescribed in the CFRs network of U.S. airspace; air navigation facilities, including airspace needed for safe takeoff and equipment and services, airports or landing areas; landing. aeronautical charts, information and services; rules, (Refer to 14 CFR Part 91.) regulations and procedures, technical information, NAVIGATION REFERENCE SYSTEM (NRS)− and manpower and material. Included are system The NRS is a system of waypoints developed for use components shared jointly with the military. within the United States for flight planning and NATIONAL BEACON CODE ALLOCATION navigation without reference to ground based PLAN AIRSPACE (NBCAP)− Airspace over United navigational aids. The NRS waypoints are located in States territory located within the North American a grid pattern along defined latitude and longitude continent between Canada and Mexico, including lines. The initial use of the NRS will be in the high adjacent territorial waters outward to about bound- altitude environment. The NRS waypoints are aries of oceanic control areas (CTA)/Flight intended for use by aircraft capable of point−to−point Information Regions (FIR). navigation. (See FLIGHT INFORMATION REGION.) NAVIGATION SPECIFICATION [ICAO]− A set of NATIONAL FLIGHT DATA DIGEST (NFDD)− A aircraft and flight crew requirements needed to daily (except weekends and Federal holidays) support performance−based navigation operations publication of flight information appropriate to within a defined airspace. There are two kinds of aeronautical charts, aeronautical publications, No- navigation specifications: tices to Airmen, or other media serving the purpose a. RNP specification. A navigation specification of providing operational flight data essential to safe based on area navigation that includes the and efficient aircraft operations. requirement for performance monitoring and alerting, designated by the prefix RNP; e.g., RNP 4, NATIONAL SEARCH AND RESCUE PLAN− An RNP APCH. interagency agreement which provides for the effective utilization of all available facilities in all b. RNAV specification. A navigation specifica- types of search and rescue missions. tion based on area navigation that does not include the requirement for performance monitoring and alert- NAVAID− ing, designated by the prefix RNAV; e.g., RNAV 5, (See NAVIGATIONAL AID.) RNAV 1. NAVAID CLASSES− VOR, VORTAC, and TACAN Note: The Performance−based Navigation Manual aids are classed according to their operational use. (Doc 9613), Volume II contains detailed guidance The three classes of NAVAIDs are: on navigation specifications. a. T− Terminal. NAVIGATIONAL AID− Any visual or electronic device airborne or on the surface which provides b. L− Low altitude. point-to-point guidance information or position data c. H− High altitude. to aircraft in flight. Note: The normal service range for T, L, and H class (See AIR NAVIGATION FACILITY.) aids is found in the AIM. Certain operational NAVSPEC- requirements make it necessary to use some of these aids at greater service ranges than (See NAVIGATION SPECIFICATION [ICAO].)

PCG N−1 Pilot/Controller Glossary 6/17/21

NBCAP AIRSPACE− by the tower or to transit the Class D airspace. The (See NATIONAL BEACON CODE ALLOCATION primary function of a nonapproach control tower is PLAN AIRSPACE.) the sequencing of aircraft in the traffic pattern and on the landing area. Nonapproach control towers also NDB− separate aircraft operating under instrument flight (See NONDIRECTIONAL BEACON.) rules clearances from approach controls and centers. NEGATIVE− “No,” or “permission not granted,” or They provide ground control services to aircraft, “that is not correct.” vehicles, personnel, and equipment on the airport movement area. NEGATIVE CONTACT− Used by pilots to inform ATC that: NONCOMMON ROUTE/PORTION− That segment a. Previously issued traffic is not in sight. It may of a North American Route between the inland be followed by the pilot’s request for the controller to navigation facility and a designated North American provide assistance in avoiding the traffic. terminal. b. They were unable to contact ATC on a NON−COOPERATIVE SURVEILLANCE− Any particular frequency. surveillance system, such as primary radar, that is not dependent upon the presence of any equipment on the NFDD− aircraft or vehicle to be tracked. (See NATIONAL FLIGHT DATA DIGEST.) (See COOPERATIVE SURVEILLANCE.) NIGHT− The time between the end of evening civil (See RADAR.) twilight and the beginning of morning civil twilight, NONDIRECTIONAL BEACON− An L/MF or UHF as published in the Air Almanac, converted to local radio beacon transmitting nondirectional signals time. whereby the pilot of an aircraft equipped with (See ICAO term NIGHT.) direction finding equipment can determine his/her NIGHT [ICAO]− The hours between the end of bearing to or from the radio beacon and “home” on or evening civil twilight and the beginning of morning track to or from the station. When the radio beacon is civil twilight or such other period between sunset and installed in conjunction with the Instrument Landing sunrise as may be specified by the appropriate System marker, it is normally called a Compass authority. Locator. Note: Civil twilight ends in the evening when the (See AUTOMATIC DIRECTION FINDER.) center of the sun’s disk is 6 degrees below the (See COMPASS LOCATOR.) horizon and begins in the morning when the center NONMOVEMENT AREAS− Taxiways and apron of the sun’s disk is 6 degrees below the horizon. (ramp) areas not under the control of air traffic. NO GYRO APPROACH− A radar approach/vector NONPRECISION APPROACH− provided in case of a malfunctioning gyro-compass (See NONPRECISION APPROACH or directional gyro. Instead of providing the pilot PROCEDURE.) with headings to be flown, the controller observes the radar track and issues control instructions “turn NONPRECISION APPROACH PROCEDURE− A right/left” or “stop turn” as appropriate. standard instrument approach procedure in which no (Refer to AIM.) electronic glideslope is provided; e.g., VOR, TACAN, NDB, LOC, ASR, LDA, or SDF NO GYRO VECTOR− approaches. (See NO GYRO APPROACH.) NONRADAR− Precedes other terms and generally NO TRANSGRESSION ZONE (NTZ)− The NTZ is means without the use of radar, such as: a 2,000 foot wide zone, located equidistant between a. Nonradar Approach. Used to describe parallel runway or SOIA final approach courses, in instrument approaches for which course guidance on which flight is normally not allowed. final approach is not provided by ground-based NONAPPROACH CONTROL TOWER− Author- precision or surveillance radar. Radar vectors to the izes aircraft to land or takeoff at the airport controlled final approach course may or may not be provided by

PCG N−2 6/17/21 Pilot/Controller Glossary

ATC. Examples of nonradar approaches are VOR, route systems to and from specific coastal fixes NDB, TACAN, ILS, RNAV, and GLS approaches. serving the North Atlantic. North American Routes (See FINAL APPROACH COURSE.) consist of the following: (See FINAL APPROACH-IFR.) a. Common Route/Portion. That segment of a (See INSTRUMENT APPROACH North American Route between the inland navigation PROCEDURE.) facility and the coastal fix. (See RADAR APPROACH.) b. Noncommon Route/Portion. That segment of a b. Nonradar Approach Control. An ATC facility North American Route between the inland navigation providing approach control service without the use of facility and a designated North American terminal. radar. c. Inland Navigation Facility. A navigation aid on (See APPROACH CONTROL FACILITY.) a North American Route at which the common route (See APPROACH CONTROL SERVICE.) and/or the noncommon route begins or ends. c. Nonradar Arrival. An aircraft arriving at an d. Coastal Fix. A navigation aid or intersection airport without radar service or at an airport served by where an aircraft transitions between the domestic a radar facility and radar contact has not been route structure and the oceanic route structure. established or has been terminated due to a lack of NORTH AMERICAN ROUTE PROGRAM (NRP)− radar service to the airport. The NRP is a set of rules and procedures which are (See RADAR ARRIVAL.) designed to increase the flexibility of user flight (See RADAR SERVICE.) planning within published guidelines. d. Nonradar Route. A flight path or route over NORTH ATLANTIC HIGH LEVEL AIRSPACE which the pilot is performing his/her own navigation. (NAT HLA)− That volume of airspace (as defined in The pilot may be receiving radar separation, radar ICAO Document 7030) between FL 285 and FL 420 monitoring, or other ATC services while on a within the Oceanic Control Areas of Bodo Oceanic, nonradar route. Gander Oceanic, New York Oceanic East, Reykjavik, (See RADAR ROUTE.) Santa Maria, and Shanwick, excluding the Shannon e. Nonradar Separation. The spacing of aircraft in and Brest Ocean Transition Areas. ICAO Doc 007 accordance with established minima without the use North Atlantic Operations and Airspace Manual of radar; e.g., vertical, lateral, or longitudinal provides detailed information on related aircraft and separation. operational requirements. (See RADAR SEPARATION.) NORTH PACIFIC− An organized route system between the Alaskan west coast and Japan. NON−RESTRICTIVE ROUTING (NRR)− Portions of a proposed route of flight where a user can flight NOT STANDARD− Varying from what is expected plan the most advantageous flight path with no or published. For use in NOTAMs only. requirement to make reference to ground−based NOT STD- NAVAIDs. (See NOT STANDARD.) NOPAC− NOTAM− (See NORTH PACIFIC.) (See NOTICE TO AIRMEN.) NOTAM [ICAO]− A notice containing information NORDO (No Radio)− Aircraft that cannot or do not concerning the establishment, condition or change in communicate by radio when radio communication is any aeronautical facility, service, procedure or required are referred to as “NORDO.” hazard, the timely knowledge of which is essential to (See LOST COMMUNICATIONS.) personnel concerned with flight operations. NORMAL OPERATING ZONE (NOZ)− The NOZ a. I Distribution− Distribution by means of is the operating zone within which aircraft flight telecommunication. remains during normal independent simultaneous b. II Distribution− Distribution by means other parallel ILS approaches. than telecommunications. NORTH AMERICAN ROUTE− A numerically NOTICE TO AIRMEN (NOTAM)− A notice coded route preplanned over existing airway and containing information (not known sufficiently in

PCG N−3 Pilot/Controller Glossary 6/17/21

advance to publicize by other means) concerning the nature, transmitted by USNOF and given system establishment, condition, or change in any wide dissemination. component (facility, service, or procedure of, or (See ICAO term NOTAM.) hazard in the National Airspace System) the timely NRR− knowledge of which is essential to personnel (See NON−RESTRICTIVE ROUTING.) concerned with flight operations. NRS− (See NAVIGATION REFERENCE SYSTEM.) NOTAM(D)− A NOTAM given (in addition to local dissemination) distant dissemination beyond the area NUMEROUS TARGETS VICINITY (LOCA- of responsibility of the Flight Service Station. These TION)− A traffic advisory issued by ATC to advise NOTAMs will be stored and available until canceled. pilots that targets on the radar scope are too numerous to issue individually. c. FDC NOTAM− A NOTAM regulatory in (See TRAFFIC ADVISORIES.)

PCG N−4 6/17/21 Pilot/Controller Glossary O

OBSTACLE− An existing object, object of natural (b) 180 feet, plus the wingspan of the most growth, or terrain at a fixed geographical location or demanding airplane, plus 20 feet per 1,000 feet of which may be expected at a fixed location within a airport elevation. prescribed area with reference to which vertical 2. For runways serving only small airplanes: clearance is or must be provided during flight (a) 300 feet for precision instrument run- operation. ways. OBSTACLE DEPARTURE PROCEDURE (ODP)− (b) 250 feet for other runways serving small A preplanned instrument flight rule (IFR) departure airplanes with approach speeds of 50 knots, or more. procedure printed for pilot use in textual or graphic (c) 120 feet for other runways serving small form to provide obstruction clearance via the least airplanes with approach speeds of less than 50 knots. onerous route from the terminal area to the b. Inner-approach OFZ. The inner-approach OFZ appropriate en route structure. ODPs are recom- is a defined volume of airspace centered on the mended for obstruction clearance and may be flown approach area. The inner-approach OFZ applies only without ATC clearance unless an alternate departure to runways with an approach lighting system. The procedure (SID or radar vector) has been specifically inner-approach OFZ begins 200 feet from the runway assigned by ATC. threshold at the same elevation as the runway (See IFR TAKEOFF MINIMUMS AND threshold and extends 200 feet beyond the last light DEPARTURE PROCEDURES.) unit in the approach lighting system. The width of the (See STANDARD INSTRUMENT inner-approach OFZ is the same as the runway OFZ DEPARTURES.) and rises at a slope of 50 (horizontal) to 1 (vertical) (Refer to AIM.) from the beginning. c. Inner-transitional OFZ. The inner transitional OBSTACLE FREE ZONE− The OFZ is a surface OFZ is a defined volume of airspace along the three−dimensional volume of airspace which protects sides of the runway and inner-approach OFZ and for the transition of aircraft to and from the runway. applies only to precision instrument runways. The The OFZ clearing standard precludes taxiing and inner-transitional surface OFZ slopes 3 (horizontal) parked airplanes and object penetrations, except for to 1 (vertical) out from the edges of the runway OFZ frangible NAVAID locations that are fixed by and inner-approach OFZ to a height of 150 feet above function. Additionally, vehicles, equipment, and the established airport elevation. personnel may be authorized by air traffic control to (Refer to AC 150/5300-13, Chapter 3.) enter the area using the provisions of FAA Order (Refer to FAA Order JO 7110.65, Para 3−1−5, JO 7110.65, paragraph 3−1−5, Vehicles/Equipment/ Vehicles/Equipment/Personnel Near/On Personnal Near/On Runways. The runway OFZ and Runways.) when applicable, the inner-approach OFZ, and the OBSTRUCTION− Any object/obstacle exceeding inner-transitional OFZ, comprise the OFZ. the obstruction standards specified by 14 CFR a. Runway OFZ. The runway OFZ is a defined Part 77, Subpart C. volume of airspace centered above the runway. The OBSTRUCTION LIGHT− A light or one of a group runway OFZ is the airspace above a surface whose of lights, usually red or white, frequently mounted on elevation at any point is the same as the elevation of a surface structure or natural terrain to warn pilots of the nearest point on the runway centerline. The the presence of an obstruction. runway OFZ extends 200 feet beyond each end of the runway. The width is as follows: OCEANIC AIRSPACE− Airspace over the oceans of the world, considered international airspace, where 1. For runways serving large airplanes, the oceanic separation and procedures per the Interna- greater of: tional Civil Aviation Organization are applied. (a) 400 feet, or Responsibility for the provisions of air traffic control

PCG O−1 Pilot/Controller Glossary 6/17/21

service in this airspace is delegated to various b. Used by ATC to advise a pilot making a radar countries, based generally upon geographic proxim- approach that his/her aircraft is lined up on the final ity and the availability of the required resources. approach course. (See ON-COURSE INDICATION.) OCEANIC ERROR REPORT− A report filed when ATC observes an Oceanic Error as defined by FAA ON-COURSE INDICATION− An indication on an Order 7110.82, Reporting Oceanic Errors. instrument, which provides the pilot a visual means of determining that the aircraft is located on the OCEANIC PUBLISHED ROUTE− A route estab- centerline of a given navigational track, or an lished in international airspace and charted or indication on a radar scope that an aircraft is on a described in flight information publications, such as given track. Route Charts, DOD En route Charts, Chart Supplements, NOTAMs, and Track Messages. ONE-MINUTE WEATHER− The most recent one minute updated weather broadcast received by a pilot OCEANIC TRANSITION ROUTE− An ATS route from an uncontrolled airport ASOS/AWOS. established for the purpose of transitioning aircraft ONER− to/from an organized track system. (See OCEANIC NAVIGATIONAL ERROR ODP− REPORT.) (See OBSTACLE DEPARTURE PROCEDURE.) OPERATIONAL− OFF COURSE− A term used to describe a situation (See DUE REGARD.) where an aircraft has reported a position fix or is OPERATIONS SPECIFICATIONS [ICAO]− The observed on radar at a point not on the ATC-approved authorizations, conditions and limitations associated route of flight. with the air operator certificate and subject to the conditions in the operations manual. OFF-ROUTE VECTOR− A vector by ATC which takes an aircraft off a previously assigned route. OPPOSITE DIRECTION AIRCRAFT− Aircraft are Altitudes assigned by ATC during such vectors operating in opposite directions when: provide required obstacle clearance. a. They are following the same track in reciprocal directions; or OFFSET PARALLEL RUNWAYS− Staggered runways having centerlines which are parallel. b. Their tracks are parallel and the aircraft are flying in reciprocal directions; or OFFSHORE/CONTROL AIRSPACE AREA− That c. Their tracks intersect at an angle of more than portion of airspace between the U.S. 12 NM limit and 135. the oceanic CTA/FIR boundary within which air traffic control is exercised. These areas are OPTION APPROACH− An approach requested and established to provide air traffic control services. conducted by a pilot which will result in either a Offshore/Control Airspace Areas may be classified touch-and-go, missed approach, low approach, as either Class A airspace or Class E airspace. stop-and-go, or full stop landing. Pilots should advise ATC if they decide to remain on the runway, of any OFT− delay in their stop and go, delay clearing the runway, (See OUTER FIX TIME.) or are unable to comply with the instruction(s). (See CLEARED FOR THE OPTION.) OM− (Refer to AIM.) (See OUTER MARKER.) ORGANIZED TRACK SYSTEM− A series of ATS ON COURSE− routes which are fixed and charted; i.e., CEP, a. Used to indicate that an aircraft is established on NOPAC, or flexible and described by NOTAM; i.e., the route centerline. NAT TRACK MESSAGE.

