Standard 625 Schedule 5: Helicopter Digital Flight Data Recorder (DFDR) Specifications - Canadian Aviation Regulations (CARs)

Content last revised: 2009/12/01
(amended 2009/12/01)

Parameters Range Accuracy sensor input to DFDR readout Sampling interval (in seconds) Resolution read-outFootnote 2
Time (GMT) 24 hrs ±0.125% per hour 0.25 (1 per 4 seconds) 1 sec.
Altitude -1,000 ft. to maximum certificated altitude of aircraft ±100 ft. to ±700 ft. (See table 1 in CAN-TSO-C51a) 1 5 ft. to 30 ft.
Airspeed As the installed measuring system ±3% 1 1kt
Heading 360° ±2° 1 0.5°
Normal (vertical) acceleration -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%Footnote 1 to
0.4%Footnote 1
Main Rotor Speed 0 - 130% ±2% 2 0.3%Footnote 1
Altitude rate ±6,000 ft/min As installed 2 0.2%Footnote 1
Pilot Input - primary controls (collective, longitudinal cyclic, lateral cyclic, pedal) full range ±3% 2 0.5%Footnote 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%Footnote 1
Main Gearbox Temperature High As installed As installed 0.5 0.5%Footnote 1
Controllable Stabilator Position full range ±3% 2 0.4%Footnote 1
Longitudinal acceleration ±1g ±1.5% of max range excluding datum error of ±5% 4 0.01g
Lateral acceleration ±1g ±1.5% of max range excluding datum error 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