Service difficulty report · Servo Valve · Snias AS350BA

Difficulty date
January 17, 2000
Submitted
January 22, 2001
Operation
Air carrier
Make and model
Snias AS350BA
Aircraft time
2,912 hours
Engine
Tmeca ARRIEL1B
Part
Servo Valve
Part number
ACM29029
Condition
Failed
Location
Actuator
Part time
2,895 hours
Component
Actuator · Dunlop · AC67032
Stage of operation
AP
How discovered
O
Nature of condition
F
Precautionary procedure
H

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

(CAN) DURING PILOT PROFICIENCY CHECK, A SIMULATED EMERGENCY WAS CONDUCTED, SPECIFICALLY STUCK RIGHT ANTI-TORQUE PEDAL IN FLIGHT. RECOMMENDED EMERGENCY PROCEDURE WAS INITATED IAW AFM. UPON ACTIVATION OF THE HYD TEST BUTTON WHICHBROUGHT THE PEDALS TO NEUTRAL OR LOW PITCH INITIALLY, THE PEDALS RETURNED TO THEIR HIGH PITCH (RIGHT) POSITION AFTER THE TEST BUTTON WAS RELEASED AFTER THE STATED 5 SECOND INTERVAL WHICH IS CONTRARY TO NORMAL OPERATION FOR THIS AIRCRAFT. LEAVING THE SWITCH ACTIVATED FOR LONGER THAN THE RECOMMENDED 5SECONDS WOULD RESULT IN THE ACCUMULATORS DEPLETING THEMSELVES AND RESULT INHYDRAULIC FAILURE.