FAA Federal Aviation Regulations (FARS, 14 CFR)

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Accuracy sensor
Parameters                    Range           input to DFDR     Sampling interval    Resolution \4\
readout          (per second)           readout
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Time (GMT or Frame Counter)       24 Hrs............  ±0.125% Per    0.25 (1 per 4       1 sec.
(range 0 to 4095, sampled 1 per                       Hour.               seconds).
frame).
Altitude........................  -1,000 ft to max    ±100 to        1.................  5[min] to 35[min]
certificated        ±700 ft (See                       \1\
altitude of         Table 1, TSO-
aircraft.           C51a).
Airspeed........................  50 KIAS to V        ±5%, ±3%  1.................  1 kt.
[INF]so[/INF],
and V [INF]so[/
INF] to 1.2
V[INF]D[/INF].
Heading.........................  360°.........  ±2°.....  1.................  0.5°
Normal Acceleration (Vertical)..  -3g to +6g........  ±1% of max     8.................  0.01g.
range excluding
datum error of
±5%.
Pitch Attitude..................  ±75°....  ±2°.....  1.................  0.5°
Roll Attitude...................  ±180°...  ±2°.....  1.................  0.5°
Radio Transmitter Keying........  On-Off (Discrete).  ±2°.....  ±2%..........  ..................
Thrust/Power on Each Engine.....  Full Range Forward  ±2°.....  1 (per engine)....  0.2% \2\
Trailing Edge Flap or Cockpit     Full Range or Each  ±3° or    0.5...............  0.5% \2\
Control Selection.                Discrete Position.  as Pilot's
Indicator.
Leading Edge Flap or Cockpit      Full Range or Each  ±3° or    0.5...............  0.5% \2\
Control Selection.                Discrete Position.  as Pilot's
Indicator.
Thrust Reverser Position........  Stowed, In          ..................  1 (per 4 seconds    ..................
Transit, and                            per engine).
Reverse
(Discrete).
Ground Spoiler Position/Speed     Full Range or Each  ±2% Unless     1.................  0.2% \2\.
Brake Selection.                  Discrete Position.  Higher Accuracy
Uniquely Required.
Marker Beacon Passage...........  Discrete..........  ..................  1.................  ..................
Autopilot Engagement............  Discrete..........  ..................  1.................  ..................
Longitudinal Acceleration.......  ±1g..........  ±1.5% max      4.................  0.01g.
range excluding
datum error of
±5%.
Pilot Input and/or Surface        Full Range........  ±2°       1.................  0.2% \2\.
Position_Primary Controls                             Unless Higher
(Pitch, Roll, Yaw) \3\.                               Accuracy Uniquely
Required.
Lateral Acceleration............  ±1g..........  ±1.5% max      4.................  0.01g.
range excluding
datum error of
±5%.
Pitch Trim Position.............  Full Range........  ±3% Unless     1.................  0.3% \2\.
Higher Accuracy
Uniquely Required.
Glideslope Deviation............  ±400           ±3%..........  1.................  0.3% \2\.
Microamps.
Localizer Deviation.............  ±400           ±3%..........  1.................  0.3% \2\.
Microamps.
AFCS Mode and Engagement Status.  Discrete..........  ..................  1.................  ..................
Radio Altitude..................  -20 ft to 2,500 ft  ±2 Ft or       1.................  1 ft + 5% \2\
±3%                                above 500[foot].
Whichever is
Greater Below 500
Ft and ±5%
Above 500 Ft.
Master Warning..................  Discrete..........  ..................  1.................  ..................
Main Gear Squat Switch Status...  Discrete..........  ..................  1.................  ..................
Angle of Attack (if recorded      As installed......  As installed......  2.................  0.3% \2\
directly)..
Outside Air Temperature or Total  -50° C to      ±2° c...  0.5...............  0.3° c
Air Temperature..                 +90° C.
Hydraulics, Each System Low       Discrete..........  ..................  0.5...............  or 0.5% \2\
Pressure.
Groundspeed.....................  As installed......  Most Accurate       1.................  0.2% \2\
Systems Installed
(IMS Equipped
Aircraft Only).
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If additional recording capacity is available, recording of the following parameters is recommended. The
parameters are listed in order of significance:
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Drift Angle.....................  When available, As  As installed......  4.................  ..................
installed.
Wind Speed and Direction........  When available, As  As installed......  4.................  ..................
installed.
Latitude and Longitude..........  When available, As  As installed......  4.................  ..................
installed.
Brake pressure/Brake pedal        As installed......  As installed......  1.................  ..................
position.
Additional engine parameters:
EPR.........................  As installed......  As installed......  1 (per engine)....  ..................
N1..........................  As installed......  As installed......  1 (per engine)....  ..................
N2..........................  As installed......  As installed......  1 (per engine)....  ..................
EGT.........................  As installed......  As installed......  1 (per engine)....  ..................
Throttle Lever Position.........  As installed......  As installed......  1 (per engine)....  ..................
Fuel Flow.......................  As installed......  As installed......  1 (per engine)....  ..................
TCAS:
TA..........................  As installed......  As installed......  1.................  ..................
RA..........................  As installed......  As installed......  1.................  ..................
Sensitivity level (as         As installed......  As installed......  2.................  ..................
selected by crew).
GPWS (ground proximity warning    Discrete..........  ..................  1.................  ..................
system).
Landing gear or gear selector     Discrete..........  ..................  0.25 (1 per 4       ..................
position.                                                                 seconds).
DME 1 and 2 Distance............  0-200 NM;.........  As installed......  0.25..............  1 mi.
Nav 1 and 2 Frequency Selection.  Full range........  As installed......  0.25..............  ..................
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\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]