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Pt. 135, App. E
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]