Guimbal CABRI G2 Flight Manual page 155

Hélicoptères Guimbal
CABRI G2
Behavioral symptoms of sensor failure
If the throttle sensor sends an erroneous signal within the nominal range, no
display will warn the pilot.
In that case, the engine governor may produce oscillations of the throttle and
the engine speed when the rotor is desynchronized. If not interrupted by the
pilot, the engine speed may decrease below 2000 RPM and stay there (engine
governor deactivation).
However, in normal powered flight, engine governor behavior is nominal
In case of a sensor failure, the pilot should then resynchronize and keep the
rotor powered:
1. Oscillations happen in flight:
Apply Flight Manual procedure page 3-9 :
1. Hold the twist grip firmly, and overtake the governor action,
2. Switch governor OFF,
3. Regulate rotor/engine speed in the middle of green arc with
twist grip,
4.
CONTINUE FLIGHT
2. When the rotor is synchronized, the governor may be switched back
ON to resume normal governed flight. Avoid intentional maneuvers
that could lead to desynchronization of rotor/engine:
- Steep descent with low collective setting,
- Quick stop or other similar maneuver, especially close to the
ground.
If such maneuver should still be undertaken, switch-off the governor
beforehand and control the power manually using the twist grip to
keep the rotor/engine speed in the green arc.
3. Report any sensor failure as described above to the helicopter
maintenance manager
Warning : When switching governor back ON, be prepared to switch it off again
as indicated above, in case the failure is different from the one described in this
Service Letter.
Original issue
even with a failed throttle position sensor.
SERVICE LETTER
SL 15-001 A
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