PCG O−2 6/17/21 Pilot/Controller Glossary

OFF−ROUTE OBSTRUCTION CLEARANCE AL- OR TITUDE (OROCA)− An off-route altitude which OUTER FIX− An adapted fix along the converted provides obstruction clearance with a 1,000 foot route of flight, prior to the meter fix, for which buffer in non−mountainous terrain areas and a 2,000 crossing times are calculated and displayed in the foot buffer in designated mountainous areas within metering position list. the United States. This altitude may not provide signal coverage from ground-based navigational OUTER FIX ARC− A semicircle, usually about a aids, air traffic control radar, or communications 50−70 mile radius from a meter fix, usually in high coverage. altitude, which is used by CTAS/ERAM to calculate outer fix times and determine appropriate sector OTR− meter list assignments for aircraft on an established (See OCEANIC TRANSITION ROUTE.) arrival route that will traverse the arc. OTS− OUTER FIX TIME− A calculated time to depart the (See ORGANIZED TRACK SYSTEM.) outer fix in order to cross the vertex at the ACLT. The OUT− The conversation is ended and no response is time reflects descent speed adjustments and any expected. applicable delay time that must be absorbed prior to crossing the meter fix. OUT OF SERVICE/UNSERVICEABLE (U/S)− OUTER MARKER− A marker beacon at or near the When a piece of equipment, a NAVAID, a facility or glideslope intercept altitude of an ILS approach. It is a service is not operational, certified (if required) and keyed to transmit two dashes per second on a 400 Hz immediately “available” for Air Traffic or public use. tone, which is received aurally and visually by OUTER AREA (associated with Class C airspace)− compatible airborne equipment. The OM is normally Non−regulatory airspace surrounding designated located four to seven miles from the runway threshold Class C airspace airports wherein ATC provides radar on the extended centerline of the runway. vectoring and sequencing on a full-time basis for all (See INSTRUMENT LANDING SYSTEM.) IFR and participating VFR aircraft. The service (See MARKER BEACON.) provided in the outer area is called Class C service (Refer to AIM.) which includes: IFR/IFR−IFR separation; IFR/ OVER− My transmission is ended; I expect a VFR−traffic advisories and conflict resolution; and response. VFR/VFR−traffic advisories and, as appropriate, safety alerts. The normal radius will be 20 nautical OVERHEAD MANEUVER− A series of predeter- miles with some variations based on site-specific mined maneuvers prescribed for aircraft (often in requirements. The outer area extends outward from formation) for entry into the visual flight rules (VFR) the primary Class C airspace airport and extends from traffic pattern and to proceed to a landing. An the lower limits of radar/radio coverage up to the overhead maneuver is not an instrument flight rules ceiling of the approach control’s delegated airspace (IFR) approach procedure. An aircraft executing an excluding the Class C charted area and other airspace overhead maneuver is considered VFR and the IFR as appropriate. flight plan is canceled when the aircraft reaches the (See CONFLICT RESOLUTION.) “initial point” on the initial approach portion of the (See CONTROLLED AIRSPACE.) maneuver. The pattern usually specifies the following: OUTER COMPASS LOCATOR− a. The radio contact required of the pilot. (See COMPASS LOCATOR.) b. The speed to be maintained. OUTER FIX− A general term used within ATC to c. An initial approach 3 to 5 miles in length. describe fixes in the terminal area, other than the final d. An elliptical pattern consisting of two 180 approach fix. Aircraft are normally cleared to these degree turns. fixes by an Air Route Traffic Control Center or an Approach Control Facility. Aircraft are normally e. A break point at which the first 180 degree turn cleared from these fixes to the final approach fix or is started. final approach course. f. The direction of turns.

PCG O−3 Pilot/Controller Glossary 6/17/21

g. Altitude (at least 500 feet above the convention- OVERLYING CENTER− The ARTCC facility that al pattern). is responsible for arrival/departure operations at a h. A “Roll-out” on final approach not less than 1/4 specific terminal. mile from the landing threshold and not less than 300 feet above the ground.

PCG O−4 6/17/21 Pilot/Controller Glossary P

P TIME− PERFORMANCE−BASED NAVIGATION (PBN) (See PROPOSED DEPARTURE TIME.) [ICAO]− Area navigation based on performance requirements for aircraft operating along an ATS P-ACP− route, on an instrument approach procedure or in a (See PREARRANGED COORDINATION designated airspace. PROCEDURES.) Note: Performance requirements are expressed in PAN-PAN− The international radio-telephony urgen- navigation specifications (RNAV specification, cy signal. When repeated three times, indicates RNP specification) in terms of accuracy, integrity, uncertainty or alert followed by the nature of the continuity, availability, and functionality needed for urgency. the proposed operation in the context of a particular airspace concept. (See MAYDAY.) (Refer to AIM.) PERMANENT ECHO− Radar signals reflected from fixed objects on the earth’s surface; e.g., buildings, PAR− towers, terrain. Permanent echoes are distinguished (See PRECISION APPROACH RADAR.) from “ground clutter” by being definable locations PAR [ICAO]− rather than large areas. Under certain conditions they (See ICAO Term PRECISION APPROACH may be used to check radar alignment. RADAR.) PHOTO RECONNAISSANCE− Military activity PARALLEL ILS APPROACHES− Approaches to that requires locating individual photo targets and parallel runways by IFR aircraft which, when navigating to the targets at a preplanned angle and established inbound toward the airport on the altitude. The activity normally requires a lateral route adjacent final approach courses, are radar-separated width of 16 NM and altitude range of 1,500 feet to by at least 2 miles. 10,000 feet AGL. (See FINAL APPROACH COURSE.) PILOT BRIEFING− A service provided by the FSS (See SIMULTANEOUS ILS APPROACHES.) to assist pilots in flight planning. Briefing items may PARALLEL OFFSET ROUTE− A parallel track to include weather information, NOTAMS, military the left or right of the designated or established activities, flow control information, and other items airway/route. Normally associated with Area Navi- as requested. gation (RNAV) operations. (Refer to AIM.) (See AREA NAVIGATION.) PILOT IN COMMAND− The pilot responsible for PARALLEL RUNWAYS− Two or more runways at the operation and safety of an aircraft during flight the same airport whose centerlines are parallel. In time. addition to runway number, parallel runways are (Refer to 14 CFR Part 91.) designated as L (left) and R (right) or, if three parallel PILOT WEATHER REPORT− A report of meteoro- runways exist, L (left), C (center), and R (right). logical phenomena encountered by aircraft in flight. PBCT− (Refer to AIM.) (See PROPOSED BOUNDARY CROSSING PILOT’S DISCRETION− When used in conjunc- TIME.) tion with altitude assignments, means that ATC has PBN− offered the pilot the option of starting climb or (See ICAO Term PERFORMANCE−BASED descent whenever he/she wishes and conducting the NAVIGATION.) climb or descent at any rate he/she wishes. He/she may temporarily level off at any intermediate PDC− altitude. However, once he/she has vacated an (See PRE−DEPARTURE CLEARANCE.) altitude, he/she may not return to that altitude.

PCG P−1 Pilot/Controller Glossary 6/17/21

PIREP− PREARRANGED COORDINATION PROCE- (See PILOT WEATHER REPORT.) DURES− A facility’s standardized procedure that describes the process by which one controller shall PITCH POINT− A fix/waypoint that serves as a allow an aircraft to penetrate or transit another transition point from a departure procedure or the low controller’s airspace in a manner that assures altitude ground−based navigation structure into the approved separation without individual coordination high altitude waypoint system. for each aircraft. PLANS DISPLAY− A display available in EDST PRECIPITATION− Any or all forms of water that provides detailed flight plan and predicted particles (rain, sleet, hail, or snow) that fall from the conflict information in textual format for requested atmosphere and reach the surface. Current Plans and all Trial Plans. (See EN ROUTE DECISION SUPPORT TOOL) PRECIPITATION RADAR WEATHER DESCRIP- TIONS− Existing radar systems cannot detect POFZ− turbulence. However, there is a direct correlation (See PRECISION OBSTACLE FREE ZONE.) between the degree of turbulence and other weather POINT OUT− features associated with thunderstorms and the (See RADAR POINT OUT.) weather radar precipitation intensity. Controllers will issue (where capable) precipitation intensity as POINT−TO−POINT (PTP)− A level of NRR service observed by radar when using weather and radar for aircraft that is based on traditional waypoints in processor (WARP) or NAS ground−based digital their FMSs or RNAV equipage. radars with weather capabilities. When precipitation POLAR TRACK STRUCTURE− A system of intensity information is not available, the intensity organized routes between Iceland and Alaska which will be described as UNKNOWN. When intensity overlie Canadian MNPS Airspace. levels can be determined, they shall be described as: a. LIGHT (< 26 dBZ) POSITION REPORT− A report over a known location as transmitted by an aircraft to ATC. b. MODERATE (26 to 40 dBZ) (Refer to AIM.) c. HEAVY (> 40 to 50 dBZ) d. EXTREME (> 50 dBZ) POSITION SYMBOL− A computer-generated indication shown on a radar display to indicate the (Refer to AC 00−45, Aviation Weather Services.) mode of tracking. PRECISION APPROACH− POSITIVE CONTROL− The separation of all air (See PRECISION APPROACH PROCEDURE.) traffic within designated airspace by air traffic PRECISION APPROACH PROCEDURE− A control. standard instrument approach procedure in which an electronic glideslope or other type of glidepath is PRACTICE INSTRUMENT APPROACH− An provided; e.g., ILS, PAR, and GLS. instrument approach procedure conducted by a VFR or an IFR aircraft for the purpose of pilot training or (See INSTRUMENT LANDING SYSTEM.) proficiency demonstrations. (See PRECISION APPROACH RADAR.) PRECISION APPROACH RADAR− Radar equip- PRE−DEPARTURE CLEARANCE− An application ment in some ATC facilities operated by the FAA with the Terminal Data Link System (TDLS) that and/or the military services at joint-use civil/military provides clearance information to subscribers, locations and separate military installations to detect through a service provider, in text to the cockpit or and display azimuth, elevation, and range of aircraft gate printer. on the final approach course to a runway. This PREARRANGED COORDINATION− A standard- equipment may be used to monitor certain non−radar ized procedure which permits an air traffic controller approaches, but is primarily used to conduct a to enter the airspace assigned to another air traffic precision instrument approach (PAR) wherein the controller without verbal coordination. The proce- controller issues guidance instructions to the pilot dures are defined in a facility directive which ensures based on the aircraft’s position in relation to the final approved separation between aircraft. approach course (azimuth), the glidepath (elevation),

PCG P−2 6/17/21 Pilot/Controller Glossary

and the distance (range) from the touchdown point on aircraft’s heading at or below 1200’ AGL. Departing the runway as displayed on the radar scope. flights may receive a wind shear alert after they start Note: The abbreviation “PAR” is also used to the takeoff roll and may elect to abort the takeoff. denote preferential arrival routes in ARTCC Aircraft on approach receiving an alert may elect to computers. go around or perform a wind shear escape maneuver. (See GLIDEPATH.) PREFERENTIAL ROUTES− Preferential routes (See PAR.) (PDRs, PARs, and PDARs) are adapted in ARTCC (See PREFERENTIAL ROUTES.) computers to accomplish inter/intrafacility controller (See ICAO term PRECISION APPROACH coordination and to assure that flight data is posted at RADAR.) the proper control positions. Locations having a need (Refer to AIM.) for these specific inbound and outbound routes PRECISION APPROACH RADAR [ICAO]− Pri- normally publish such routes in local facility mary radar equipment used to determine the position bulletins, and their use by pilots minimizes flight of an aircraft during final approach, in terms of lateral plan route amendments. When the workload or traffic and vertical deviations relative to a nominal approach situation permits, controllers normally provide radar path, and in range relative to touchdown. vectors or assign requested routes to minimize circuitous routing. Preferential routes are usually Note: Precision approach radars are designed to enable pilots of aircraft to be given guidance by confined to one ARTCC’s area and are referred to by radio communication during the final stages of the the following names or acronyms: approach to land. a. Preferential Departure Route (PDR). A specific departure route from an airport or terminal area to an PRECISION OBSTACLE FREE ZONE (POFZ)− en route point where there is no further need for flow An 800 foot wide by 200 foot long area centered on control. It may be included in an Instrument the runway centerline adjacent to the threshold Departure Procedure (DP) or a Preferred IFR Route. designed to protect aircraft flying precision b. Preferential Arrival Route (PAR). A specific approaches from ground vehicles and other aircraft arrival route from an appropriate en route point to an when ceiling is less than 250 feet or visibility is less airport or terminal area. It may be included in a than 3/4 statute mile (or runway visual range below Standard Terminal Arrival (STAR) or a Preferred IFR 4,000 feet.) Route. The abbreviation “PAR” is used primarily PRECISION RUNWAY MONITOR (PRM) within the ARTCC and should not be confused with SYSTEM− Provides air traffic controllers the abbreviation for Precision Approach Radar. monitoring the NTZ during simultaneous close c. Preferential Departure and Arrival Route parallel PRM approaches with precision, high update (PDAR). A route between two terminals which are rate secondary surveillance data. The high update rate within or immediately adjacent to one ARTCC’s area. surveillance sensor component of the PRM system is PDARs are not synonymous with Preferred IFR only required for specific runway or approach course Routes but may be listed as such as they do separation. The high resolution color monitoring accomplish essentially the same purpose. display, Final Monitor Aid (FMA) of the PRM (See PREFERRED IFR ROUTES.) system, or other FMA with the same capability, PREFERRED IFR ROUTES− Routes established presents NTZ surveillance track data to controllers between busier airports to increase system efficiency along with detailed maps depicting approaches and and capacity. They normally extend through one or no transgression zone and is required for all more ARTCC areas and are designed to achieve simultaneous close parallel PRM NTZ monitoring balanced traffic flows among high density terminals. operations. IFR clearances are issued on the basis of these routes (Refer to AIM) except when severe weather avoidance procedures or PREDICTIVE WIND SHEAR ALERT SYSTEM other factors dictate otherwise. Preferred IFR Routes (PWS)− A self−contained system used on board some are listed in the Chart Supplement U.S. If a flight is aircraft to alert the flight crew to the presence of a planned to or from an area having such routes but the potential wind shear. PWS systems typically monitor departure or arrival point is not listed in the Chart 3 miles ahead and 25 degrees left and right of the Supplement U.S., pilots may use that part of a

PCG P−3 Pilot/Controller Glossary 6/17/21

Preferred IFR Route which is appropriate for the 3000 feet. Runway spacing can be as close as 750 departure or arrival point that is listed. Preferred IFR feet. Routes are correlated with DPs and STARs and may (Refer to AIM.) be defined by airways, jet routes, direct routes PROCEDURAL CONTROL [ICAO]– Term used to between NAVAIDs, Waypoints, NAVAID radials/ indicate that information derived from an ATS DME, or any combinations thereof. surveillance system is not required for the provision (See CENTER’S AREA.) of air traffic control service. (See INSTRUMENT DEPARTURE PROCEDURAL SEPARATION [ICAO]– The sepa- PROCEDURE.) ration used when providing procedural control. (See PREFERENTIAL ROUTES.) (See STANDARD TERMINAL ARRIVAL.) PROCEDURE TURN− The maneuver prescribed when it is necessary to reverse direction to establish (Refer to CHART SUPPLEMENT U.S.) an aircraft on the intermediate approach segment or PRE-FLIGHT PILOT BRIEFING− final approach course. The outbound course, direction of turn, distance within which the turn must (See PILOT BRIEFING.) be completed, and minimum altitude are specified in PREVAILING VISIBILITY− the procedure. However, unless otherwise restricted, the point at which the turn may be commenced and (See VISIBILITY.) the type and rate of turn are left to the discretion of the PRIMARY RADAR TARGET− An analog or digital pilot. target, exclusive of a secondary radar target, (See ICAO term PROCEDURE TURN.) presented on a radar display. PROCEDURE TURN [ICAO]− A maneuver in which a turn is made away from a designated track PRM− followed by a turn in the opposite direction to permit (See AREA NAVIGATION (RNAV) GLOBAL the aircraft to intercept and proceed along the POSITIONING SYSTEM (GPS) PRECISION reciprocal of the designated track. RUNWAY MONITORING (PRM) APPROACH.) Note 1: Procedure turns are designated “left” or (See PRM APPROACH.) “right” according to the direction of the initial turn. (See PRECISION RUNWAY MONITOR Note 2: Procedure turns may be designated as SYSTEM.) being made either in level flight or while descending, according to the circumstances of PRM APPROACH− An instrument approach each individual approach procedure. procedure titled ILS PRM, RNAV PRM, LDA PRM, or GLS PRM conducted to parallel runways PROCEDURE TURN INBOUND− That point of a separated by less than 4,300 feet and at least 3,000 procedure turn maneuver where course reversal has feet where independent closely spaced approaches been completed and an aircraft is established inbound are permitted. Use of an enhanced display with on the intermediate approach segment or final alerting, a No Transgression Zone (NTZ), secondary approach course. A report of “procedure turn monitor frequency, pilot PRM training, and inbound” is normally used by ATC as a position publication of an Attention All Users Page are report for separation purposes. required for all PRM approaches. Depending on the (See FINAL APPROACH COURSE.) runway spacing, the approach courses may be parallel (See PROCEDURE TURN.) or one approach course must be offset. PRM (See SEGMENTS OF AN INSTRUMENT procedures are also used to conduct Simultaneous APPROACH PROCEDURE.) Offset Instrument Approach (SOIA) operations. In PROFILE DESCENT− An uninterrupted descent SOIA, one straight−in ILS PRM, RNAV PRM, GLS (except where level flight is required for speed PRM, and one offset LDA PRM, RNAV PRM or adjustment; e.g., 250 knots at 10,000 feet MSL) from GLS PRM approach are utilized. PRM procedures cruising altitude/level to interception of a glideslope are terminated and a visual segment begins at the or to a minimum altitude specified for the initial or offset approach missed approach point where the intermediate approach segment of a nonprecision minimum distance between the approach courses is instrument approach. The profile descent normally

PCG P−4 6/17/21 Pilot/Controller Glossary

terminates at the approach gate or where the to the adjacent center if the flight time along the glideslope or other appropriate minimum altitude is proposed route from the departure airport to the intercepted. center boundary is less than or equal to the value of PBCT or if airport adaptation specifies transmission PROGRESS REPORT− regardless of PBCT. (See POSITION REPORT.) PROPOSED DEPARTURE TIME− The time that the PROGRESSIVE TAXI− Precise taxi instructions aircraft expects to become airborne. given to a pilot unfamiliar with the airport or issued in stages as the aircraft proceeds along the taxi route. PROTECTED AIRSPACE− The airspace on either side of an oceanic route/track that is equal to one-half PROHIBITED AREA− the lateral separation minimum except where (See SPECIAL USE AIRSPACE.) reduction of protected airspace has been authorized. (See ICAO term PROHIBITED AREA.) PROTECTED SEGMENT- The protected segment is

PROHIBITED AREA [ICAO]− An airspace of a segment on the amended TFM route that is to be defined dimensions, above the land areas or territorial inhibited from automatic adapted route alteration by waters of a State, within which the flight of aircraft ERAM. is prohibited. PT− PROMINENT OBSTACLE– An obstacle that meets (See PROCEDURE TURN.) one or more of the following conditions: a. An obstacle which stands out beyond the PTP− adjacent surface of surrounding terrain and immedi- (See POINT−TO−POINT.) ately projects a noticeable hazard to aircraft in flight. PTS− b. An obstacle, not characterized as low and close (See POLAR TRACK STRUCTURE.) in, whose height is no less than 300 feet above the PUBLISHED INSTRUMENT APPROACH departure end of takeoff runway (DER) elevation, is PROCEDURE VISUAL SEGMENT− A segment on within 10 NM from the DER, and that penetrates that an IAP chart annotated as “Fly Visual to Airport” or airport/heliport’s diverse departure obstacle clear- “Fly Visual.” A dashed arrow will indicate the visual ance surface (OCS). flight path on the profile and plan view with an c. An obstacle beyond 10 NM from an airport/ associated note on the approximate heading and heliport that requires an obstacle departure procedure distance. The visual segment should be flown as a (ODP) to ensure obstacle avoidance. dead reckoning course while maintaining visual (See OBSTACLE.) conditions. (See OBSTRUCTION.) PUBLISHED ROUTE− A route for which an IFR PROPELLER (PROP) WASH (PROP BLAST)− The altitude has been established and published; e.g., disturbed mass of air generated by the motion of a Federal Airways, Jet Routes, Area Navigation propeller. Routes, Specified Direct Routes. PROPOSED BOUNDARY CROSSING TIME− PWS− Each center has a PBCT parameter for each internal (See PREDICTIVE WIND SHEAR ALERT airport. Proposed internal flight plans are transmitted SYSTEM.)

