MITMIT ICATICAT Altimetry y Standard Atmosphere Referenced 29.92 inches of Hg 3014 mb y Pressure Altitude Altitude of Pressure in Std Atmosphere Used above reference Flight Level (FL180 in US) y Density Altitude Altitude of density in Std Atmosphere Used for performance (TO) y Barometric Altitude Estimated altitude corrected for surface pressure MSL Altitude above Mean Sea Level (QNH) AGL Altitude above Ground Level (QFE) y Radar Altitude (Cat II and III Approaches) 5 cm radar - normally only below 3000ft (Terrain Noise) y Cabin Altitude (Pressurization) MITMIT ICATICAT Airspeed y Pneumatic Measurement based on Dynamic Pressure Pitot and Static y Indicated Airspeed Indicated on Instrument Measurement of pressure on Aircraft (ie Load) Used for structural operating limits y Calibrated Airspeed Pitot-Static Errors Calibrated out Used for Flight Test and Performance y Groundspeed Achieved speed over ground y Mach Number Requires Static Air Temperature MITMIT Air Data Sensors ICATICAT y Pitot Tube Heated for De-Ice y Static Port Location Sensitive Typically 1/3 Back on Fuselage on Conventional aircraft Bilateral with crosstie to avoid Side Slip Errors Water Drain y Alpha Vane Heated for De-Ice y TAT Probe Inertial Separator for Water Heated for De-Ice MITMIT Temperature ICATICAT y Static Air Temperature y Ram Rise y Total Air Temperature MITMIT Integrated Air Data Systems ICATICAT y Air Data Computer Compensates out Static System Errors Citation Example y Air Data Heading and Reference Systems (ADHARS) MITMIT Heading ICATICAT y Magnetic Compass Variation (Magnetic Deviation Deviation (Magnetic materials) DC9 Example Compass Card (Calibrated with Radios and Equip on) y Flux Gate Compass Electronic Magnetic Compass Normally in Tail for deviation y Gyro Compass Precession Slaved Flux Gate y Turn Coordinator (Rate Gyro) MITMIT Inertial Reference Unit ICATICAT y Integrate acceleration from known position and velocity Velocity Position y Need Heading Gyros Mechanical Laser y Can get Attitude Artificial Horizon (PFD. HUD) y Drift Errors IRU unusable in vertical direction (need baro alt) Inflight Correction DME GPS Star Sighting for Space Vehicles y Measurement Give Attitude Also y 777 Analytical Redundancy MITMIT Communications ICATICAT y Requirements Communicate necessary information between formation elements and command node (LAN and Air-Ground) Bandwidth Low-Observable? Synchronous vs asynchronous y Constraints Spectrum Antenna Location y Technologies Radio UHF, VHF, MMW Optical Laser Protocols MITMIT ICATICAT COMMUNICATION y Voice VHF (line of sight) 118.0-135.0 Mhz .025 spacing in US, 0.083 spacing in Europe) UHF 230-400 Mhz (guess) HF (over the horizon) Optical (secure) y Datalink ACARS (VHF) - VDL Mode 2 VDL Modes 3 and 4 (split voice and data) HF Datalink (China and Selcal) y Geosynchronous (Inmarsatt) Antenna Requirements y LEO and MEO Networks y Software Radios y Antenna Requirements MITMIT Bandwidth Growth Trend ICATICAT Source: DOD UAV Roadmap, 2000 MITMIT Navigation ICATICAT (relates to Surveillance) y Requirements General Navigation (medium precision) Station Keeping (high precision) Integrity Availability y Constraints Existing nav systems Loss of signal y Technologies GPS/Galileo (need Differential) Code vs Carrier Phase Approaches IRS/GPS Sensor Based Approaches for Station Keeping Image (Visible, IR) Range Finders (Laser, Ultrasonic) MITMIT ICATICAT NAVIGATION (ENROUTE) y Radionavigation beacon VHF Omnidirectional Range (VOR) Non-Directional Beacon (NDB) Distance Measuring Equipment (DME) TACAN y Area navigation systems (ground based) Omega LORAN y Inertial navigation systems y Satellite navigation systems GPS (CA) GNSS (Galileo?) MITMIT GPS ICATICAT (Courtesy of Peter Dana. Used with permission.) From http://www.Colorado.Edu/geography/gcraft/notes/gps/gps_f.html MITMIT GPS ICATICAT Courtesy of Peter H. Dana, The Geographer's Craft Project, Department of Geography, The University of Colorado at Boulder. Used with permission. From http://www.colorado.Edu/geography/gcraft/notes/gps/gps_f.html MITMIT GPS ISSUES ICATICAT y Requirements Accuracy Integrity Availability y Selective Availability (SA) Degraded to 100m accuracy y