CHAPTER 10 FLIGHT INSTRUMENTS Page TABLE OF CONTENTS 10-00-01/02 DESCRIPTION General 10-10-01 Description 10-10-01 Controls and Indicators 10-10-02 COMPONENTS (Not Used) CONTROLS AND INDICATORS 10-30-01 FUNCTIONAL SCHEMATICS Pitot/Static System 10-40-01/02 Central Air Data Computer/Pitot Static Interface 10-40-03/04 JL Feb 1/75 10-00-01/02 FLIGHT INSTRUMENTS GENERAL temperature and position error) raw data from the pitot static system. The over- The flight instruments chapter includes speed warning sensor will activate an the pitot static system, the air data sys- aural warning device when limiting air- tem, and those basic flight instruments, speeds are reached. standby instruments, and related com- ponents which provide altitude, airspeed, Mach, vertical speed, true airspeed, DIRECTIONAL INDICATING SYSTEMS over speed warning, attitude, and air temperature data to the flight crew. Sensors provide inputs to three central There are two independent compass sys- air data computers where temperature tems. Each compass system is stabi- and instrument position corrective fac- lized by the associated directional gyro tors are applied as appropriate. The or inertial navigation system (INS) plat- flight recorder maintains a history of form (if installed). The compass system time-related flight parameters. can operate in the slaved (normal) mode or DG (unslaved) mode. The mode is DESCRIPTION selected by the COMPASS switch on the overhead panel. In the slaved mode the PITOT/STATIC SYSTEM compass is synchronized with a flux valve and provides magnetic heading. During normal operation, the pitot/static The synchronization indicator is on the system inputs variable pressure values overhead panel. In the DG mode the to the central air data computers which compass heading is controlled by the provide computed outputs for readout of SET HDG knob on the overhead panel. airspeed, vertical speed, and altitude. The compass heading is displayed on the Two parallel static systems (the Cap- radio magnetic indicators (RMI) at all tain' s and First Officer's) provide inputs times, and on the horizontal situation to the central air data computers, while indicator (HSI) compass card when the a third system provides raw inputs HSI switch is in the RAD position. The (uncorrected barometric) to the standby number 1 compass system normally altimeter, the standby airspeed indicator, drives the Captain's HSI and the First and provides input to the third central air Officer's RMI. The number two compass data computer. A fourth (alternate static) system normally drives the First Officer's system provides raw inputs to the cabin HSI and the Captain's RMI. When the pressure controller and the cabin dif- COMP Selector on the overhead panel is ferential pressure indicator. placed in the BOTH ON 2 (or BOTH ON 1) position, the number two (or one) com- PRIMARY FLIGHT INSTRUMENTS pass system drives all compass cards. The adjacent annunciator light will be on. The primary Mach/AS indicators, true On aircraft with INS installed, when the airspeed indicators, vertical speed indi- HSI switch is in INS, the HSI compass cators, altimeters, and the over speed card will display true heading derived warning system derive their inputs from from the associated INS. A standby the central air data computers which magnetic compass provides a heading receive and process (correct for reference in relation to magnetic north. JL Feb 1/75 10-10-01 ATTITUDE DIRECTOR INDICATOR a test button which, when pushed, tests the attitude, flight director, and rising For the purpose of this chapter, the runway functions. Attitude Director Indicator (ADI) is con- sidered as a basic attitude display and DIGITAL FLIGHT DATA RECORDER not for the broader role it performs as the command focal point in the flight A digital flight data recorder (DFDR) director and flight guidance subsystems. records data from aircraft subsystems, These diverse aspects are described in sensors and flight data entry panel inputs. the navigation and flight guidance chapters. CONTROLS AND INDICATORS Two remote vertical gyros or inertial platforms (if installed) provide basic The controls, indicators, and annunciator attitude information to the Captain's and lights are on the Captains and First First Officer's ADI's. The ATT COMP Officers instrument panels, Center STAB selector permits selection of the instrument panel, Overhead panel, and third vertical gyro or the third inertial Flight Engineers Upper No. 2 and 3 platform (if installed) for input to either panels. Illustrations of the panels are the Captain's or First Officer's indicators. in Chapter 1. Individual controls and An ATT warning flag on the ADI indicates indicators are illustrated and described attitude data are unusable. The ADI has in this chapter. JL 10-10-02 Feb 1/79 FLIGHT INSTRUMENTS - Controls and Indicators MAX SPD WARN TEST Selector 1 —Rotating and holding