PCG P−5

6/17/21 Pilot/Controller Glossary Q

Q ROUTE− ‘Q’ is the designator assigned to as follows: NE quadrant 000-089, SE quadrant published RNAV routes used by the United States. 090-179, SW quadrant 180-269, NW quadrant 270-359. QFE− The atmospheric pressure at aerodrome elevation (or at runway threshold). QUEUING− QNE− The barometric pressure used for the standard altimeter setting (29.92 inches Hg.). (See STAGING/QUEUING.) QNH− The barometric pressure as reported by a QUICK LOOK− A feature of the EAS and STARS particular station. which provides the controller the capability to QUADRANT− A quarter part of a circle, centered on display full data blocks of tracked aircraft from other a NAVAID, oriented clockwise from magnetic north control positions.

PCG Q−1

6/17/21 Pilot/Controller Glossary R

RADAR− A device that provides information on RADAR APPROACH− An instrument approach range, azimuth, and/or elevation of objects by procedure which utilizes Precision Approach Radar measuring the time interval between transmission (PAR) or Airport Surveillance Radar (ASR). and reception of directional radio pulses and (See AIRPORT SURVEILLANCE RADAR.) correlating the angular orientation of the radiated (See INSTRUMENT APPROACH antenna beam or beams in azimuth and/or elevation. PROCEDURE.) (See PRECISION APPROACH RADAR.) a. Primary Radar− A radar system in which a (See SURVEILLANCE APPROACH.) minute portion of a radio pulse transmitted from a site is reflected by an object and then received back at that (See ICAO term RADAR APPROACH.) (Refer to AIM.) site for processing and display at an air traffic control facility. RADAR APPROACH [ICAO]− An approach, executed by an aircraft, under the direction of a radar b. Secondary Radar/Radar Beacon (ATCRBS)− A controller. radar system in which the object to be detected is fitted with cooperative equipment in the form of a RADAR APPROACH CONTROL FACILITY− A radio receiver/transmitter (transponder). Radar terminal ATC facility that uses radar and nonradar pulses transmitted from the searching transmitter/re- capabilities to provide approach control services to ceiver (interrogator) site are received in the aircraft arriving, departing, or transiting airspace cooperative equipment and used to trigger a controlled by the facility. distinctive transmission from the transponder. This (See APPROACH CONTROL SERVICE.) reply transmission, rather than a reflected signal, is a. Provides radar ATC services to aircraft then received back at the transmitter/receiver site for operating in the vicinity of one or more civil and/or processing and display at an air traffic control facility. military airports in a terminal area. The facility may (See COOPERATIVE SURVEILLANCE.) provide services of a ground controlled approach (See INTERROGATOR.) (GCA); i.e., ASR and PAR approaches. A radar (See NON−COOPERATIVE SURVEILLANCE.) approach control facility may be operated by FAA, USAF, US Army, USN, USMC, or jointly by FAA (See TRANSPONDER.) and a military service. Specific facility nomencla- (See ICAO term RADAR.) tures are used for administrative purposes only and (Refer to AIM.) are related to the physical location of the facility and the operating service generally as follows: RADAR [ICAO]− A radio detection device which provides information on range, azimuth and/or 1. Army Radar Approach Control (ARAC) elevation of objects. (US Army). 2. Radar Air Traffic Control Facility (RATCF) a. Primary Radar− Radar system which uses (USN/FAA and USMC/FAA). reflected radio signals. 3. Radar Approach Control (RAPCON) b. Secondary Radar− Radar system wherein a (USAF/FAA, USN/FAA, and USMC/FAA). radio signal transmitted from a radar station initiates 4. Terminal Radar Approach Control the transmission of a radio signal from another (TRACON) (FAA). station. 5. Airport Traffic Control Tower (ATCT) RADAR ADVISORY− The provision of advice and (FAA). (Only those towers delegated approach information based on radar observations. control authority.) (See ADVISORY SERVICE.) RADAR ARRIVAL− An aircraft arriving at an airport served by a radar facility and in radar contact RADAR ALTIMETER− with the facility. (See RADIO ALTIMETER.) (See NONRADAR.)

PCG R−1 Pilot/Controller Glossary 6/17/21

RADAR BEACON− RADAR FLIGHT FOLLOWING− The observation (See RADAR.) of the progress of radar−identified aircraft, whose primary navigation is being provided by the pilot, RADAR CLUTTER [ICAO]− The visual indication wherein the controller retains and correlates the on a radar display of unwanted signals. aircraft identity with the appropriate target or target RADAR CONTACT− symbol displayed on the radar scope. (See RADAR CONTACT.) a. Used by ATC to inform an aircraft that it is (See RADAR SERVICE.) identified using an approved ATC surveillance (Refer to AIM.) source on an air traffic controller’s display and that radar flight following will be provided until radar RADAR IDENTIFICATION− The process of service is terminated. Radar service may also be ascertaining that an observed radar target is the radar provided within the limits of necessity and capability. return from a particular aircraft. When a pilot is informed of “radar contact,” he/she (See RADAR CONTACT.) automatically discontinues reporting over compuls- (See RADAR SERVICE.) ory reporting points. RADAR IDENTIFIED AIRCRAFT− An aircraft, the (See ATC SURVEILLANCE SOURCE.) position of which has been correlated with an (See RADAR CONTACT LOST.) observed target or symbol on the radar display. (See RADAR FLIGHT FOLLOWING.) (See RADAR CONTACT.) (See RADAR SERVICE.) (See RADAR CONTACT LOST.) (See RADAR SERVICE TERMINATED.) RADAR MONITORING− (Refer to AIM.) (See RADAR SERVICE.) b. The term used to inform the controller that the RADAR NAVIGATIONAL GUIDANCE− aircraft is identified and approval is granted for the (See RADAR SERVICE.) aircraft to enter the receiving controllers airspace. RADAR POINT OUT− An action taken by a (See ICAO term RADAR CONTACT.) controller to transfer the radar identification of an aircraft to another controller if the aircraft will or may RADAR CONTACT [ICAO]− The situation which enter the airspace or protected airspace of another exists when the radar blip or radar position symbol of controller and radio communications will not be a particular aircraft is seen and identified on a radar transferred. display. RADAR REQUIRED− A term displayed on charts RADAR CONTACT LOST− Used by ATC to inform and approach plates and included in FDC NOTAMs a pilot that the surveillance data used to determine the to alert pilots that segments of either an instrument aircraft’s position is no longer being received, or is no approach procedure or a route are not navigable longer reliable and radar service is no longer being because of either the absence or unusability of a provided. The loss may be attributed to several NAVAID. The pilot can expect to be provided radar factors including the aircraft merging with weather or navigational guidance while transiting segments ground clutter, the aircraft operating below radar line labeled with this term. of sight coverage, the aircraft entering an area of poor (See RADAR ROUTE.) radar return, failure of the aircraft’s equipment, or (See RADAR SERVICE.) failure of the surveillance equipment. RADAR ROUTE− A flight path or route over which (See CLUTTER.) an aircraft is vectored. Navigational guidance and (See RADAR CONTACT.) altitude assignments are provided by ATC. RADAR ENVIRONMENT− An area in which radar (See FLIGHT PATH.) service may be provided. (See ROUTE.) (See ADDITIONAL SERVICES.) RADAR SEPARATION− (See RADAR CONTACT.) (See RADAR SERVICE.) (See RADAR SERVICE.) RADAR SERVICE− A term which encompasses one (See TRAFFIC ADVISORIES.) or more of the following services based on the use of

PCG R−2 6/17/21 Pilot/Controller Glossary

radar which can be provided by a controller to a pilot RADAR SURVEILLANCE− The radar observation of a radar identified aircraft. of a given geographical area for the purpose of a. Radar Monitoring− The radar flight-following performing some radar function. of aircraft, whose primary navigation is being RADAR TRAFFIC ADVISORIES− Advisories performed by the pilot, to observe and note deviations issued to alert pilots to known or observed radar from its authorized flight path, airway, or route. traffic which may affect the intended route of flight When being applied specifically to radar monitoring of their aircraft. of instrument approaches; i.e., with precision (See TRAFFIC ADVISORIES.) approach radar (PAR) or radar monitoring of RADAR TRAFFIC INFORMATION SERVICE− simultaneous ILS,RNAV and GLS approaches, it (See TRAFFIC ADVISORIES.) includes advice and instructions whenever an aircraft nears or exceeds the prescribed PAR safety limit or RADAR VECTORING [ICAO]− Provision of simultaneous ILS RNAV and GLS no transgression navigational guidance to aircraft in the form of zone. specific headings, based on the use of radar. (See ADDITIONAL SERVICES.) RADIAL− A magnetic bearing extending from a (See TRAFFIC ADVISORIES.) VOR/VORTAC/TACAN navigation facility. b. Radar Navigational Guidance− Vectoring RADIO− aircraft to provide course guidance. a. A device used for communication. c. Radar Separation− Radar spacing of aircraft in b. Used to refer to a flight service station; e.g., accordance with established minima. “Seattle Radio” is used to call Seattle FSS. (See ICAO term RADAR SERVICE.) RADIO ALTIMETER− Aircraft equipment which RADAR SERVICE [ICAO]− Term used to indicate makes use of the reflection of radio waves from the a service provided directly by means of radar. ground to determine the height of the aircraft above a. Monitoring− The use of radar for the purpose of the surface. providing aircraft with information and advice RADIO BEACON− relative to significant deviations from nominal flight (See NONDIRECTIONAL BEACON.) path. RADIO DETECTION AND RANGING− b. Separation− The separation used when aircraft (See RADAR.) position information is derived from radar sources. RADIO MAGNETIC INDICATOR− An aircraft RADAR SERVICE TERMINATED− Used by ATC navigational instrument coupled with a gyro compass to inform a pilot that he/she will no longer be or similar compass that indicates the direction of a provided any of the services that could be received selected NAVAID and indicates bearing with respect while in radar contact. Radar service is automatically to the heading of the aircraft. terminated, and the pilot is not advised in the following cases: RAIS− (See REMOTE AIRPORT INFORMATION a. An aircraft cancels its IFR flight plan, except SERVICE.) within Class B airspace, Class C airspace, a TRSA, or where Basic Radar service is provided. RAMP− (See APRON.) b. An aircraft conducting an instrument, visual, or contact approach has landed or has been instructed to RANDOM ALTITUDE− An altitude inappropriate change to advisory frequency. for direction of flight and/or not in accordance with FAA Order JO 7110.65, paragraph 4−5−1, VER- c. An arriving VFR aircraft, receiving radar TICAL SEPARATION MINIMA. service to a tower-controlled airport within Class B airspace, Class C airspace, a TRSA, or where RANDOM ROUTE− Any route not established or sequencing service is provided, has landed; or to all charted/published or not otherwise available to all other airports, is instructed to change to tower or users. advisory frequency. RC− d. An aircraft completes a radar approach. (See ROAD RECONNAISSANCE.)

PCG R−3 Pilot/Controller Glossary 6/17/21

RCAG− RELEASE TIME [ICAO]− Time prior to which an (See REMOTE COMMUNICATIONS aircraft should be given further clearance or prior to AIR/GROUND FACILITY.) which it should not proceed in case of radio failure. RCC− REMOTE AIRPORT INFORMATION SERVICE (See RESCUE COORDINATION CENTER.) (RAIS)− A temporary service provided by facilities, which are not located on the landing airport, but have RCO− communication capability and automated weather (See REMOTE COMMUNICATIONS OUTLET.) reporting available to the pilot at the landing airport. RCR− REMOTE COMMUNICATIONS AIR/GROUND (See RUNWAY CONDITION READING.) FACILITY− An unmanned VHF/UHF transmitter/ READ BACK− Repeat my message back to me. receiver facility which is used to expand ARTCC air/ground communications coverage and to facilitate RECEIVER AUTONOMOUS INTEGRITY MON- direct contact between pilots and controllers. RCAG ITORING (RAIM)− A technique whereby a civil facilities are sometimes not equipped with emergen- GNSS receiver/processor determines the integrity of cy frequencies 121.5 MHz and 243.0 MHz. the GNSS navigation signals without reference to (Refer to AIM.) sensors or non-DoD integrity systems other than the receiver itself. This determination is achieved by a REMOTE COMMUNICATIONS OUTLET consistency check among redundant pseudorange (RCO)− An unmanned communications facility measurements. remotely controlled by air traffic personnel. RCOs serve FSSs. Remote Transmitter/Receivers (RTR) RECEIVING CONTROLLER− A controller/facility serve terminal ATC facilities. An RCO or RTR may receiving control of an aircraft from another be UHF or VHF and will extend the communication controller/facility. range of the air traffic facility. There are several classes of RCOs and RTRs. The class is determined RECEIVING FACILITY− by the number of transmitters or receivers. Classes A (See RECEIVING CONTROLLER.) through G are used primarily for air/ground purposes. RECONFORMANCE− The automated process of RCO and RTR class O facilities are nonprotected bringing an aircraft’s Current Plan Trajectory into outlets subject to undetected and prolonged outages. conformance with its track. RCO (O’s) and RTR (O’s) were established for the express purpose of providing ground-to-ground REDUCE SPEED TO (SPEED)− communications between air traffic control special- (See SPEED ADJUSTMENT.) ists and pilots located at a satellite airport for delivering en route clearances, issuing departure REFINED HAZARD AREA (RHA)− Used by ATC. authorizations, and acknowledging instrument flight Airspace that is defined and distributed after a failure rules cancellations or departure/landing times. As a of a launch or reentry operation to provide a more secondary function, they may be used for advisory concise depiction of the hazard location than a purposes whenever the aircraft is below the coverage Contingency Hazard Area. of the primary air/ground frequency. (See AIRCRAFT HAZARD AREA.) (See CONTINGENCY HAZARD AREA.) REMOTE PILOT IN COMMAND (RPIC)− The (See TRANSITIONAL HAZARD AREA.) RPIC is directly responsible for and is the final authority as to the operation of the unmanned aircraft REIL− system. (See RUNWAY END IDENTIFIER LIGHTS.) REMOTE TRANSMITTER/RECEIVER (RTR)− RELEASE TIME− A departure time restriction (See REMOTE COMMUNICATIONS OUTLET.) issued to a pilot by ATC (either directly or through an authorized relay) when necessary to separate a REPORT− Used to instruct pilots to advise ATC of departing aircraft from other traffic. specified information; e.g., “Report passing Hamil- (See ICAO term RELEASE TIME.) ton VOR.”