Control by US DoD International concerns y US guarantee of service free to world through 2005 y Vulnerability to jamming y DGPS WAAS EGNOS LAAS MITMIT NAVIGATION TRENDS ICATICAT (APPROACH) y Instrument Landing System (ILS) Cat. I (200 ft; 1/4 mile) Cat. II (50 ft; 800 RVR) Cat. III (0,0) y Microwave Landing System (MLS) y GPS (100m) Wide Areas Augmentation System (5m) LNAV-VNAV (250, 1/4 mile) Local Area Augmentation System (0.1m) Cat. III? y Change to Required Navigation Performance (RNP) RNP X X is 95% lateral containment on NM MITMIT NAVIGATION TRENDS ICATICAT (APPROACH) MITMIT NAVIGATION TRENDS ICATICAT (APPROACH) MITMIT GPS Approach Navigation ICATICAT y Requirements Accuracy (RNP) Availability Integrity y Differential GPS Wide Area Augmentation System (WAAS) Local Area Augmentation System (LAAS) MITMIT Surveillance ICATICAT y Requirements Observed states of lead elements sufficient to form-up and maintain Feed forward states (intent) y Constraints Sight Angles Installation (weight, cost, power, etc) Cooperative Targets y Technologies Automatic Dependant Surveillance Broadcast (ADS-B) Image Based Systems (Vis, IR) Radar (X Band, MMW0 Range Finders (Laser) Sensor Fusion Systems MITMIT ICATICAT RADAR y Weather Radar (10 CM) y Search and Track Doppler y Synthetic Aperture Radar y Radar Altimeter MITMIT ICATICAT RADAR y Wavelength λ S Band (10 cm) X Band (3 cm) Ku Band (1 (cm) Millimeter Wave (94 Ghz pass band) y Radar Range Equation y Beamwidth Θ Θ = λ/D D = Diameter of Circular Antenna Pencil beam vs Fan Beam y Mechanically Steered Antennas Scan and Tilt MITMIT Imaging and Night Vision Systems ICATICAT y Infrared Special Optics (eg Gallium Arsinide) Water Contamination Sensor Cooling Requirements y Image Intensifier Systems y Pointing Systems MITMIT Datalink Based Systems ICATICAT y JTIDS y Mode S Transponders Traffic Information Service y ADS-B MITMIT Self Reporting Aircraft States ICATICAT ADS-B (Image removed due to copyright considerations.) Bob Hilb UPS/Cargo Airline Association MITMIT INTENT REPRESENTATION ICATICAT (consider other states) y Intent formalized in “Surveillance State Vector” ⎧ Position states, P(t) ⎫ ⎪ Velocity states, V(t) ⎪ Traditional dynamic ⎪ ⎪ states Surveillance State ⎪ Acceleration states, A(t) ⎪ = ⎨ ⎬ Vector, X(t) Current target states, C(t) ⎪ ⎪ Defined intent ⎪Planned trajectory states, T(t)⎪ ⎪ ⎪ states ⎩⎪ Destination states, D(t) ⎭⎪ y Accurately mimics intent communication & execution in ATC MCP Current target state, C(t) Planned PILOT FMS trajectory, T(t) Destination, D(t) MITMIT ADS-B SURVEILLANCE ICATICAT ENVIRONMENT y Potential access to more states (e.g. dynamic and intent) y Need to assess benefits for conformance monitoring ACTUAL SYSTEM REPRESENTATION PILOT A/C CONTROL AIRCRAFT INTENT INTENT SYSTEM DYNAMICS Trajectory, Target Nav. Control A/c Position, P(t) Destination states, accuracy surface property Velocity, V(t) Guidance e.g. ANP inputs e.g. weight Accel., A(t) mode ADS-B SURVEILLANCE SYSTEM Position, Trajectory Target Other useful states states??? Baro altitude Heading, Speeds Roll, ... MITMIT Engine Instrumentation ICATICAT y Rotation Rates N1 y Exhaust Pressure Ratio y Temperatures Turbine Inlet Temperature y Oil Pressure y Oil Temp y Vibration MITMIT Warning Systems ICATICAT y Master Caution Fire Low Pressure (eg oil) … y Stall Warning Stick Shaker y Traffic Collision Avoidance System (TCAS) y Enhanced Ground Proximity Warning System (EGPWS) y Envelope Protection MITMIT Envelope Protection ICATICAT Fly-by-wire protection - Normal Law Pitch Load Bank attitude factor angle Ground Takeoff FlightFlight Flare Ground mode mode modemode mode mode High Overspeed *AOA * Angle of Attack (AOA) MITMIT High Angle of Attack ICATICAT Protection Airspeed scale CL CL 140 VLS Vα Prot Vα Floor α Angle of Attack (AOA) 120 Vα Max α Stall: Sudden loss of lift and or aircraft control α Max: Angle of attack reached with full aft stick (max aircraft performance) α Floor: Angle of attack, where TOGA thrust is automatically applied by the A/THR α Prot: Angle of attack from which stick input is converted into angle of attack demand (stick neutral α Prot) α VLS: Angle of attack reached at approach speed (VLS).