14 CFR Appendix E to Part 135 - Appendix E to Part 135—Helicopter Flight Recorder Specifications

Appendix E to Part 135—Helicopter Flight Recorder Specifications
Parameters Range Accuracy sensor input to DFDR readout Sampling interval (per second) Resolution 2 read out
Time (GMT) 24 Hrs ±0.125% Per Hour 0.25 (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) 1 5′ to 30′.
Airspeed As the installed measuring system ±3% 1 1 kt
Heading 360° ±2° 1 0.5°.
Normal Acceleration (Vertical) −3g to + 6g ±1% of max range excluding datum error of ±5% 8 0.01g
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 Turbine Speed and Engine Torque 0–130% (power Turbine Speed) Full range (Torque) ±2% 1 speed 1 torque (per engine) 0.2% 1 to 0.4% 1
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 (Collective, Longitudinal Cyclic, Lateral Cyclic, Pedal) 3 Full range ±3% 2 0.5% 1
Flight Control Hydraulic Pressure Low Discrete, each circuit 1
Flight Control Hydraulic Pressure Selector Switch Position, 1st and 2nd stage Discrete 1
AFCS Mode and Engagement Status Discrete (5 bits necessary) 1
Stability Augmentation System Engage Discrete 1
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 range excluding datum error of ±5% 4 0.01g.
Lateral Acceleration ±1g ±1.5% max range excluding datum of ±5% 4 0.01g.
Master Warning Discrete 1
Nav 1 and 2 Frequency Selection Full range As installed 0.25
Outside Air Temperature −50 °C to + 90 °C ±2° c 0.5 0.3° c

1 Per cent of full range.

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

3 For all aircraft manufactured on or after December 6, 2010, the sampling interval per second is 4.

[Doc. No. 25530, 53 FR 26154, July 11, 1988; 53 FR 30906, Aug. 16, 1988; Amdt. 135–113, 73 FR 12571, Mar. 7, 2008; 73 FR 15281, Mar. 21, 2008; Amdt. 135–121, 75 FR 17047, Apr. 5, 2010]