Service difficulty report · Propeller · Dhav DHC8311

Difficulty date
November 7, 2013
Submitted
September 14, 2015
Operation
General aviation
Make and model
Dhav DHC8311
Aircraft time
51,804 hours
Engine
Pwa PW123
Propeller
Hamstd 14SF*
Part
Propeller
Condition
Malfunctioned
Stage of operation
CL
How discovered
O
Nature of condition
J
Precautionary procedure
E, A

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

What was found

(CAN) DURING TAKEOFF ROTATION, THE NR 1 PROPELLER FEATHERED. THE TORQUE RAPIDLY INCREASED ABOVE NORMAL OPERATING LIMIT AND FLIGHT CREW SHUTDOWN THE ENGINE. AN EMERGENCY WAS DECLARED AND THE ACFT RETURNED, LANDED WITHOUT FURTHER INCIDENT. SOLID STATE FLIGHT DATA RECORDER, SSFDR, WAS DOWNLOADED AND ENGINE DATA FORWARDED TO THE ENGINE MFG. SSFDR DATA ANALYSIS CONFIRMED THE OVERTORQUE,132.4 PERCENT FOR 133 SECONDS. CONDITION COULDN`T BE DUPLICATED ON GROUND. TROUBLESHOOTING REVEALED SOME CONTAMINATION AT THE NR 1 TORQUE SIGNAL CONDITIONER UNIT, TSCU, ELECTRICAL CONNECTORS. THE NR 1 ENGINE TSCU, ELECTRONIC ENGINE CONTROL UNIT, EECU AND THE TORQUE PROBE WERE REPLACED AND TESTED SERVICEABLE. AS A RESULT OF THE OVERTORQUE EVENT, THE NR 1 PROPELLER ASSY WAS REPLACED AND THE ENGINE INSPECTED IAW ASSOCIATED COMPONENT MM, CHAPTER 05. ACFT TIMES AT THE TIME OF THE INCIDENT, 51612 FLIGHT HOURS AND 64695 CYCLES.