PCG R−4 6/17/21 Pilot/Controller Glossary

REPORTING POINT− A geographical location in displays, and provides lateral guidance to a profile or relation to which the position of an aircraft is path. reported. g. Vertical Navigation (VNAV). A function of area (See COMPULSORY REPORTING POINTS.) navigation (RNAV) equipment which calculates, (See ICAO term REPORTING POINT.) displays, and provides vertical guidance to a profile (Refer to AIM.) or path. REPORTING POINT [ICAO]− A specified geo- RESCUE COORDINATION CENTER (RCC)− A graphical location in relation to which the position of search and rescue (SAR) facility equipped and an aircraft can be reported. manned to coordinate and control SAR operations in an area designated by the SAR plan. The U.S. Coast REQUEST FULL ROUTE CLEARANCE− Used Guard and the U.S. Air Force have responsibility for by pilots to request that the entire route of flight be the operation of RCCs. read verbatim in an ATC clearance. Such request should be made to preclude receiving an ATC (See ICAO term RESCUE CO-ORDINATION CENTRE.) clearance based on the original filed flight plan when a filed IFR flight plan has been revised by the pilot, RESCUE CO-ORDINATION CENTRE [ICAO]− A company, or operations prior to departure. unit responsible for promoting efficient organization of search and rescue service and for coordinating the REQUIRED NAVIGATION PERFORMANCE conduct of search and rescue operations within a (RNP)– A statement of the navigational performance search and rescue region. necessary for operation within a defined airspace. The following terms are commonly associated with RESOLUTION ADVISORY− A display indication RNP: given to the pilot by the Traffic alert and Collision a. Required Navigation Performance Level or Avoidance System (TCAS II) recommending a Type (RNP-X). A value, in nautical miles (NM), from maneuver to increase vertical separation relative to an the intended horizontal position within which an intruding aircraft. Positive, negative, and vertical aircraft would be at least 95-percent of the total flying speed limit (VSL) advisories constitute the resolution time. advisories. A resolution advisory is also classified as corrective or preventive. b. Advanced − Required Navigation Performance (A−RNP). A navigation specification based on RNP RESTRICTED AREA− that requires advanced functions such as scalable (See SPECIAL USE AIRSPACE.) RNP, radius−to−fix (RF) legs, and tactical parallel (See ICAO term RESTRICTED AREA.) offsets. This sophisticated Navigation Specification (NavSpec) is designated by the abbreviation RESTRICTED AREA [ICAO]− An airspace of “A−RNP”. defined dimensions, above the land areas or territorial c. Required Navigation Performance (RNP) waters of a State, within which the flight of aircraft Airspace. A generic term designating airspace, is restricted in accordance with certain specified route(s), leg(s), operation(s), or procedure(s) where conditions. minimum required navigational performance (RNP) RESUME NORMAL SPEED− Used by ATC to have been established. advise a pilot to resume an aircraft’s normal operating d. Actual Navigation Performance (ANP). A speed. It is issued to terminate a speed adjustment measure of the current estimated navigational where no published speed restrictions apply. It does performance. Also referred to as Estimated Position not delete speed restrictions in published procedures Error (EPE). of upcoming segments of flight. This does not relieve e. Estimated Position Error (EPE). A measure of the pilot of those speed restrictions that are applicable the current estimated navigational performance. Also to 14 CFR Section 91.117. referred to as Actual Navigation Performance (ANP). RESUME OWN NAVIGATION− Used by ATC to f. Lateral Navigation (LNAV). A function of area advise a pilot to resume his/her own navigational navigation (RNAV) equipment which calculates, responsibility. It is issued after completion of a radar

PCG R−5 Pilot/Controller Glossary 6/17/21

vector or when radar contact is lost while the aircraft ROUTE− A defined path, consisting of one or more is being radar vectored. courses in a horizontal plane, which aircraft traverse (See RADAR CONTACT LOST.) over the surface of the earth. (See RADAR SERVICE TERMINATED.) (See AIRWAY.) (See JET ROUTE.) RESUME PUBLISHED SPEED− Used by ATC to (See PUBLISHED ROUTE.) advise a pilot to resume published speed restrictions (See UNPUBLISHED ROUTE.) that are applicable to a SID, STAR, or other ROUTE ACTION NOTIFICATION− EDST notifi- instrument procedure. It is issued to terminate a speed cation that a PAR/PDR/PDAR has been applied to the adjustment where speed restrictions are published on flight plan. a charted procedure. (See ATC PREFERRED ROUTE RHA− NOTIFICATION.) (See EN ROUTE DECISION SUPPORT TOOL.) (See REFINED HAZARD AREA.) ROUTE SEGMENT− As used in Air Traffic Control, RMI− a part of a route that can be defined by two (See RADIO MAGNETIC INDICATOR.) navigational fixes, two NAVAIDs, or a fix and a NAVAID. RNAV− (See FIX.) (See AREA NAVIGATION (RNAV).) (See ROUTE.) (See ICAO term ROUTE SEGMENT.) RNAV APPROACH− An instrument approach procedure which relies on aircraft area navigation ROUTE SEGMENT [ICAO]− A portion of a route to equipment for navigational guidance. be flown, as defined by two consecutive significant points specified in a flight plan. (See AREA NAVIGATION (RNAV).) (See INSTRUMENT APPROACH RPIC− PROCEDURE.) (See REMOTE PILOT IN COMMAND.) RSA− ROAD RECONNAISSANCE (RC)− Military activ- (See RUNWAY SAFETY AREA.) ity requiring navigation along roads, railroads, and rivers. Reconnaissance route/route segments are RTR− seldom along a straight line and normally require a (See REMOTE TRANSMITTER/RECEIVER.) lateral route width of 10 NM to 30 NM and an altitude RUNWAY− A defined rectangular area on a land range of 500 feet to 10,000 feet AGL. airport prepared for the landing and takeoff run of aircraft along its length. Runways are normally ROGER− I have received all of your last numbered in relation to their magnetic direction transmission. It should not be used to answer a rounded off to the nearest 10 degrees; e.g., Runway question requiring a yes or a no answer. 1, Runway 25. (See AFFIRMATIVE.) (See PARALLEL RUNWAYS.) (See NEGATIVE.) (See ICAO term RUNWAY.) ROLLOUT RVR− RUNWAY [ICAO]− A defined rectangular area on a (See VISIBILITY.) land aerodrome prepared for the landing and takeoff of aircraft. ROTOR WASH− A phenomenon resulting from the RUNWAY CENTERLINE LIGHTING− vertical down wash of air generated by the main (See AIRPORT LIGHTING.) rotor(s) of a helicopter. RUNWAY CONDITION CODES (RwyCC)− Nu- ROUND−ROBIN FLIGHT PLAN− A single flight merical readings, provided by airport operators, that plan filed from the departure airport to an indicate runway surface contamination (for example, intermediary destination(s) and then returning to the slush, ice, rain, etc.). These values range from “1” original departure airport. (poor) to “6” (dry) and must be included on the ATIS

PCG R−6 6/17/21 Pilot/Controller Glossary

when the reportable condition is less than 6 in any one determined by the runway configuration for arrival or more of the three runway zones (touchdown, metering processing purposes. midpoint, rollout). RUNWAY LIGHTS− RUNWAY CONDITION READING− Numerical (See AIRPORT LIGHTING.) decelerometer readings relayed by air traffic controllers at USAF and certain civil bases for use by RUNWAY MARKINGS− the pilot in determining runway braking action. (See AIRPORT MARKING AIDS.) These readings are routinely relayed only to USAF RUNWAY OVERRUN− In military aviation exclu- and Air National Guard Aircraft. sively, a stabilized or paved area beyond the end of a (See BRAKING ACTION.) runway, of the same width as the runway plus RUNWAY CONDITION REPORT (RwyCR)− A shoulders, centered on the extended runway data collection worksheet used by airport operators centerline. that correlates the runway percentage of coverage RUNWAY PROFILE DESCENT− An instrument along with the depth and type of contaminant for the flight rules (IFR) air traffic control arrival procedure purpose of creating a FICON NOTAM. to a runway published for pilot use in graphic and/or (See RUNWAY CONDITION CODES.) textual form and may be associated with a STAR. RUNWAY END IDENTIFIER LIGHTS (REIL)− Runway Profile Descents provide routing and may depict crossing altitudes, speed restrictions, and (See AIRPORT LIGHTING.) headings to be flown from the en route structure to the RUNWAY ENTRANCE LIGHTS (REL)−An array point where the pilot will receive clearance for and of red lights which include the first light at the hold execute an instrument approach procedure. A line followed by a series of evenly spaced lights to the Runway Profile Descent may apply to more than one runway edge aligned with the taxiway centerline, and runway if so stated on the chart. one additional light at the runway centerline in line (Refer to AIM.) with the last two lights before the runway edge. RUNWAY SAFETY AREA− A defined surface RUNWAY GRADIENT− The average slope, mea- surrounding the runway prepared, or suitable, for sured in percent, between two ends or points on a reducing the risk of damage to airplanes in the event runway. Runway gradient is depicted on Government of an undershoot, overshoot, or excursion from the aerodrome sketches when total runway gradient runway. The dimensions of the RSA vary and can be exceeds 0.3%. determined by using the criteria contained within AC 150/5300-13, Airport Design, Chapter 3. RUNWAY HEADING− The magnetic direction that Figure 3−1 in AC 150/5300-13 depicts the RSA. The corresponds with the runway centerline extended, not design standards dictate that the RSA shall be: the painted runway number. When cleared to “fly or maintain runway heading,” pilots are expected to fly a. Cleared, graded, and have no potentially or maintain the heading that corresponds with the hazardous ruts, humps, depressions, or other surface extended centerline of the departure runway. Drift variations; correction shall not be applied; e.g., Runway 4, actual b. Drained by grading or storm sewers to prevent magnetic heading of the runway centerline 044, fly water accumulation; 044. c. Capable, under dry conditions, of supporting RUNWAY IN USE/ACTIVE RUNWAY/DUTY snow removal equipment, aircraft rescue and RUNWAY− Any runway or runways currently being firefighting equipment, and the occasional passage of used for takeoff or landing. When multiple runways aircraft without causing structural damage to the are used, they are all considered active runways. In aircraft; and, the metering sense, a selectable adapted item which d. Free of objects, except for objects that need to specifies the landing runway configuration or be located in the runway safety area because of their direction of traffic flow. The adapted optimum flight function. These objects shall be constructed on low plan from each transition fix to the vertex is impact resistant supports (frangible mounted struc-

PCG R−7 Pilot/Controller Glossary 6/17/21

tures) to the lowest practical height with the frangible aircraft less than 12,500 pounds are included only if point no higher than 3 inches above grade. the airport proprietor determines that the aircraft (Refer to AC 150/5300-13, Airport Design, creates a noise problem. Runway use programs are Chapter 3.) coordinated with FAA offices, and safety criteria RUNWAY STATUS LIGHTS (RWSL) SYSTEM− used in these programs are developed by the Office of The RWSL is a system of runway and taxiway Flight Operations. Runway use programs are lighting to provide pilots increased situational administered by the Air Traffic Service as “Formal” awareness by illuminating runway entry lights (REL) or “Informal” programs. when the runway is unsafe for entry or crossing, and a. Formal Runway Use Program− An approved take-off hold lights (THL) when the runway is unsafe noise abatement program which is defined and for departure. acknowledged in a Letter of Understanding between Flight Operations, Air Traffic Service, the airport RUNWAY TRANSITION− proprietor, and the users. Once established, participa- a. Conventional STARs/SIDs. The portion of a tion in the program is mandatory for aircraft operators STAR/SID that serves a particular runway or and pilots as provided for in 14 CFR Section 91.129. runways at an airport. b. Informal Runway Use Program− An approved b. RNAV STARs/SIDs. Defines a path(s) from noise abatement program which does not require a the common route to the final point(s) on a STAR. For Letter of Understanding, and participation in the a SID, the common route that serves a particular program is voluntary for aircraft operators/pilots. runway or runways at an airport. RUNWAY VISUAL RANGE (RVR)− RUNWAY USE PROGRAM− A noise abatement (See VISIBILITY.) runway selection plan designed to enhance noise RwyCC− abatement efforts with regard to airport communities for arriving and departing aircraft. These plans are (See RUNWAY CONDITION CODES.) developed into runway use programs and apply to all RwyCR− turbojet aircraft 12,500 pounds or heavier; turbojet (See RUNWAY CONDITION REPORT.)

PCG R−8 6/17/21 Pilot/Controller Glossary S

SAA− or aircraft/other tangible object) that safety logic has (See SPECIAL ACTIVITY AIRSPACE.) predicted will result in an imminent collision, based upon the current set of Safety Logic parameters. SAFETY ALERT− A safety alert issued by ATC to b. FALSE ALERT− aircraft under their control if ATC is aware the aircraft is at an altitude which, in the controller’s judgment, 1. Alerts generated by one or more false places the aircraft in unsafe proximity to terrain, surface−radar targets that the system has interpreted obstructions, or other aircraft. The controller may as real tracks and placed into safety logic. discontinue the issuance of further alerts if the pilot 2. Alerts in which the safety logic software did advises he/she is taking action to correct the situation not perform correctly, based upon the design or has the other aircraft in sight. specifications and the current set of Safety Logic parameters. a. Terrain/Obstruction Alert− A safety alert issued by ATC to aircraft under their control if ATC is aware 3. The alert is generated by surface radar targets the aircraft is at an altitude which, in the controller’s caused by moderate or greater precipitation. judgment, places the aircraft in unsafe proximity to c. NUISANCE ALERT− An alert in which one or terrain/obstructions; e.g., “Low Altitude Alert, check more of the following is true: your altitude immediately.” 1. The alert is generated by a known situation b. Aircraft Conflict Alert− A safety alert issued by that is not considered an unsafe operation, such as ATC to aircraft under their control if ATC is aware of LAHSO or other approved operations. an aircraft that is not under their control at an altitude 2. The alert is generated by inaccurate secon- which, in the controller’s judgment, places both dary radar data received by the Safety Logic System. aircraft in unsafe proximity to each other. With the 3. One or more of the aircraft involved in the alert, ATC will offer the pilot an alternate course of alert is not intending to use a runway (for example, action when feasible; e.g., “Traffic Alert, advise you helicopter, pipeline patrol, non−Mode C overflight, turn right heading zero niner zero or climb to eight etc.). thousand immediately.” d. VALID NON−ALERT− A situation in which Note: The issuance of a safety alert is contingent the safety logic software correctly determines that an upon the capability of the controller to have an alert is not required, based upon the design awareness of an unsafe condition. The course of specifications and the current set of Safety Logic action provided will be predicated on other traffic parameters. under ATC control. Once the alert is issued, it is e. INVALID NON−ALERT− A situation in which solely the pilot’s prerogative to determine what course of action, if any, he/she will take. the safety logic software did not issue an alert when an alert was required, based upon the design SAFETY LOGIC SYSTEM− A software enhance- specifications. ment to ASDE−3, ASDE−X, and ASSC, that predicts SAIL BACK− A maneuver during high wind the path of aircraft landing and/or departing, and/or conditions (usually with power off) where float plane vehicular movements on runways. Visual and aural movement is controlled by water rudders/opening alarms are activated when the safety logic projects a and closing cabin doors. potential collision. The Airport Movement Area SAME DIRECTION AIRCRAFT− Aircraft are Safety System (AMASS) is a safety logic system operating in the same direction when: enhancement to the ASDE−3. The Safety Logic a. They are following the same track in the same System for ASDE−X and ASSC is an integral part of direction; or the software program. b. Their tracks are parallel and the aircraft are SAFETY LOGIC SYSTEM ALERTS− flying in the same direction; or a. ALERT− An actual situation involving two real c. Their tracks intersect at an angle of less than 45 safety logic tracks (aircraft/aircraft, aircraft/vehicle, degrees.

PCG S−1 Pilot/Controller Glossary 6/17/21

SAR− directly to the Rescue Coordination Center by (See SEARCH AND RESCUE.) telephone. (See FLIGHT SERVICE STATION.) SATELLITE−BASED AUGMENTATION SYS- (See RESCUE COORDINATION CENTER.) TEM (SBAS) − A wide coverage augmentation (Refer to AIM.) system in which the user receives augmentation SEARCH AND RESCUE FACILITY− A facility information from a satellite−based transmitter. responsible for maintaining and operating a search (See WIDE−AREA AUGMENTATION SYSTEM and rescue (SAR) service to render aid to persons and (WAAS.) property in distress. It is any SAR unit, station, NET, or other operational activity which can be usefully SAY AGAIN− Used to request a repeat of the last employed during an SAR Mission; e.g., a Civil Air transmission. Usually specifies transmission or Patrol Wing, or a Coast Guard Station. portion thereof not understood or received; e.g., “Say (See SEARCH AND RESCUE.) again all after ABRAM VOR.” SECNOT− SAY ALTITUDE− Used by ATC to ascertain an (See SECURITY NOTICE.) aircraft’s specific altitude/flight level. When the SECONDARY RADAR TARGET− A target derived aircraft is climbing or descending, the pilot should from a transponder return presented on a radar state the indicated altitude rounded to the nearest 100 display. feet. SECTIONAL AERONAUTICAL CHARTS− (See AERONAUTICAL CHART.) SAY HEADING− Used by ATC to request an aircraft heading. The pilot should state the actual heading of SECTOR LIST DROP INTERVAL− A parameter the aircraft. number of minutes after the meter fix time when arrival aircraft will be deleted from the arrival sector SCHEDULED TIME OF ARRIVAL (STA)− A STA list. is the desired time that an aircraft should cross a SECURITY NOTICE (SECNOT) − A SECNOT is a certain point (landing or metering fix). It takes other request originated by the Air Traffic Security traffic and airspace configuration into account. A Coordinator (ATSC) for an extensive communica- STA time shows the results of the TBFM scheduler tions search for aircraft involved, or suspected of that has calculated an arrival time according to being involved, in a security violation, or are parameters such as optimized spacing, aircraft considered a security risk. A SECNOT will include performance, and weather. the aircraft identification, search area, and expiration time. The search area, as defined by the ATSC, could SDF− be a single airport, multiple airports, a radius of an (See SIMPLIFIED DIRECTIONAL FACILITY.) airport or fix, or a route of flight. Once the expiration time has been reached, the SECNOT is considered to SEA LANE− A designated portion of water outlined be canceled. by visual surface markers for and intended to be used SECURITY SERVICES AIRSPACE − Areas by aircraft designed to operate on water. established through the regulatory process or by NOTAM, issued by the Administrator under title 14, SEARCH AND RESCUE− A service which seeks CFR, sections 99.7, 91.141, and 91.139, which missing aircraft and assists those found to be in need specify that ATC security services are required; i.e., of assistance. It is a cooperative effort using the ADIZ or temporary flight rules areas. facilities and services of available Federal, state and local agencies. The U.S. Coast Guard is responsible SEE AND AVOID− When weather conditions for coordination of search and rescue for the Maritime permit, pilots operating IFR or VFR are required to Region, and the U.S. Air Force is responsible for observe and maneuver to avoid other aircraft. search and rescue for the Inland Region. Information Right-of-way rules are contained in 14 CFR Part 91. pertinent to search and rescue should be passed SEGMENTED CIRCLE− A system of visual through any air traffic facility or be transmitted indicators designed to provide traffic pattern

