Appendix E to Part 135 - Helicopter Flight Recorder Specifications
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                                                        Accuracy sensor
           Parameters                    Range           input to DFDR     Sampling interval    Resolution \2\
                                                            readout          (per second)          read out
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Time (GMT)......................  24 Hrs............  0.125% Per    0.25 (1 per 4       1 sec
                                                       Hour.               seconds).
Altitude........................  -1,000 ft to max    100 to        1.................  5[foot] to
                                   certificated        700 ft (See                       30[foot].
                                   altitude of         Table 1, TSO-
                                   aircraft.           C51a).
Airspeed........................  As the installed    3%..........  1.................  1 kt
                                   measuring system.
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.....  2.................  0.5
Roll Attitude...................  180...  2.....  2.................  0.5.
Radio Transmitter Keying........  On-Off (Discrete).  ..................  1.................  0.25 sec
Power in Each Engine: Free Power  0-130% (power       2%..........  1 speed 1 torque    0.2% \1\ to 0.4%
 Turbine Speed and Engine Torque.  Turbine Speed)                          (per engine).       \1\
                                   Full range
                                   (Torque).
Main Rotor Speed................  0-130%............  2%..........  2.................  0.3% \1\
Altitude Rate...................  6,000 ft/min  As installed......  2.................  0.2% \1\
Pilot Input_Primary Controls      Full range........  3%..........  2.................  0.5% \1\
 (Collective, Longitudinal
 Cyclic, Lateral Cyclic, Pedal).
Flight Control Hydraulic          Discrete, each      ..................  1.................  ..................
 Pressure Low.                     circuit.
Flight Control Hydraulic          Discrete..........  ..................  1.................  ..................
 Pressure Selector Switch
 Position, 1st and 2nd stage.
AFCS Mode and Engagement Status.  Discrete (5 bits    ..................  1.................  ..................
                                   necessary).
Stability Augmentation System     Discrete..........  ..................  1.................  ..................
 Engage.
SAS Fault Status................  Discrete..........  ..................  0.25..............  ..................
Main Gearbox Temperature Low....  As installed......  As installed......  0.25..............  0.5% \1\
Main Gearbox Temperature High...  As installed......  As installed......  0.5...............  0.5% \1\
Controllable Stabilator Position  Full Range........  3%..........  2.................  0.4% \1\.
Longitudinal Acceleration.......  1g..........  1.5% max      4.................  0.01g.
                                                       range excluding
                                                       datum error of
                                                       5%.
Lateral Acceleration............  1g..........  1.5% max      4.................  0.01g.
                                                       range excluding
                                                       datum of 5%.
Master Warning..................  Discrete..........  ..................  1.................  ..................
Nav 1 and 2 Frequency Selection.  Full range........  As installed......  0.25..............  ..................
Outside Air Temperature.........  -50 C to      2 c...  0.5...............  0.3 c
                                   +90 C.
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\1\ Per cent of full range.
\2\ This column applies to aircraft manufactured after October 11, 1991.

[Doc. No. 25530, 53 FR 26154, July 11, 1988; 53 FR 30906, Aug. 16, 1988]