switch momentarily will test Max Speed Warning System 1. An aural Altitude Advisory Light warning will sound. Works in conjunction with altitude ad- 2—Rotating and holding switch visory system. Provides steady on momentarily will test Max Speed signal (in conjunction with aural tone) Warning System 2. An aural when aircraft is at the altitude ad- warning will sound. visory threshold (minimum of 750 (OVERHEAD PANEL) feet from selected altitude) and goes off when within 250 feet of selected altitude. Advisory light flashes (in con- Altitude Warnings junction with aural tone) when air- The digital readout also displays an craft deviates 250 feet or more from OFF failure flag which is associated Digital Readout previously selected and acquired with either a loss of input power, in- Indicates altitude from 0 to 50,000 altitude. Pushing the altitude advisory valid computer input, no input for feet. The right-hand two-digit drum is RESET button will turn off the 2 +- 0.5 seconds or more, internal numbered in 20-foot increments. The flashing advisory light. power supply failure or other inter- "0" position of the left-hand ten- nal failures. The steady light can be turned off any thousands drum is green for alert in- time in flight by rotating the ALT pre- dication of altitudes of less than 10,000 select knob to set in new altitude. feet. FAILURE FLAG 100 Foot Pointer Altitude Reference Bugs (2) The pointer will make a full circle for Movable pointer used to alert pilot each 1000 ft. of altitude gained or to specified altitudes. lost. Negative altitudes are read on the dial as 900 feet for a - 100 foot altitude, et cetera. Pointer will remain in last position with power failure. NEG Flag A negative altitude shutter ob- BARO Set Knob scures the digital readout to annun- Push-to-turn BARO knob is rotated ciate altitudes below sea level. to change barometric pressure values as read in the MB/IN HG Reference Index Knob readouts. Used to set the altitude reference OFF Flag index as desired. ALTIMETER Appears to indicate mach data are unusable. Altitude MB/IN HG Readout Reference Indicates the selected barometric Index pressure as expressed in millibars and inches of mercury. Vmo Pointer Reads maximum permissible air- speed as related to altitude. Failure MACH Readout of the Vmo advisory system will Indicates mach number. The mini- drive the Vmo pointer to 257.5 kts. mum mach readout is .150. Normal static sea level indication is 350 knots. Airspeed Pointer A/S Flag Reads indicated airspeed. Failure of Appears when airspeed data are airspeed indicating system will cause unusable. pointer to remain in the last position. Airspeed Reference Bugs (4) Airspeed Command Bug MACH/AS INDICATOR Movable pointers normally used to alert the pilot to specified air- This bug reflects airspeed set in flight CAPTAIN'S AND COPILOT'S speeds. guidance SPD readout. INSTRUMENT PANELS JL Feb 1/87 10-30-01 McDonnell Douglas Corporation Proprietary Information - Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. FLIGHT INSTRUMENTS - Controls and Indicators OFF Flag TAS Readout Appears when TAS data are un- Indicates true airspeed, i.e., air- usuable In conjunction with flag, speed which is computer cor- failure warning codes are dis- rected for position error, played in the TAS readout. 111 temperature, and compressibility. indicates instrument failure, 999 If no computed data is received indicates loss of CADC digital for 2 seconds, instrument will dis- bus data. play it's lowest value, 130 knots. SAT Readout Indicates static air temperature OFF Flag in degrees centigrade Appears when SAT/TAT data are If no computed data is received unusable. In conjunction with for 2 seconds, last temperature flag, failure warning codes are displayed will be maintained in displayed in the SAT the SAT readout TAS/SAT INDICATOR readout: +11 indicates instru- (CENTER INSTRUMENT PANEL) ment failure, +99 indicates loss of CADC digital bus data. TAT Button Push to read total air temperature in the SAT readout Reading is independent of TAT on EPR/TAT readout (For description refer to Automatic Flight Chapter) ATTITUDE DIRECTOR INDICATOR (ADI) OFF Flag Appears when vertical speed data are unusable. Vertical Speed Pointer Indicates vertical speed in feet per minute VERTICAL SPEED INDICATOR CAPTAIN'S AND COPILOT'S INSTRUMENT PANELS JL 10-30-02 Feb 1/79 FLIGHT INSTRUMENTS - Controls and Indicators (For description, refer to Navigation System Chapter) HORIZONTAL SITUATION INDICATOR (HSI) CAPTAIN'S AND COPILOT'S INSTRUMENT PANELS JL Jun 1/96 10-30-03 FLIGHT INSTRUMENTS - Controls and Indicators Airplane Symbol Power Off Flag Indicates position of the airplane Appears when power is lost to the in- in relation to the horizon index. dicator or gyro failure Caging/Pitch Trim Control Turning the knob to C (climb) or D (dive) adjusts the airplane symbol up or down for pitch attitude ref- erence.