PCG S−2 6/17/21 Pilot/Controller Glossary

information at airports without operating control SERVICE− A generic term that designates functions towers. or assistance available from or rendered by air traffic (Refer to AIM.) control. For example, Class C service would denote the ATC services provided within a Class C airspace SEGMENTS OF AN INSTRUMENT APPROACH area. PROCEDURE− An instrument approach procedure may have as many as four separate segments SEVERE WEATHER AVOIDANCE PLAN depending on how the approach procedure is (SWAP)− An approved plan to minimize the affect of structured. severe weather on traffic flows in impacted terminal and/or ARTCC areas. A SWAP is normally a. Initial Approach− The segment between the implemented to provide the least disruption to the initial approach fix and the intermediate fix or the ATC system when flight through portions of airspace point where the aircraft is established on the is difficult or impossible due to severe weather. intermediate course or final approach course. (See ICAO term INITIAL APPROACH SEVERE WEATHER FORECAST ALERTS− SEGMENT.) Preliminary messages issued in order to alert users b. Intermediate Approach− The segment between that a Severe Weather Watch Bulletin (WW) is being the intermediate fix or point and the final approach issued. These messages define areas of possible fix. severe thunderstorms or tornado activity. The messages are unscheduled and issued as required by (See ICAO term INTERMEDIATE APPROACH SEGMENT.) the Storm Prediction Center (SPC) at Norman, Oklahoma. c. Final Approach− The segment between the final (See AIRMET.) approach fix or point and the runway, airport, or (See CONVECTIVE SIGMET.) missed approach point. (See CWA.) (See ICAO term FINAL APPROACH SEGMENT.) (See SIGMET.) d. Missed Approach− The segment between the SFA− missed approach point or the point of arrival at (See SINGLE FREQUENCY APPROACH.) decision height and the missed approach fix at the prescribed altitude. SFO− (Refer to 14 CFR Part 97.) (See SIMULATED FLAMEOUT.) (See ICAO term MISSED APPROACH SHF− PROCEDURE.) (See SUPER HIGH FREQUENCY.) SELF−BRIEFING− A self−briefing is a review, SHORT RANGE CLEARANCE− A clearance using automated tools, of all meteorological and issued to a departing IFR flight which authorizes IFR aeronautical information that may influence the pilot flight to a specific fix short of the destination while in planning, altering, or canceling a proposed route of air traffic control facilities are coordinating and flight. obtaining the complete clearance. SEPARATION− In air traffic control, the spacing of SHORT TAKEOFF AND LANDING AIRCRAFT aircraft to achieve their safe and orderly movement in (STOL)− An aircraft which, at some weight within its flight and while landing and taking off. approved operating weight, is capable of operating (See SEPARATION MINIMA.) from a runway in compliance with the applicable (See ICAO term SEPARATION.) STOL characteristics, airworthiness, operations, noise, and pollution standards. SEPARATION [ICAO]− Spacing between aircraft, (See VERTICAL TAKEOFF AND LANDING levels or tracks. AIRCRAFT.) SEPARATION MINIMA− The minimum longitudi- SIAP− nal, lateral, or vertical distances by which aircraft are (See STANDARD INSTRUMENT APPROACH spaced through the application of air traffic control PROCEDURE.) procedures. SID− (See SEPARATION.) (See STANDARD INSTRUMENT DEPARTURE.)

PCG S−3 Pilot/Controller Glossary 6/17/21

SIDESTEP MANEUVER− A visual maneuver SIMULTANEOUS CLOSE PARALLEL AP- accomplished by a pilot at the completion of an PROACHES− A simultaneous, independent instrument approach to permit a straight-in landing approach operation permitting ILS/RNAV/GLS on a parallel runway not more than 1,200 feet to either approaches to airports having parallel runways side of the runway to which the instrument approach separated by at least 3,000 feet and less than was conducted. 4,300−feet between centerlines. Aircraft are permit- (Refer to AIM.) ted to pass each other during these simultaneous operations. Integral parts of a total system are radar, SIGMET− A weather advisory issued concerning NTZ monitoring with enhanced FMA color displays weather significant to the safety of all aircraft. that include aural and visual alerts and predictive SIGMET advisories cover severe and extreme aircraft position software, communications override, turbulence, severe icing, and widespread dust or ATC procedures, an Attention All Users Page sandstorms that reduce visibility to less than 3 miles. (AAUP), PRM in the approach name, and (See AIRMET.) appropriate ground based and airborne equipment. (See AWW.) High update rate surveillance sensor required for (See CONVECTIVE SIGMET.) certain runway or approach course separations. (See CWA.) (See ICAO term SIGMET INFORMATION.) SIMULTANEOUS (CONVERGING) DEPEND- (Refer to AIM.) ENT APPROACHES- An approach operation permitting ILS/RNAV/GLS approaches to runways SIGMET INFORMATION [ICAO]− Information or missed approach courses that intersect where issued by a meteorological watch office concerning required minimum spacing between the aircraft on the occurrence or expected occurrence of specified each final approach course is required. en-route weather phenomena which may affect the SIMULTANEOUS (CONVERGING) INDEPEND- safety of aircraft operations. ENT APPROACHES- An approach operation SIGNIFICANT METEOROLOGICAL INFOR- permitting ILS/RNAV/GLS approaches to non-par- MATION− allel runways where approach procedure design (See SIGMET.) maintains the required aircraft spacing throughout the approach and missed approach and hence the SIGNIFICANT POINT− A point, whether a named operations may be conducted independently. intersection, a NAVAID, a fix derived from a NAVAID(s), or geographical coordinate expressed in SIMULTANEOUS ILS APPROACHES− An degrees of latitude and longitude, which is approach system permitting simultaneous ILS established for the purpose of providing separation, approaches to airports having parallel runways as a reporting point, or to delineate a route of flight. separated by at least 4,300 feet between centerlines. Integral parts of a total system are ILS, radar, SIMPLIFIED DIRECTIONAL FACILITY (SDF)− communications, ATC procedures, and appropriate A NAVAID used for nonprecision instrument airborne equipment. approaches. The final approach course is similar to (See PARALLEL RUNWAYS.) that of an ILS localizer except that the SDF course (Refer to AIM.) may be offset from the runway, generally not more SIMULTANEOUS OFFSET INSTRUMENT than 3 degrees, and the course may be wider than the APPROACH (SOIA)− An instrument landing localizer, resulting in a lower degree of accuracy. system comprised of an ILS PRM, RNAV PRM or (Refer to AIM.) GLS PRM approach to one runway and an offset SIMULATED FLAMEOUT− A practice approach LDA PRM with glideslope or an RNAV PRM or by a jet aircraft (normally military) at idle thrust to a GLS PRM approach utilizing vertical guidance to runway. The approach may start at a runway (high another where parallel runway spaced less than 3,000 key) and may continue on a relatively high and wide feet and at least 750 feet apart. The approach courses downwind leg with a continuous turn to final. It converge by 2.5 to 3 degrees. Simultaneous close terminates in landing or low approach. The purpose parallel PRM approach procedures apply up to the of this approach is to simulate a flameout. point where the approach course separation becomes (See FLAMEOUT.) 3,000 feet, at the offset MAP. From the offset MAP

PCG S−4 6/17/21 Pilot/Controller Glossary

to the runway threshold, visual separation by the SLOW TAXI− To taxi a float plane at low power or aircraft conducting the offset approach is utilized. low RPM. (Refer to AIM) SMALL UNMANNED AIRCRAFT SYSTEM SIMULTANEOUS (PARALLEL) DEPENDENT (sUAS)– An unmanned aircraft weighing less than 55 APPROACHES- An approach operation permitting pounds on takeoff, including everything that is on ILS/RNAV/GLS approaches to adjacent parallel board or otherwise attached to the aircraft. runways where prescribed diagonal spacing must be SN− maintained. Aircraft are not permitted to pass each other during simultaneous dependent operations. (See SYSTEM STRATEGIC NAVIGATION.) Integral parts of a total system ATC procedures, and SPACE−BASED ADS−B (SBA)− A constellation of appropriate airborne and ground based equipment. satellites that receives ADS−B Out broadcasts and relays that information to the appropriate surveil- SINGLE DIRECTION ROUTES− Preferred IFR lance facility. The currently deployed SBA system is Routes which are sometimes depicted on high only capable of receiving broadcasts from 1090ES− altitude en route charts and which are normally flown equipped aircraft, and not from those equipped with in one direction only. only a universal access transceiver (UAT). Also, (See PREFERRED IFR ROUTES.) aircraft with a top−of−fuselage−mounted transponder (Refer to CHART SUPPLEMENT U.S.) antenna (required for TCAS II installations) will be SINGLE FREQUENCY APPROACH− A service better received by SBA, especially at latitudes below provided under a letter of agreement to military 45 degrees. single-piloted turbojet aircraft which permits use of (See AUTOMATIC DEPENDENT a single UHF frequency during approach for landing. SURVEILLANCE−BROADCAST.) Pilots will not normally be required to change (See AUTOMATIC DEPENDENT frequency from the beginning of the approach to SURVEILLANCE−BROADCAST OUT.) touchdown except that pilots conducting an en route SPEAK SLOWER− Used in verbal communications descent are required to change frequency when as a request to reduce speech rate. control is transferred from the air route traffic control center to the terminal facility. The abbreviation SPECIAL ACTIVITY AIRSPACE (SAA)− Any “SFA” in the DOD FLIP IFR Supplement under airspace with defined dimensions within the National “Communications” indicates this service is available Airspace System wherein limitations may be at an aerodrome. imposed upon aircraft operations. This airspace may be restricted areas, prohibited areas, military SINGLE-PILOTED AIRCRAFT− A military operations areas, air ATC assigned airspace, and any turbojet aircraft possessing one set of flight controls, other designated airspace areas. The dimensions of tandem cockpits, or two sets of flight controls but this airspace are programmed into EDST and can be operated by one pilot is considered single-piloted by designated as either active or inactive by screen entry. ATC when determining the appropriate air traffic Aircraft trajectories are constantly tested against the service to be applied. dimensions of active areas and alerts issued to the (See SINGLE FREQUENCY APPROACH.) applicable sectors when violations are predicted. SKYSPOTTER− A pilot who has received (See EN ROUTE DECISION SUPPORT TOOL.) specialized training in observing and reporting SPECIAL AIR TRAFFIC RULES (SATR)− Rules inflight weather phenomena. that govern procedures for conducting flights in SLASH− A radar beacon reply displayed as an certain areas listed in 14 CFR Part 93. The term elongated target. “SATR” is used in the United States to describe the rules for operations in specific areas designated in the SLDI− Code of Federal Regulations. (See SECTOR LIST DROP INTERVAL.) (Refer to 14 CFR Part 93.) SLOT TIME− SPECIAL EMERGENCY− A condition of air piracy (See METER FIX TIME/SLOT TIME.) or other hostile act by a person(s) aboard an aircraft

PCG S−5 Pilot/Controller Glossary 6/17/21

which threatens the safety of the aircraft or its an aircraft without the permission of the using passengers. agency. (Refer to AIM.) SPECIAL FLIGHT RULES AREA (SFRA)− An (Refer to En Route Charts.) area in the NAS, described in 14 CFR Part 93, e. Restricted Area− Permanent and temporary wherein the flight of aircraft is subject to special restricted areas are airspace designated under 14 CFR traffic rules, unless otherwise authorized by air traffic Part 73, within which the flight of aircraft, while not control. Not all areas listed in 14 CFR Part 93 are wholly prohibited, is subject to restriction. Most designated SFRA, but special air traffic rules apply to restricted areas are designated joint use and IFR/VFR all areas described in 14 CFR Part 93. operations in the area may be authorized by the controlling ATC facility when it is not being utilized SPECIAL INSTRUMENT APPROACH PROCE- by the using agency. Permanent restricted areas are DURE− depicted on Sectional Aeronautical, VFR Terminal (See INSTRUMENT APPROACH PROCEDURE.) Area, and applicable En Route charts. Where joint use is authorized, the name of the ATC controlling SPECIAL USE AIRSPACE− Airspace of defined facility is also shown. dimensions identified by an area on the surface of the Note: Temporary restricted areas are not charted. earth wherein activities must be confined because of (Refer to 14 CFR Part 73.) their nature and/or wherein limitations may be (Refer to AIM.) imposed upon aircraft operations that are not a part of those activities. Types of special use airspace are: f. Warning Area− A warning area is airspace of defined dimensions extending from 3 nautical miles a. Alert Area− Airspace which may contain a high outward from the coast of the United States, that volume of pilot training activities or an unusual type contains activity that may be hazardous to of aerial activity, neither of which is hazardous to nonparticipating aircraft. The purpose of such aircraft. Alert Areas are depicted on aeronautical warning area is to warn nonparticipating pilots of the charts for the information of nonparticipating pilots. potential danger. A warning area may be located over All activities within an Alert Area are conducted in domestic or international waters or both. accordance with Federal Aviation Regulations, and pilots of participating aircraft as well as pilots SPECIAL VFR CONDITIONS− Meteorological transiting the area are equally responsible for conditions that are less than those required for basic collision avoidance. VFR flight in Class B, C, D, or E surface areas and in which some aircraft are permitted flight under b. Controlled Firing Area− Airspace wherein visual flight rules. activities are conducted under conditions so (See SPECIAL VFR OPERATIONS.) controlled as to eliminate hazards to nonparticipating (Refer to 14 CFR Part 91.) aircraft and to ensure the safety of persons and property on the ground. SPECIAL VFR FLIGHT [ICAO]− A VFR flight cleared by air traffic control to operate within Class c. Military Operations Area (MOA)− Permanent B, C, D, and E surface areas in meteorological and temporary MOAs are airspace established conditions below VMC. outside of Class A airspace area to separate or segregate certain nonhazardous military activities SPECIAL VFR OPERATIONS− Aircraft operating from IFR traffic and to identify for VFR traffic where in accordance with clearances within Class B, C, D, these activities are conducted. Permanent MOAs are and E surface areas in weather conditions less than the depicted on Sectional Aeronautical, VFR Terminal basic VFR weather minima. Such operations must be Area, and applicable En Route Low Altitude Charts. requested by the pilot and approved by ATC. (See SPECIAL VFR CONDITIONS.) Note: Temporary MOAs are not charted. (See ICAO term SPECIAL VFR FLIGHT.) (Refer to AIM.) SPEED− d. Prohibited Area− Airspace designated under (See AIRSPEED.) 14 CFR Part 73 within which no person may operate (See GROUND SPEED.)

PCG S−6 6/17/21 Pilot/Controller Glossary

SPEED ADJUSTMENT− An ATC procedure used to STANDARD INSTRUMENT APPROACH PRO- request pilots to adjust aircraft speed to a specific CEDURE (SIAP)− value for the purpose of providing desired spacing. (See INSTRUMENT APPROACH PROCEDURE.) Pilots are expected to maintain a speed of plus or STANDARD INSTRUMENT DEPARTURE (SID)− minus 10 knots or 0.02 Mach number of the specified A preplanned instrument flight rule (IFR) air traffic speed. Examples of speed adjustments are: control (ATC) departure procedure printed for a. “Increase/reduce speed to Mach point pilot/controller use in graphic form to provide (number).” obstacle clearance and a transition from the terminal b. “Increase/reduce speed to (speed in knots)” or area to the appropriate en route structure. SIDs are “Increase/reduce speed (number of knots) knots.” primarily designed for system enhancement to expedite traffic flow and to reduce pilot/controller SPEED BRAKES− Moveable aerodynamic devices workload. ATC clearance must always be received on aircraft that reduce airspeed during descent and prior to flying a SID. landing. (See IFR TAKEOFF MINIMUMS AND SPEED SEGMENTS− Portions of the arrival route DEPARTURE PROCEDURES.) between the transition point and the vertex along the (See OBSTACLE DEPARTURE PROCEDURE.) optimum flight path for which speeds and altitudes (Refer to AIM.) are specified. There is one set of arrival speed STANDARD RATE TURN− A turn of three degrees segments adapted from each transition point to each per second. vertex. Each set may contain up to six segments. STANDARD TERMINAL ARRIVAL (STAR)− A SPOOFING− Denotes emissions of GNSS−like preplanned instrument flight rule (IFR) air traffic signals that may be acquired and tracked in control arrival procedure published for pilot use in combination with or instead of the intended signals graphic and/or textual form. STARs provide by civil receivers. The onset of spoofing effects can transition from the en route structure to an outer fix be instantaneous or delayed, and effects can persist or an instrument approach fix/arrival waypoint in the after the spoofing has ended. Spoofing can result in terminal area. false and potentially confusing, or hazardously misleading, position, navigation, and/or date/time STANDARD TERMINAL ARRIVAL CHARTS− information in addition to loss of GNSS use. (See AERONAUTICAL CHART.) SQUAWK (Mode, Code, Function)− Used by ATC STANDARD TERMINAL AUTOMATION RE- to instruct a pilot to activate the aircraft transponder PLACEMENT SYSTEM (STARS)− and ADS−B Out with altitude reporting enabled, or (See DTAS.) (military) to activate only specific modes, codes, or STAR− functions. Examples: “Squawk five seven zero (See STANDARD TERMINAL ARRIVAL.) seven;” “Squawk three/alpha, two one zero five.” (See TRANSPONDER.) STATE AIRCRAFT− Aircraft used in military, customs and police service, in the exclusive service STA− of any government or of any political subdivision (See SCHEDULED TIME OF ARRIVAL.) thereof, including the government of any state, STAGING/QUEUING− The placement, integration, territory, or possession of the United States or the and segregation of departure aircraft in designated District of Columbia, but not including any movement areas of an airport by departure fix, EDCT, government-owned aircraft engaged in carrying and/or restriction. persons or property for commercial purposes. STATIC RESTRICTIONS− Those restrictions that STAND BY− Means the controller or pilot must are usually not subject to change, fixed, in place, pause for a few seconds, usually to attend to other and/or published. duties of a higher priority. Also means to wait as in “stand by for clearance.” The caller should STATIONARY ALTITUDE RESERVATION reestablish contact if a delay is lengthy. “Stand by” is (STATIONARY ALTRV)– An altitude reservation not an approval or denial. which encompasses activities in a fixed area.

