Appendix B - Appendix B to Part 121—Airplane Flight Recorder Specification

Parameters Range Accuracy sensor input to DFDR readout Sampling interval (per second) Resolution 4 readout Time (GMT or Frame Counter) (range 0 to 4095, sampled 1 per frame)24 Hrs±0.125% Per Hour0.25 (1 per 4 seconds)1 sec. Altitude−1,000 ft to max certificated altitude of aircraft±100 to ±700 ft (See Table 1, TSO-C51a)15′ to 35′ 1Airspeed50 KIAS to V so, and V so to 1.2VD±5%, ±3%11 kt. Heading360°±2°10.5° Normal Acceleration (Vertical)−3g to + 6g±1% of max range excluding datum error of ±5%80.01g. Pitch Attitude±75°±2°10.5° Roll Attitude±180°±2°10.5° Radio Transmitter KeyingOn-Off (Discrete)±2°±2%Thrust/Power on Each EngineFull Range Forward±2°1 (per engine)0.2% 2Trailing Edge Flap or Cockpit Control SelectionFull Range or Each Discrete Position±3° or as Pilot's Indicator0.50.5% 2Leading Edge Flap or Cockpit Control SelectionFull Range or Each Discrete Position±3° or as Pilot's Indicator0.50.5% 2Thrust Reverser PositionStowed, In Transit, and Reverse (Discrete)1 (per 4 seconds per engine)Ground Spoiler Position/Speed Brake SelectionFull Range or Each Discrete Position±2% Unless Higher Accuracy Uniquely Required10.2% 2. Marker Beacon PassageDiscrete1Autopilot EngagementDiscrete1Longitudinal Acceleration±1g±1.5% max range excluding datum error of ±5%40.01g. Pilot Input and/or Surface Position—Primary Controls (Pitch, Roll, Yaw) 3Full Range±2° Unless Higher Accuracy Uniquely Required10.2% 2. Lateral Acceleration±1g±1.5% max range excluding datum error of ±5%40.01g. Pitch Trim PositionFull Range±3% Unless Higher Accuracy Uniquely Required10.3% 2. Glideslope Deviation±400 Microamps±3%10.3% 2. Localizer Deviation±400 Microamps±3%10.3% 2. AFCS Mode and Engagement StatusDiscrete1Radio Altitude−20 ft to 2,500 ft±2 Ft or ±3% Whichever is Greater Below 500 Ft and ±5% Above 500 Ft11 ft + 5% 2 above 500′. Master WarningDiscrete1Main Gear Squat Switch StatusDiscrete1Angle of Attack (if recorded directly).As installedAs installed20.3% 2Outside Air Temperature or Total Air Temperature.−50 °C to + 90 °C±2 °c0.50.3 °c Hydraulics, Each System Low PressureDiscrete0.5or 0.5% 2Groundspeed.As installedMost Accurate Systems Installed (IMS Equipped Aircraft Only)10.2% 2If additional recording capacity is available, recording of the following parameters is recommended. The parameters are listed in order of significance: Drift AngleWhen available, As installedAs installed4Wind Speed and DirectionWhen available, As installedAs installed4Latitude and LongitudeWhen available, As installedAs installed4Brake pressure/Brake pedal positionAs installedAs installed1Additional engine parameters: EPRAs installedAs installed1 (per engine).N1As installedAs installed1 (per engine).N2As installedAs installed1 (per engine).EGTAs installedAs installed1 (per engine).Throttle Lever PositionAs installedAs installed1 (per engine).Fuel FlowAs installedAs installed1 (per engine).TCAS: TAAs installedAs installed1RAAs installedAs installed1Sensitivity level (as selected by crew)As installedAs installed2GPWS (ground proximity warning system)Discrete1Landing gear or gear selector positionDiscrete0.25 (1 per 4 seconds)DME 1 and 2 Distance0-200 NM;As installed0.251 mi. Nav 1 and 2 Frequency SelectionFull rangeAs installed0.25

1 When altitude rate is recorded. Altitude rate must have sufficient resolution and sampling to permit the derivation of altitude to 5 feet.

2 Per cent of full range.

3 For airplanes that can demonstrate the capability of deriving either the control input on control movement (one from the other) for all modes of operation and flight regimes, the “or” applies. For airplanes with non-mechanical control systems (fly-by-wire) the “and” applies. In airplanes with split surfaces, suitable combination of inputs is acceptable in lieu of recording each surface separately.

4 This column applies to aircraft manufactured after October 11, 1991.

[Doc. No. 25530, 53 FR 26147, July 11, 1988; 53 FR 30906, Aug. 16, 1988]