Part VI - General Operating and Flight Rules

Canadian Aviation Regulations (CARs) 2017-2

Standard 625 Schedule 4 - Helicopter Flight Data Recorder (FDR) Specifications

Content last revised: 2009/12/01

(amended 2009/12/01)

Parameters Range Installed System Minimum Accuracy (to recovered data)
Footnote 1
Sampling interval (in seconds) Resolution
read-out
Footnote 3
Relative Time (from recorded on prior to take-off) 8 hour minimum ±0.125% per hour 1 1 sec.
Indicated Airspeed Vmin to VD (KIAS) (minimum airspeed signal attainable with installed pitot-static system). ±5% or ±10 kt., whichever is greater. 1 1 kt.
Altitude -1,000 ft. to 20,000 ft. pressure altitude ±100 ft. to ±700 ft. (see table 1 in CAN-TSO C51-a)
1 25 to 150 ft.
Magnetic Heading 360° ±5° 1
Vertical acceleration -3g to +6g ±0.2g in addition to ±0.3g maximum datum 4 (or 1 per second where peaks, ref. to 1g, are recorded) 0.05g
Longitudinal acceleration ±1.0g ±1.5% max. range excluding datums error of ±5% 2 0.03g
Pitch attitude 100% of usable range ±2° 1 0. 8°
Roll attitude ±60° or 100% of usable range, whichever is greater ±2° 1 0. 8°
Altitude Rate ±8,000 fpm ±10% Resolution 250 fpm below 12,000 ft. indicated 1 250 fpm below 12,000

Engine Power, Each Engine

Parameters Range Installed System Minimum Accuracy (to recovered data)
Footnote 1
Sampling interval (in seconds) Resolution
read-out
Footnote 3
Main rotor speed

Free or power turbine

Engine Torque
Maximum range

Maximum range

Maximum range
±5%


±5%


±5%
1


1


1
1%Footnote 2


1%Footnote 2


1%Footnote 2

Flight Control, Hydraulic Pressure

Parameters Range Installed System Minimum Accuracy (to recovered data)
Footnote 1
Sampling interval (in seconds) Resolution
read-out
Footnote 3
Primary (discrete)

Secondary if applicable (discrete)
High/Low


High/Low
  1


1
 
Radio transmitter keying (discrete) On/Off   1  
Autopilot engaged (discrete) Engaged or disengaged   1  
SAS status - engaged (discrete) Engaged or disengaged Y 1  
SAS fault status (discrete) Fault/OK   1  

Flight Controls

Parameters Range Installed System Minimum Accuracy (to recovered data)
Footnote 1
Sampling interval (in seconds) Resolution
read-out
Footnote 3
Collective Pedal position

Lateral cyclic

Longitudinal cyclic

Controllable stabilator position
Full range



Full range


Full range


Full range
±3%



±3%


±3%


±3%
2



2


2


2
±1% Footnote 2



±1% Footnote 2


±1% Footnote 2


±1% Footnote 2
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