PCG S−7 Pilot/Controller Glossary 6/17/21

Stationary ALTRVs may include activities such as transmissions, or to turn off only specified functions special tests of weapons systems or equipment; of the aircraft transponder (military). certain U.S. Navy carrier, fleet, and anti−submarine (See STOP ALTITUDE SQUAWK.) operations; rocket, missile, and drone operations; and (See TRANSPONDER.) certain aerial refueling or similar operations. STOP STREAM− Used by ATC to request a pilot to STEP TAXI− To taxi a float plane at full power or suspend electronic attack activity. high RPM. (See JAMMING.) STEP TURN− A maneuver used to put a float plane STOPOVER FLIGHT PLAN− A flight plan format in a planing configuration prior to entering an active which permits in a single submission the filing of a sea lane for takeoff. The STEP TURN maneuver sequence of flight plans through interim full-stop should only be used upon pilot request. destinations to a final destination. STEPDOWN FIX− A fix permitting additional STOPWAY− An area beyond the takeoff runway no descent within a segment of an instrument approach less wide than the runway and centered upon the procedure by identifying a point at which a extended centerline of the runway, able to support the controlling obstacle has been safely overflown. airplane during an aborted takeoff, without causing STEREO ROUTE− A routinely used route of flight structural damage to the airplane, and designated by established by users and ARTCCs identified by a the airport authorities for use in decelerating the coded name; e.g., ALPHA 2. These routes minimize airplane during an aborted takeoff. flight plan handling and communications. STRAIGHT-IN APPROACH IFR− An instrument STNR ALT RESERVATION– An abbreviation for approach wherein final approach is begun without Stationary Altitude Reservation commonly used in first having executed a procedure turn, not NOTAMs. necessarily completed with a straight-in landing or (See STATIONARY ALTITUDE RESERVATION.) made to straight-in landing minimums. (See LANDING MINIMUMS.) STOL AIRCRAFT− (See STRAIGHT-IN APPROACH VFR.) (See SHORT TAKEOFF AND LANDING (See STRAIGHT-IN LANDING.) AIRCRAFT.) STRAIGHT-IN APPROACH VFR− Entry into the STOP ALTITUDE SQUAWK− Used by ATC to traffic pattern by interception of the extended runway instruct a pilot to turn off the automatic altitude centerline (final approach course) without executing reporting feature of the aircraft transponder and any other portion of the traffic pattern. ADS−B Out. It is issued when a verbally reported (See TRAFFIC PATTERN.) altitude varies by 300 feet or more from the automatic altitude report. STRAIGHT-IN LANDING− A landing made on a (See ALTITUDE READOUT.) runway aligned within 30 of the final approach (See TRANSPONDER.) course following completion of an instrument approach. STOP AND GO− A procedure wherein an aircraft (See STRAIGHT-IN APPROACH IFR.) will land, make a complete stop on the runway, and then commence a takeoff from that point. STRAIGHT-IN LANDING MINIMUMS− (See LOW APPROACH.) (See LANDING MINIMUMS.) (See OPTION APPROACH.) STRAIGHT-IN MINIMUMS− STOP BURST− (See STRAIGHT-IN LANDING MINIMUMS.) (See STOP STREAM.) STRATEGIC PLANNING− Planning whereby STOP BUZZER− solutions are sought to resolve potential conflicts. (See STOP STREAM.) sUAS− STOP SQUAWK (Mode or Code)− Used by ATC to (See SMALL UNMANNED AIRCRAFT instruct a pilot to stop transponder and ADS−B SYSTEM.)

PCG S−8 6/17/21 Pilot/Controller Glossary

SUBSTITUTE ROUTE− A route assigned to pilots SURFACE AREA− The airspace contained by the when any part of an airway or route is unusable lateral boundary of the Class B, C, D, or E airspace because of NAVAID status. These routes consist of: designated for an airport that begins at the surface and extends upward. a. Substitute routes which are shown on U.S. Government charts. SURPIC− A description of surface vessels in the area of a Search and Rescue incident including their b. Routes defined by ATC as specific NAVAID predicted positions and their characteristics. radials or courses. (Refer to FAA Order JO 7110.65, Para 10−6−4, c. Routes defined by ATC as direct to or between INFLIGHT CONTINGENCIES.) NAVAIDs. SURVEILLANCE APPROACH− An instrument approach wherein the air traffic controller issues SUNSET AND SUNRISE− The mean solar times of instructions, for pilot compliance, based on aircraft sunset and sunrise as published in the Nautical position in relation to the final approach course Almanac, converted to local standard time for the (azimuth), and the distance (range) from the end of locality concerned. Within Alaska, the end of evening the runway as displayed on the controller’s radar civil twilight and the beginning of morning civil scope. The controller will provide recommended twilight, as defined for each locality. altitudes on final approach if requested by the pilot. SUPPLEMENTAL WEATHER SERVICE LOCA- (Refer to AIM.) TION− Airport facilities staffed with contract SWAP− personnel who take weather observations and (See SEVERE WEATHER AVOIDANCE PLAN.) provide current local weather to pilots via telephone SWSL− or radio. (All other services are provided by the parent FSS.) (See SUPPLEMENTAL WEATHER SERVICE LOCATION.) SUPPS− Refers to ICAO Document 7030 Regional SYSTEM STRATEGIC NAVIGATION− Military Supplementary Procedures. SUPPS contain activity accomplished by navigating along a procedures for each ICAO Region which are unique preplanned route using internal aircraft systems to to that Region and are not covered in the worldwide maintain a desired track. This activity normally provisions identified in the ICAO Air Navigation requires a lateral route width of 10 NM and altitude Plan. Procedures contained in Chapter 8 are based in range of 1,000 feet to 6,000 feet AGL with some route part on those published in SUPPS. segments that permit terrain following.

PCG S−9

6/17/21 Pilot/Controller Glossary T

TACAN− this pertains to the act of becoming airborne after (See TACTICAL AIR NAVIGATION.) departing a takeoff area. TACAN-ONLY AIRCRAFT− An aircraft, normally TAKEOFF RUN AVAILABLE (TORA) – The military, possessing TACAN with DME but no VOR runway length declared available and suitable for the navigational system capability. Clearances must ground run of an airplane taking off. specify TACAN or VORTAC fixes and approaches. (See ICAO term TAKEOFF RUN AVAILABLE.) TAKEOFF RUN AVAILABLE [ICAO]− The length TACTICAL AIR NAVIGATION (TCAN)− An of runway declared available and suitable for the ultra-high frequency electronic rho-theta air naviga- ground run of an aeroplane take-off. tion aid which provides suitably equipped aircraft a continuous indication of bearing and distance to the TARGET− The indication shown on a display TACAN station. resulting from a primary radar return, a radar beacon (See VORTAC.) reply, or an ADS−B report. The specific target (Refer to AIM.) symbol presented to ATC may vary based on the surveillance source and automation platform. TAILWIND− Any wind more than 90 degrees to the (See ASSOCIATED.) longitudinal axis of the runway. The magnetic (See DIGITAL TARGET.) direction of the runway shall be used as the basis for (See DIGITIZED RADAR TARGET.) determining the longitudinal axis. (See FUSED TARGET.) (See PRIMARY RADAR TARGET.) TAKEOFF AREA− (See RADAR.) (See LANDING AREA.) (See SECONDARY RADAR TARGET.) TAKEOFF DISTANCE AVAILABLE (TODA)– The (See ICAO term TARGET.) takeoff run available plus the length of any remaining (See UNASSOCIATED.) runway or clearway beyond the far end of the takeoff TARGET [ICAO]− In radar: run available. a. Generally, any discrete object which reflects or (See ICAO term TAKEOFF DISTANCE retransmits energy back to the radar equipment. AVAILABLE.) b. Specifically, an object of radar search or TAKEOFF DISTANCE AVAILABLE [ICAO]− The surveillance. length of the takeoff run available plus the length of TARGET RESOLUTION− A process to ensure that the clearway, if provided. correlated radar targets do not touch. Target TAKEOFF HOLD LIGHTS (THL)– The THL resolution must be applied as follows: system is composed of in-pavement lighting in a a. Between the edges of two primary targets or the double, longitudinal row of lights aligned either side edges of the ASR-9/11 primary target symbol. of the runway centerline. The lights are focused b. Between the end of the beacon control slash and toward the arrival end of the runway at the “line up the edge of a primary target. and wait” point, and they extend for 1,500 feet in c. Between the ends of two beacon control slashes. front of the holding aircraft. Illuminated red lights Note 1: Mandatory traffic advisories and safety indicate to an aircraft in position for takeoff or rolling alerts must be issued when this procedure is used. that it is unsafe to takeoff because the runway is Note 2: This procedure must not be used when occupied or about to be occupied by an aircraft or utilizing mosaic radar systems or multi−sensor vehicle. mode. TAKEOFF ROLL − The process whereby an aircraft TARGET SYMBOL− is aligned with the runway centerline and the aircraft (See TARGET.) is moving with the intent to take off. For helicopters, (See ICAO term TARGET.)

PCG T−1 Pilot/Controller Glossary 6/17/21

TARMAC DELAY− The holding of an aircraft on the territories to restrict certain aircraft from operating ground either before departure or after landing with within a defined area on a temporary basis to protect no opportunity for its passengers to deplane. persons or property in the air or on the ground. While not all inclusive, TFRs may be issued for disaster or TARMAC DELAY AIRCRAFT− An aircraft whose hazard situations such as: toxic gas leaks or spills, pilot−in−command has requested to taxi to the ramp, fumes from flammable agents, aircraft accident/in- gate, or alternate deplaning area to comply with the cident sites, aviation or ground resources engaged in Three−hour Tarmac Rule. wildfire suppression, or aircraft relief activities TARMAC DELAY REQUEST− A request by the following a disaster. TFRs may also be issued in pilot−in−command to taxi to the ramp, gate, or support of VIP movements, for reasons of national alternate deplaning location to comply with the security; or when determined necessary for the Three−hour Tarmac Rule. management of air traffic in the vicinity of aerial demonstrations or major sporting events. NAS users TAS− or other interested parties should contact a FSS for (See TERMINAL AUTOMATION SYSTEMS.) TFR information. Additionally, TFR information can TAWS− be found in automated briefings, NOTAM publica- (See TERRAIN AWARENESS WARNING tions, and on the internet at http://www.faa.gov. The SYSTEM.) FAA also distributes TFR information to aviation user groups for further dissemination. TAXI− The movement of an airplane under its own power on the surface of an airport (14 CFR TENTATIVE CALCULATED LANDING TIME Section 135.100 [Note]). Also, it describes the (TCLT)− A projected time calculated for adapted surface movement of helicopters equipped with vertex for each arrival aircraft based upon runway wheels. configuration, airport acceptance rate, airport arrival (See AIR TAXI.) delay period, and other metered arrival aircraft. This (See HOVER TAXI.) time is either the VTA of the aircraft or the (Refer to 14 CFR Section 135.100.) TCLT/ACLT of the previous aircraft plus the AAI, (Refer to AIM.) whichever is later. This time will be updated in response to an aircraft’s progress and its current TAXI PATTERNS− Patterns established to illustrate relationship to other arrivals. the desired flow of ground traffic for the different runways or airport areas available for use. TERMINAL AREA− A general term used to describe airspace in which approach control service or airport TCAS− traffic control service is provided. (See TRAFFIC ALERT AND COLLISION AVOIDANCE SYSTEM.) TERMINAL AREA FACILITY− A facility providing air traffic control service for arriving and TCH− departing IFR, VFR, Special VFR, and on occasion (See THRESHOLD CROSSING HEIGHT.) en route aircraft. TCLT− (See APPROACH CONTROL FACILITY.) (See TENTATIVE CALCULATED LANDING (See TOWER.) TIME.) TERMINAL AUTOMATION SYSTEMS (TAS)− TDLS− TAS is used to identify the numerous automated tracking systems including STARS and MEARTS. (See TERMINAL DATA LINK SYSTEM.) TERMINAL DATA LINK SYSTEM (TDLS)− A TDZE− system that provides Digital Automatic Terminal (See TOUCHDOWN ZONE ELEVATION.) Information Service (D−ATIS) both on a specified TEMPORARY FLIGHT RESTRICTION (TFR)− A radio frequency and also, for subscribers, in a text TFR is a regulatory action issued by the FAA via the message via data link to the cockpit or to a gate U.S. NOTAM System, under the authority of United printer. TDLS also provides Pre−departure Clear- States Code, Title 49. TFRs are issued within the ances (PDC), at selected airports, to subscribers, sovereign airspace of the United States and its through a service provider, in text to the cockpit or to

PCG T−2 6/17/21 Pilot/Controller Glossary

a gate printer. In addition, TDLS will emulate the of aircraft based on IFR, VFR, and/or weight, and Flight Data Input/Output (FDIO) information within sequencing of VFR arrivals to the primary airport(s). the control tower. (See CONTROLLED AIRSPACE.) (See TERMINAL RADAR SERVICE AREA.) TERMINAL RADAR SERVICE AREA− Airspace (Refer to AIM.) surrounding designated airports wherein ATC (Refer to CHART SUPPLEMENT U.S.) provides radar vectoring, sequencing, and separation TERMINAL-VERY HIGH FREQUENCY OMNI- on a full-time basis for all IFR and participating VFR DIRECTIONAL RANGE STATION (TVOR)− A aircraft. The AIM contains an explanation of TRSA. very high frequency terminal omnirange station TRSAs are depicted on VFR aeronautical charts. located on or near an airport and used as an approach Pilot participation is urged but is not mandatory. aid. (See NAVIGATIONAL AID.) TERMINAL VFR RADAR SERVICE− A national (See VOR.) program instituted to extend the terminal radar TERRAIN AWARENESS WARNING SYSTEM services provided instrument flight rules (IFR) (TAWS)− An on−board, terrain proximity alerting aircraft to visual flight rules (VFR) aircraft. The system providing the aircrew ‘Low Altitude program is divided into four types service referred to warnings’ to allow immediate pilot action. as basic radar service, terminal radar service area (TRSA) service, Class B service and Class C service. TERRAIN FOLLOWING− The flight of a military The type of service provided at a particular location aircraft maintaining a constant AGL altitude above is contained in the Chart Supplement U.S. the terrain or the highest obstruction. The altitude of the aircraft will constantly change with the varying a. Basic Radar Service− These services are terrain and/or obstruction. provided for VFR aircraft by all commissioned TETRAHEDRON− A device normally located on terminal radar facilities. Basic radar service includes uncontrolled airports and used as a landing direction safety alerts, traffic advisories, limited radar indicator. The small end of a tetrahedron points in the vectoring when requested by the pilot, and direction of landing. At controlled airports, the sequencing at locations where procedures have been tetrahedron, if installed, should be disregarded established for this purpose and/or when covered by because tower instructions supersede the indicator. a letter of agreement. The purpose of this service is to (See SEGMENTED CIRCLE.) adjust the flow of arriving IFR and VFR aircraft into (Refer to AIM.) the traffic pattern in a safe and orderly manner and to provide traffic advisories to departing VFR aircraft. TF− (See TERRAIN FOLLOWING.) b. TRSA Service− This service provides, in addition to basic radar service, sequencing of all IFR THAT IS CORRECT− The understanding you have and participating VFR aircraft to the primary airport is right. and separation between all participating VFR THA− aircraft. The purpose of this service is to provide (See TRANSITIONAL HAZARD AREA.) separation between all participating VFR aircraft and THREE−HOUR TARMAC RULE– Rule that relates all IFR aircraft operating within the area defined as a to Department of Transportation (DOT) requirements TRSA. placed on airlines when tarmac delays are anticipated c. Class C Service− This service provides, in to reach 3 hours. addition to basic radar service, approved separation 360 OVERHEAD− between IFR and VFR aircraft, and sequencing of (See OVERHEAD MANEUVER.) VFR aircraft, and sequencing of VFR arrivals to the primary airport. THRESHOLD− The beginning of that portion of the runway usable for landing. d. Class B Service− This service provides, in (See AIRPORT LIGHTING.) addition to basic radar service, approved separation (See DISPLACED THRESHOLD.)

PCG T−3 Pilot/Controller Glossary 6/17/21

THRESHOLD CROSSING HEIGHT− The TIS−B− theoretical height above the runway threshold at (See TRAFFIC INFORMATION which the aircraft’s glideslope antenna would be if SERVICE−BROADCAST.) the aircraft maintains the trajectory established by the TMPA− mean ILS glideslope or the altitude at which the (See TRAFFIC MANAGEMENT PROGRAM calculated glidepath of an RNAV or GPS approaches. ALERT.) (See GLIDESLOPE.) TMU− (See THRESHOLD.) (See TRAFFIC MANAGEMENT UNIT.) THRESHOLD LIGHTS− TODA− (See TAKEOFF DISTANCE AVAILABLE.) (See AIRPORT LIGHTING.) (See ICAO term TAKEOFF DISTANCE AVAILABLE.) TIE-IN FACILITY– The FSS primarily responsible for providing FSS services, including telecommu- TOI− nications services for landing facilities or (See TRACK OF INTEREST.) navigational aids located within the boundaries of a TOP ALTITUDE− In reference to SID published flight plan area (FPA). Three-letter identifiers are altitude restrictions, the charted “maintain” altitude assigned to each FSS/FPA and are annotated as tie-in contained in the procedure description or assigned by facilities in the Chart Supplement U.S., the Alaska ATC. Supplement, the Pacific Supplement, and FAA Order JO 7350.9, Location Identifiers. Large consolidated TORA− FSS facilities may have many tie-in facilities or FSS (See TAKEOFF RUN AVAILABLE.) sectors within one facility. (See ICAO term TAKEOFF RUN AVAILABLE.) (See FLIGHT PLAN AREA.) TORCHING− The burning of fuel at the end of an (See FLIGHT SERVICE STATION.) exhaust pipe or stack of a reciprocating aircraft engine, the result of an excessive richness in the fuel TIME−BASED FLOW MANAGEMENT (TBFM)− air mixture. The hardware, software, methods, processes, and TOS− initiatives to manage air traffic flows based on time (See TRAJECTORY OPTIONS SET) to balance air traffic demand with system capacity, TOTAL ESTIMATED ELAPSED TIME [ICAO]− and support the management of PBN. This includes, For IFR flights, the estimated time required from but not limited to, Adjacent Center Metering (ACM), takeoff to arrive over that designated point, defined En Route Departure Capability (EDC), by reference to navigation aids, from which it is Ground−based Interval Management-Spacing intended that an instrument approach procedure will (GIM-S), Integrated Departure/Arrival Capability be commenced, or, if no navigation aid is associated (IDAC), Single Center Metering (SCM), with the destination aerodrome, to arrive over the Time−Based Metering (TBM), Time−Based destination aerodrome. For VFR flights, the Scheduling (TBS), and Extended/Coupled Metering. estimated time required from takeoff to arrive over the destination aerodrome. TIME GROUP− Four digits representing the hour and minutes from the Coordinated Universal Time (See ICAO term ESTIMATED ELAPSED TIME.) (UTC) clock. FAA uses UTC for all operations. The TOUCH-AND-GO− An operation by an aircraft that term “ZULU” may be used to denote UTC. The word lands and departs on a runway without stopping or “local” or the time zone equivalent shall be used to exiting the runway. denote local when local time is given during radio and TOUCH-AND-GO LANDING− telephone communications. When written, a time (See TOUCH-AND-GO.) zone designator is used to indicate local time; e.g., “0205M” (Mountain). The local time may be based TOUCHDOWN− on the 24-hour clock system. The day begins at 0000 a. The point at which an aircraft first makes and ends at 2359. contact with the landing surface.

