Appendix D to Part 135 - Airplane Flight Recorder Specification
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                                                        Accuracy sensor
           Parameters                    Range           input to DFDR     Sampling interval    resolution \4\
                                                            readout          (per second)          read out
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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[foot] to
                                   certificated        700 ft (See                       35[foot] \1\.
                                   altitude of         Table 1, TSO-
                                   aircraft.           C51a).
Airspeed........................  50 KIAS to          5%, 3%  1.................  1kt
                                   V[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).  ..................  1.................  ..................
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 on 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
                                   (discretion).
Ground Spoiler Position/Speed     Full range or each  2% unless     1.................  0.22 \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)....  ..................
    N \1\.......................  As installed......  As installed......  1 (per engine)....  ..................
    N \2\.......................  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..............  1mi.
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 26153, July 11, 1988; 53 FR 30906, Aug. 16, 1988]