PCG T−4 6/17/21 Pilot/Controller Glossary

b. Concerning a precision radar approach (PAR), TOWER EN ROUTE CONTROL SERVICE− The it is the point where the glide path intercepts the control of IFR en route traffic within delegated landing surface. airspace between two or more adjacent approach (See ICAO term TOUCHDOWN.) control facilities. This service is designed to expedite traffic and reduce control and pilot communication TOUCHDOWN [ICAO]− The point where the requirements. nominal glide path intercepts the runway. TOWER TO TOWER− Note: Touchdown as defined above is only a datum and is not necessarily the actual point at which the (See TOWER EN ROUTE CONTROL aircraft will touch the runway. SERVICE.) TRACEABLE PRESSURE STANDARD− The TOUCHDOWN RVR− facility station pressure instrument, with certifica- (See VISIBILITY.) tion/calibration traceable to the National Institute of Standards and Technology. Traceable pressure TOUCHDOWN ZONE− The first 3,000 feet of the standards may be mercurial barometers, commis- runway beginning at the threshold. The area is used sioned ASOS or dual transducer AWOS, or portable for determination of Touchdown Zone Elevation in pressure standards or DASI. the development of straight-in landing minimums for instrument approaches. TRACK− The actual flight path of an aircraft over the (See ICAO term TOUCHDOWN ZONE.) surface of the earth. (See COURSE.) TOUCHDOWN ZONE [ICAO]− The portion of a (See FLIGHT PATH.) runway, beyond the threshold, where it is intended (See ROUTE.) landing aircraft first contact the runway. (See ICAO term TRACK.) TOUCHDOWN ZONE ELEVATION− The highest TRACK [ICAO]− The projection on the earth’s elevation in the first 3,000 feet of the landing surface. surface of the path of an aircraft, the direction of TDZE is indicated on the instrument approach which path at any point is usually expressed in procedure chart when straight-in landing minimums degrees from North (True, Magnetic, or Grid). are authorized. TRACK OF INTEREST (TOI)− Displayed data (See TOUCHDOWN ZONE.) representing an airborne object that threatens or has TOUCHDOWN ZONE LIGHTING− the potential to threaten North America or National Security. Indicators may include, but are not limited (See AIRPORT LIGHTING.) to: noncompliance with air traffic control instructions TOWER− A terminal facility that uses air/ground or aviation regulations; extended loss of communica- communications, visual signaling, and other devices tions; unusual transmissions or unusual flight to provide ATC services to aircraft operating in the behavior; unauthorized intrusion into controlled vicinity of an airport or on the movement area. airspace or an ADIZ; noncompliance with issued Authorizes aircraft to land or takeoff at the airport flight restrictions/security procedures; or unlawful controlled by the tower or to transit the Class D interference with airborne flight crews, up to and airspace area regardless of flight plan or weather including hijack. In certain circumstances, an object conditions (IFR or VFR). A tower may also provide may become a TOI based on specific and credible approach control services (radar or nonradar). intelligence pertaining to that particular aircraft/ (See AIRPORT TRAFFIC CONTROL SERVICE.) object, its passengers, or its cargo. (See APPROACH CONTROL FACILITY.) TRACK OF INTEREST RESOLUTION− A TOI (See APPROACH CONTROL SERVICE.) will normally be considered resolved when: the (See MOVEMENT AREA.) aircraft/object is no longer airborne; the aircraft (See TOWER EN ROUTE CONTROL complies with air traffic control instructions, aviation SERVICE.) regulations, and/or issued flight restrictions/security (See ICAO term AERODROME CONTROL procedures; radio contact is re−established and TOWER.) authorized control of the aircraft is verified; the (Refer to AIM.) aircraft is intercepted and intent is verified to be

PCG T−5 Pilot/Controller Glossary 6/17/21 nonthreatening/nonhostile; TOI was identified based avoidance system based on radar beacon signals on specific and credible intelligence that was later which operates independent of ground-based equip- determined to be invalid or unreliable; or displayed ment. TCAS-I generates traffic advisories only. data is identified and characterized as invalid. TCAS-II generates traffic advisories, and resolution (collision avoidance) advisories in the vertical plane. TRAFFIC−

a. A term used by a controller to transfer radar TRAFFIC INFORMATION− identification of an aircraft to another controller for (See TRAFFIC ADVISORIES.) the purpose of coordinating separation action. Traffic TRAFFIC INFORMATION SERVICE−BROAD- is normally issued: CAST (TIS−B)− The broadcast of ATC derived 1. In response to a handoff or point out, traffic information to ADS−B equipped (1090ES or UAT) aircraft. The source of this traffic information 2. In anticipation of a handoff or point out, or is derived from ground−based air traffic surveillance 3. In conjunction with a request for control of an sensors, typically from radar targets. TIS−B service aircraft. will be available throughout the NAS where there are b. A term used by ATC to refer to one or more both adequate surveillance coverage (radar) and aircraft. adequate broadcast coverage from ADS−B ground stations. Loss of TIS−B will occur when an aircraft TRAFFIC ADVISORIES− Advisories issued to alert enters an area not covered by the GBT network. If this pilots to other known or observed air traffic which occurs in an area with adequate surveillance coverage may be in such proximity to the position or intended (radar), nearby aircraft that remain within the route of flight of their aircraft to warrant their adequate broadcast coverage (ADS−B) area will view attention. Such advisories may be based on: the first aircraft. TIS−B may continue when an a. Visual observation. aircraft enters an area with inadequate surveillance b. Observation of radar identified and nonidenti- coverage (radar); nearby aircraft that remain within fied aircraft targets on an ATC radar display, or the adequate broadcast coverage (ADS−B) area will c. Verbal reports from pilots or other facilities. not view the first aircraft. Note 1: The word “traffic” followed by additional TRAFFIC IN SIGHT− Used by pilots to inform a information, if known, is used to provide such controller that previously issued traffic is in sight. advisories; e.g., “Traffic, 2 o’clock, one zero miles, (See NEGATIVE CONTACT.) southbound, eight thousand.” (See TRAFFIC ADVISORIES.) Note 2: Traffic advisory service will be provided to TRAFFIC MANAGEMENT PROGRAM ALERT− the extent possible depending on higher priority A term used in a Notice to Airmen (NOTAM) issued duties of the controller or other limitations; e.g., in conjunction with a special traffic management radar limitations, volume of traffic, frequency program to alert pilots to the existence of the program congestion, or controller workload. Radar/ nonradar traffic advisories do not relieve the pilot and to refer them to a special traffic management of his/her responsibility to see and avoid other program advisory message for program details. The aircraft. Pilots are cautioned that there are many contraction TMPA is used in NOTAM text. times when the controller is not able to give traffic TRAFFIC MANAGEMENT UNIT− The entity in advisories concerning all traffic in the aircraft’s ARTCCs and designated terminals directly involved proximity; in other words, when a pilot requests or in the active management of facility traffic. Usually is receiving traffic advisories, he/she should not under the direct supervision of an assistant manager assume that all traffic will be issued. for traffic management. (Refer to AIM.) TRAFFIC NO FACTOR− Indicates that the traffic TRAFFIC ALERT (aircraft call sign), TURN described in a previously issued traffic advisory is no (left/right) IMMEDIATELY, (climb/descend) AND factor. MAINTAIN (altitude). TRAFFIC NO LONGER OBSERVED− Indicates (See SAFETY ALERT.) that the traffic described in a previously issued traffic TRAFFIC ALERT AND COLLISION AVOID- advisory is no longer depicted on radar, but may still ANCE SYSTEM (TCAS)− An airborne collision be a factor.

PCG T−6 6/17/21 Pilot/Controller Glossary

TRAFFIC PATTERN− The traffic flow that is TRAJECTORY MODELING− The automated pro- prescribed for aircraft landing at, taxiing on, or taking cess of calculating a trajectory. off from an airport. The components of a typical traffic pattern are upwind leg, crosswind leg, TRAJECTORY OPTIONS SET (TOS)− A TOS is an downwind leg, base leg, and final approach. electronic message, submitted by the operator, that is used by the Collaborative Trajectory Options a. Upwind Leg− A flight path parallel to the Program (CTOP) to manage the airspace captured in landing runway in the direction of landing. the traffic management program. The TOS will allow b. Crosswind Leg− A flight path at right angles to the operator to express the route and delay trade-off the landing runway off its upwind end. options that they are willing to accept. c. Downwind Leg− A flight path parallel to the TRANSFER OF CONTROL− That action whereby landing runway in the direction opposite to landing. the responsibility for the separation of an aircraft is The downwind leg normally extends between the transferred from one controller to another. crosswind leg and the base leg. (See ICAO term TRANSFER OF CONTROL.) d. Base Leg− A flight path at right angles to the TRANSFER OF CONTROL [ICAO]− Transfer of landing runway off its approach end. The base leg responsibility for providing air traffic control service. normally extends from the downwind leg to the intersection of the extended runway centerline. TRANSFERRING CONTROLLER− A controller/ e. Final Approach− A flight path in the direction facility transferring control of an aircraft to another of landing along the extended runway centerline. The controller/facility. final approach normally extends from the base leg to (See ICAO term TRANSFERRING the runway. An aircraft making a straight-in approach UNIT/CONTROLLER.) VFR is also considered to be on final approach. TRANSFERRING FACILITY− (See STRAIGHT-IN APPROACH VFR.) (See TRANSFERRING CONTROLLER.) (See TAXI PATTERNS.) TRANSFERRING UNIT/CONTROLLER [ICAO]− (See ICAO term AERODROME TRAFFIC CIRCUIT.) Air traffic control unit/air traffic controller in the process of transferring the responsibility for (Refer to 14 CFR Part 91.) providing air traffic control service to an aircraft to (Refer to AIM.) the next air traffic control unit/air traffic controller TRAFFIC SITUATION DISPLAY (TSD)− TSD is a along the route of flight. computer system that receives radar track data from Note: See definition of accepting unit/controller. all 20 CONUS ARTCCs, organizes this data into a mosaic display, and presents it on a computer screen. TRANSITION− The display allows the traffic management coordina- a. The general term that describes the change from tor multiple methods of selection and highlighting of one phase of flight or flight condition to another; e.g., individual aircraft or groups of aircraft. The user has transition from en route flight to the approach or the option of superimposing these aircraft positions transition from instrument flight to visual flight. over any number of background displays. These b. A published procedure (DP Transition) used to background options include ARTCC boundaries, any connect the basic DP to one of several en route stratum of en route sector boundaries, fixes, airways, airways/jet routes, or a published procedure (STAR military and other special use airspace, airports, and Transition) used to connect one of several en route geopolitical boundaries. By using the TSD, a airways/jet routes to the basic STAR. coordinator can monitor any number of traffic (Refer to DP/STAR Charts.) situations or the entire systemwide traffic flows. TRANSITION POINT− A point at an adapted TRAJECTORY− A EDST representation of the path number of miles from the vertex at which an arrival an aircraft is predicted to fly based upon a Current aircraft would normally commence descent from its Plan or Trial Plan. en route altitude. This is the first fix adapted on the (See EN ROUTE DECISION SUPPORT TOOL.) arrival speed segments.

PCG T−7 Pilot/Controller Glossary 6/17/21

TRANSITION WAYPOINT− The waypoint that reply has been observed and its position correlated for defines the beginning of a runway or en route transit through the designated area. transition on an RNAV SID or STAR. TRIAL PLAN− A proposed amendment which TRANSITIONAL AIRSPACE− That portion of utilizes automation to analyze and display potential controlled airspace wherein aircraft change from one conflicts along the predicted trajectory of the selected phase of flight or flight condition to another. aircraft. TRANSITIONAL HAZARD AREA (THA)− Used TRSA− by ATC. Airspace normally associated with an (See TERMINAL RADAR SERVICE AREA.) Aircraft Hazard Area within which the flight of aircraft is subject to restrictions. TSD− (See AIRCRAFT HAZARD AREA.) (See TRAFFIC SITUATION DISPLAY.) (See CONTINGENCY HAZARD AREA.) TURBOJET AIRCRAFT− An aircraft having a jet (See REFINED HAZARD AREA.) engine in which the energy of the jet operates a TRANSMISSOMETER− An apparatus used to turbine which in turn operates the air compressor. determine visibility by measuring the transmission of TURBOPROP AIRCRAFT− An aircraft having a jet light through the atmosphere. It is the measurement engine in which the energy of the jet operates a source for determining runway visual range (RVR). turbine which drives the propeller. (See VISIBILITY.) TURBULENCE− An atmospheric phenomenon that TRANSMITTING IN THE BLIND− A transmis- causes changes in aircraft altitude, attitude, and or sion from one station to other stations in airspeed with aircraft reaction depending on circumstances where two-way communication intensity. Pilots report turbulence intensity according cannot be established, but where it is believed that the to aircraft’s reaction as follows: called stations may be able to receive the transmission. a. Light − Causes slight, erratic changes in altitude and or attitude (pitch, roll, or yaw). TRANSPONDER− The airborne radar beacon b. Moderate− Similar to Light but of greater receiver/transmitter portion of the Air Traffic Control intensity. Changes in altitude and or attitude occur Radar Beacon System (ATCRBS) which automati- but the aircraft remains in positive control at all times. cally receives radio signals from interrogators on the It usually causes variations in indicated airspeed. ground, and selectively replies with a specific reply pulse or pulse group only to those interrogations c. Severe− Causes large, abrupt changes in altitude being received on the mode to which it is set to and or attitude. It usually causes large variations in respond. indicated airspeed. Aircraft may be momentarily out of control. (See INTERROGATOR.) (See ICAO term TRANSPONDER.) d. Extreme− The aircraft is violently tossed about (Refer to AIM.) and is practically impossible to control. It may cause structural damage. TRANSPONDER [ICAO]− A receiver/transmitter (See CHOP.) which will generate a reply signal upon proper (Refer to AIM.) interrogation; the interrogation and reply being on different frequencies. TURN ANTICIPATION− (maneuver anticipation). TRANSPONDER CODES− TVOR− (See CODES.) (See TERMINAL-VERY HIGH FREQUENCY OMNIDIRECTIONAL RANGE STATION.) TRANSPONDER OBSERVED − Phraseology used to inform a VFR pilot the aircraft’s assigned beacon TWO-WAY RADIO COMMUNICATIONS FAIL- code and position have been observed. Specifically, URE− this term conveys to a VFR pilot the transponder (See LOST COMMUNICATIONS.)

PCG T−8 6/17/21 Pilot/Controller Glossary U

UHF− UNMANNED AIRCRAFT (UA)- A device used or (See ULTRAHIGH FREQUENCY.) intended to be used for flight that has no onboard pilot. This device can be any type of airplane, ULTRAHIGH FREQUENCY (UHF)− The frequen- helicopter, airship, or powered-lift aircraft. cy band between 300 and 3,000 MHz. The bank of Unmanned free balloons, moored balloons, tethered radio frequencies used for military air/ground voice aircraft, gliders, and unmanned rockets are not communications. In some instances this may go as considered to be a UA. low as 225 MHz and still be referred to as UHF. UNMANNED AIRCRAFT SYSTEM (UAS)- An ULTRALIGHT VEHICLE− A single-occupant unmanned aircraft and its associated elements related aeronautical vehicle operated for sport or recreational to safe operations, which may include control purposes which does not require FAA registration, an stations (ground, ship, or air based), control links, airworthiness certificate, or pilot certification. support equipment, payloads, flight termination Operation of an ultralight vehicle in certain airspace systems, and launch/recovery equipment. It consists requires authorization from ATC. of three elements: unmanned aircraft, control station, (Refer to 14 CFR Part 103.) and data link.

UNABLE− Indicates inability to comply with a UNPUBLISHED ROUTE− A route for which no specific instruction, request, or clearance. minimum altitude is published or charted for pilot UNASSOCIATED− A radar target that does not use. It may include a direct route between NAVAIDs, display a data block with flight identification and a radial, a radar vector, or a final approach course altitude information. beyond the segments of an instrument approach (See ASSOCIATED.) procedure. (See PUBLISHED ROUTE.) UNCONTROLLED AIRSPACE− Airspace in which (See ROUTE.) aircraft are not subject to controlled airspace (Class A, B, C, D, or E) separation criteria. UNRELIABLE (GPS/WAAS)− An advisory to pilots indicating the expected level of service of the UNDER THE HOOD− Indicates that the pilot is GPS and/or WAAS may not be available. Pilots must using a hood to restrict visibility outside the cockpit then determine the adequacy of the signal for desired while simulating instrument flight. An appropriately use. rated pilot is required in the other control seat while this operation is being conducted. UNSERVICEABLE (U/S) (Refer to 14 CFR Part 91.) (See OUT OF SERVICE/UNSERVICEABLE.) UNFROZEN− The Scheduled Time of Arrival (STA) UPWIND LEG− tags, which are still being rescheduled by the (See TRAFFIC PATTERN.) time−based flow management (TBFM) calculations. URGENCY− A condition of being concerned about The aircraft will remain unfrozen until the time the safety and of requiring timely but not immediate corresponding estimated time of arrival (ETA) tag assistance; a potential distress condition. passes the preset freeze horizon for that aircraft’s stream class. At this point the automatic rescheduling (See ICAO term URGENCY.) will stop, and the STA becomes “frozen.” URGENCY [ICAO]− A condition concerning the UNICOM− A nongovernment communication facil- safety of an aircraft or other vehicle, or of person on ity which may provide airport information at certain board or in sight, but which does not require airports. Locations and frequencies of UNICOMs are immediate assistance. shown on aeronautical charts and publications. USAFIB− (See CHART SUPPLEMENT U.S.) (See ARMY AVIATION FLIGHT INFORMATION (Refer to AIM.) BULLETIN.)

PCG U−1

6/17/21 Pilot/Controller Glossary V

VASI− and/or descents and of using very short runways or (See VISUAL APPROACH SLOPE INDICATOR.) small areas for takeoff and landings. These aircraft include, but are not limited to, helicopters.

VCOA− (See SHORT TAKEOFF AND LANDING (See VISUAL CLIMB OVER AIRPORT.) AIRCRAFT.) VDP− VERY HIGH FREQUENCY (VHF)− The frequency (See VISUAL DESCENT POINT.) band between 30 and 300 MHz. Portions of this band, 108 to 118 MHz, are used for certain NAVAIDs; 118 VECTOR− A heading issued to an aircraft to provide to 136 MHz are used for civil air/ground voice navigational guidance by radar. communications. Other frequencies in this band are (See ICAO term RADAR VECTORING.) used for purposes not related to air traffic control. VERIFY− Request confirmation of information; VERY HIGH FREQUENCY OMNIDIRECTION- e.g., “verify assigned altitude.” AL RANGE STATION− VERIFY SPECIFIC DIRECTION OF TAKEOFF (See VOR.) (OR TURNS AFTER TAKEOFF)− Used by ATC to VERY LOW FREQUENCY (VLF)− The frequency ascertain an aircraft’s direction of takeoff and/or band between 3 and 30 kHz. direction of turn after takeoff. It is normally used for VFR− IFR departures from an airport not having a control (See VISUAL FLIGHT RULES.) tower. When direct communication with the pilot is not possible, the request and information may be VFR AIRCRAFT− An aircraft conducting flight in relayed through an FSS, dispatcher, or by other accordance with visual flight rules. means. (See VISUAL FLIGHT RULES.) (See IFR TAKEOFF MINIMUMS AND VFR CONDITIONS− Weather conditions equal to DEPARTURE PROCEDURES.) or better than the minimum for flight under visual VERTEX− The last fix adapted on the arrival speed flight rules. The term may be used as an ATC segments. Normally, it will be the outer marker of the clearance/instruction only when: runway in use. However, it may be the actual a. An IFR aircraft requests a climb/descent in threshold or other suitable common point on the VFR conditions. approach path for the particular runway configura- b. The clearance will result in noise abatement tion. benefits where part of the IFR departure route does VERTEX TIME OF ARRIVAL− A calculated time of not conform to an FAA approved noise abatement aircraft arrival over the adapted vertex for the runway route or altitude. configuration in use. The time is calculated via the c. A pilot has requested a practice instrument optimum flight path using adapted speed segments. approach and is not on an IFR flight plan. Note: All pilots receiving this authorization must VERTICAL NAVIGATION (VNAV)– A function of comply with the VFR visibility and distance from area navigation (RNAV) equipment which calculates, cloud criteria in 14 CFR Part 91. Use of the term displays, and provides vertical guidance to a profile does not relieve controllers of their responsibility to or path. separate aircraft in Class B and Class C airspace or TRSAs as required by FAA Order JO 7110.65. VERTICAL SEPARATION− Separation between When used as an ATC clearance/instruction, the aircraft expressed in units of vertical distance. term may be abbreviated “VFR;” e.g., “MAINTAIN (See SEPARATION.) VFR,” “CLIMB/DESCEND VFR,” etc. VERTICAL TAKEOFF AND LANDING AIR- VFR FLIGHT− CRAFT (VTOL)− Aircraft capable of vertical climbs (See VFR AIRCRAFT.)

PCG V−1 Pilot/Controller Glossary 6/17/21

VFR MILITARY TRAINING ROUTES (VR)− night. Visibility is reported as statute miles, hundreds Routes used by the Department of Defense and of feet or meters. associated Reserve and Air Guard units for the (Refer to 14 CFR Part 91.) purpose of conducting low-altitude navigation and (Refer to AIM.) tactical training under VFR below 10,000 feet MSL a. Flight Visibility− The average forward horizon- at airspeeds in excess of 250 knots IAS. tal distance, from the cockpit of an aircraft in flight, at which prominent unlighted objects may be seen VFR NOT RECOMMENDED− An advisory and identified by day and prominent lighted objects provided by a flight service station to a pilot during may be seen and identified by night. a preflight or inflight weather briefing that flight under visual flight rules is not recommended. To be b. Ground Visibility− Prevailing horizontal visi- given when the current and/or forecast weather bility near the earth’s surface as reported by the conditions are at or below VFR minimums. It does United States National Weather Service or an not abrogate the pilot’s authority to make his/her own accredited observer. decision. c. Prevailing Visibility− The greatest horizontal visibility equaled or exceeded throughout at least half VFR-ON-TOP− ATC authorization for an IFR the horizon circle which need not necessarily be aircraft to operate in VFR conditions at any continuous. appropriate VFR altitude (as specified in 14 CFR and d. Runway Visual Range (RVR)− An instrumen- as restricted by ATC). A pilot receiving this tally derived value, based on standard calibrations, authorization must comply with the VFR visibility, that represents the horizontal distance a pilot will see distance from cloud criteria, and the minimum IFR down the runway from the approach end. It is based altitudes specified in 14 CFR Part 91. The use of this on the sighting of either high intensity runway lights term does not relieve controllers of their responsibil- or on the visual contrast of other targets whichever ity to separate aircraft in Class B and Class C airspace yields the greater visual range. RVR, in contrast to or TRSAs as required by FAA Order JO 7110.65. prevailing or runway visibility, is based on what a VFR TERMINAL AREA CHARTS− pilot in a moving aircraft should see looking down the runway. RVR is horizontal visual range, not slant (See AERONAUTICAL CHART.) visual range. It is based on the measurement of a VFR WAYPOINT− transmissometer made near the touchdown point of (See WAYPOINT.) the instrument runway and is reported in hundreds of feet. RVR, where available, is used in lieu of VHF− prevailing visibility in determining minimums for a (See VERY HIGH FREQUENCY.) particular runway. VHF OMNIDIRECTIONAL RANGE/TACTICAL 1. Touchdown RVR− The RVR visibility AIR NAVIGATION− readout values obtained from RVR equipment (See VORTAC.) serving the runway touchdown zone. 2. Mid-RVR− The RVR readout values obtained VIDEO MAP− An electronically displayed map on from RVR equipment located midfield of the runway. the radar display that may depict data such as airports, 3. Rollout RVR− The RVR readout values heliports, runway centerline extensions, hospital obtained from RVR equipment located nearest the emergency landing areas, NAVAIDs and fixes, rollout end of the runway. reporting points, airway/route centerlines, bound- (See ICAO term FLIGHT VISIBILITY.) aries, handoff points, special use tracks, obstructions, (See ICAO term GROUND VISIBILITY.) prominent geographic features, map alignment (See ICAO term RUNWAY VISUAL RANGE.) indicators, range accuracy marks, and/or minimum (See ICAO term VISIBILITY.) vectoring altitudes. VISIBILITY [ICAO]− The ability, as determined by VISIBILITY− The ability, as determined by atmospheric conditions and expressed in units of atmospheric conditions and expressed in units of distance, to see and identify prominent unlighted distance, to see and identify prominent unlighted objects by day and prominent lighted objects by objects by day and prominent lighted objects by night.

PCG V−2 6/17/21 Pilot/Controller Glossary

a. Flight Visibility− The visibility forward from the MDA to the runway touchdown point may be the cockpit of an aircraft in flight. commenced, provided the approach threshold of that b. Ground Visibility− The visibility at an runway, or approach lights, or other markings aerodrome as reported by an accredited observer. identifiable with the approach end of that runway are clearly visible to the pilot. c. Runway Visual Range [RVR]− The range over which the pilot of an aircraft on the centerline of a VISUAL FLIGHT RULES− Rules that govern the runway can see the runway surface markings or the procedures for conducting flight under visual lights delineating the runway or identifying its conditions. The term “VFR” is also used in the centerline. United States to indicate weather conditions that are equal to or greater than minimum VFR requirements. VISUAL APPROACH− An approach conducted on In addition, it is used by pilots and controllers to an instrument flight rules (IFR) flight plan which indicate type of flight plan. authorizes the pilot to proceed visually and clear of (See INSTRUMENT FLIGHT RULES.) clouds to the airport. The pilot must, at all times, have (See INSTRUMENT METEOROLOGICAL either the airport or the preceding aircraft in sight. CONDITIONS.) This approach must be authorized and under the (See VISUAL METEOROLOGICAL control of the appropriate air traffic control facility. CONDITIONS.) Reported weather at the airport must be: ceiling at or (Refer to 14 CFR Part 91.) above 1,000 feet, and visibility of 3 miles or greater. (Refer to AIM.) (See ICAO term VISUAL APPROACH.) VISUAL HOLDING− The holding of aircraft at VISUAL APPROACH [ICAO]− An approach by an selected, prominent geographical fixes which can be IFR flight when either part or all of an instrument easily recognized from the air. approach procedure is not completed and the (See HOLDING FIX.) approach is executed in visual reference to terrain. VISUAL METEOROLOGICAL CONDITIONS− VISUAL APPROACH SLOPE INDICATOR Meteorological conditions expressed in terms of (VASI)− visibility, distance from cloud, and ceiling equal to or (See AIRPORT LIGHTING.) better than specified minima. (See INSTRUMENT FLIGHT RULES.) VISUAL CLIMB OVER AIRPORT (VCOA)− A (See INSTRUMENT METEOROLOGICAL departure option for an IFR aircraft, operating in CONDITIONS.) visual meteorological conditions equal to or greater (See VISUAL FLIGHT RULES.) than the specified visibility and ceiling, to visually VISUAL OBSERVER (VO)− A person who is conduct climbing turns over the airport to the designated by the remote pilot in command to assist published “climb−to” altitude from which to proceed the remote pilot in command and the person with the instrument portion of the departure. VCOA operating the flight controls of the small UAS procedures are developed to avoid obstacles greater (sUAS) to see and avoid other air traffic or objects than 3 statute miles from the departure end of the aloft or on the ground. runway as an alternative to complying with climb gradients greater than 200 feet per nautical mile. VISUAL SEGMENT− Pilots are responsible to advise ATC as early as (See PUBLISHED INSTRUMENT APPROACH possible of the intent to fly the VCOA option prior to PROCEDURE VISUAL SEGMENT.) departure. These textual procedures are published in VISUAL SEPARATION− A means employed by the ‘Take−Off Minimums and (Obstacle) Departure ATC to separate aircraft in terminal areas and en route Procedures’ section of the Terminal Procedures airspace in the NAS. There are two ways to effect this Publications and/or appear as an option on a Graphic separation: ODP. a. The tower controller sees the aircraft involved (See AIM.) and issues instructions, as necessary, to ensure that VISUAL DESCENT POINT− A defined point on the the aircraft avoid each other. final approach course of a nonprecision straight-in b. A pilot sees the other aircraft involved and upon approach procedure from which normal descent from instructions from the controller provides his/her own

PCG V−3 Pilot/Controller Glossary 6/17/21 separation by maneuvering his/her aircraft as VORTICES− Circular patterns of air created by the necessary to avoid it. This may involve following movement of an airfoil through the air when another aircraft or keeping it in sight until it is no generating lift. As an airfoil moves through the longer a factor. atmosphere in sustained flight, an area of area of low (See SEE AND AVOID.) pressure is created above it. The air flowing from the (Refer to 14 CFR Part 91.) high pressure area to the low pressure area around and about the tips of the airfoil tends to roll up into two VLF− rapidly rotating vortices, cylindrical in shape. These (See VERY LOW FREQUENCY.) vortices are the most predominant parts of aircraft VMC− wake turbulence and their rotational force is (See VISUAL METEOROLOGICAL dependent upon the wing loading, gross weight, and CONDITIONS.) speed of the generating aircraft. The vortices from VOICE SWITCHING AND CONTROL SYSTEM medium to super aircraft can be of extremely high (VSCS)− A computer controlled switching system velocity and hazardous to smaller aircraft. that provides air traffic controllers with all voice (See AIRCRAFT CLASSES.) circuits (air to ground and ground to ground) (See WAKE TURBULENCE.) necessary for air traffic control. (Refer to AIM.) (Refer to AIM.) VOR− A ground-based electronic navigation aid VOT− A ground facility which emits a test signal to transmitting very high frequency navigation signals, check VOR receiver accuracy. Some VOTs are 360 degrees in azimuth, oriented from magnetic available to the user while airborne, and others are north. Used as the basis for navigation in the National limited to ground use only. Airspace System. The VOR periodically identifies (See CHART SUPPLEMENT U.S.) itself by Morse Code and may have an additional (Refer to 14 CFR Part 91.) voice identification feature. Voice features may be (Refer to AIM.) used by ATC or FSS for transmitting instructions/information to pilots. VR− (See NAVIGATIONAL AID.) (See VFR MILITARY TRAINING ROUTES.) (Refer to AIM.) VOR TEST SIGNAL− VSCS− (See VOT.) (See VOICE SWITCHING AND CONTROL VORTAC− A navigation aid providing VOR SYSTEM.) azimuth, TACAN azimuth, and TACAN distance measuring equipment (DME) at one site. VTA− (See DISTANCE MEASURING EQUIPMENT.) (See VERTEX TIME OF ARRIVAL.) (See NAVIGATIONAL AID.) (See TACAN.) VTOL AIRCRAFT− (See VOR.) (See VERTICAL TAKEOFF AND LANDING (Refer to AIM.) AIRCRAFT.)

PCG V−4 6/17/21 Pilot/Controller Glossary W

WA− a. In conjunction with ATC instructions, gives the (See AIRMET.) pilot the latitude to delay compliance until a (See WEATHER ADVISORY.) condition or event has been reconciled. Unlike “pilot discretion,” when instructions are prefaced “when WAAS− able,” the pilot is expected to seek the first (See WIDE-AREA AUGMENTATION SYSTEM.) opportunity to comply. WAKE TURBULENCE− A phenomenon that occurs b. In conjunction with a weather deviation when an aircraft develops lift and forms a pair of clearance, requires the pilot to determine when he/she counter−rotating vortices. is clear of weather, then execute ATC instructions. (See AIRCRAFT CLASSES.) c. Once a maneuver has been initiated, the pilot is (See VORTICES.) expected to continue until the specifications of the instructions have been met. “When able,” should not (Refer to AIM.) be used when expeditious compliance is required. WARNING AREA− WIDE-AREA AUGMENTATION SYSTEM (See SPECIAL USE AIRSPACE.) (WAAS)− The WAAS is a satellite navigation system WAYPOINT− A predetermined geographical posi- consisting of the equipment and software which tion used for route/instrument approach definition, augments the GPS Standard Positioning Service progress reports, published VFR routes, visual (SPS). The WAAS provides enhanced integrity, reporting points or points for transitioning and/or accuracy, availability, and continuity over and above circumnavigating controlled and/or special use GPS SPS. The differential correction function airspace, that is defined relative to a VORTAC station provides improved accuracy required for precision or in terms of latitude/longitude coordinates. approach. WIDE AREA MULTILATERATION (WAM)– A WEATHER ADVISORY− In aviation weather distributed surveillance technology which may forecast practice, an expression of hazardous weather utilize any combination of signals from Air Traffic conditions not predicted in the Aviation Surface Control Radar Beacon System (ATCRBS) (Modes A Forecast, Aviation Cloud Forecast, or area forecast, and C) and Mode S transponders, and ADS-B as they affect the operation of air traffic and as transmissions. Multiple geographically dispersed prepared by the NWS. ground sensors measure the time-of-arrival of the (See AIRMET.) transponder messages. Aircraft position is deter- (See SIGMET.) mined by joint processing of the time-difference-of-arrival (TDOA) measurements WEATHER RECONNAISSANCE AREA (WRA)− computed between a reference and the ground A WRA is airspace with defined dimensions and stations’ measured time-of-arrival. published by Notice to Airmen, which is established to support weather reconnaissance/research flights. WILCO− I have received your message, understand Air traffic control services are not provided within it, and will comply with it. WRAs. Only participating weather reconnaissance/ WIND GRID DISPLAY− A display that presents the rd research aircraft from the 53 Weather latest forecasted wind data overlaid on a map of the Reconnaissance Squadron and National Oceanic and ARTCC area. Wind data is automatically entered and Atmospheric Administration Aircraft Operations updated periodically by transmissions from the Center are permitted to operate within a WRA. A National Weather Service. Winds at specific WRA may only be established in airspace within U.S. altitudes, along with temperatures and air pressure Flight Information Regions outside of U.S. territorial can be viewed. airspace. WIND SHEAR− A change in wind speed and/or wind WHEN ABLE− direction in a short distance resulting in a tearing or

PCG W−1 Pilot/Controller Glossary 6/17/21

shearing effect. It can exist in a horizontal or vertical a. As a request: “Communication is difficult. direction and occasionally in both. Please say every phrase twice.” WIND SHEAR ESCAPE− An unplanned abortive b. As information: “Since communications are maneuver initiated by the pilot in command (PIC) as difficult, every phrase in this message will be spoken a result of onboard cockpit systems. Wind shear twice.” escapes are characterized by maximum thrust climbs WS− in the low altitude terminal environment until wind (See SIGMET.) shear conditions are no longer detected. (See WEATHER ADVISORY.) WING TIP VORTICES− WST− (See VORTICES.) (See CONVECTIVE SIGMET.) WORDS TWICE− (See WEATHER ADVISORY.)

PCG W−2