Service difficulty report · Planetary Gear

Difficulty date
October 7, 2004
Submitted
March 3, 2005
Operation
General aviation
Engine
Pwa PT6A28
Part
Planetary Gear
Condition
Failed
Location
Engine
Stage of operation
IN
How discovered
9
Nature of condition
O
Precautionary procedure
K

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

What was found

(CAN) ENG REMOVED DUE TO METAL IN OIL. ENG SENT IN FOR INVEST & REPAIR. CUSTOMER DECIDED TO SEND ALL PARTS OF ENG TO OUR AMO FOR REVIEW. SOURCE OF METAL FROM A 2ND STAGE PLANETARY GEAR BEARING SLEEVE FAILURE. BRONZE PARTICLES GENERATED FROM SLEEVE BEARING BRONZE FACE DURING SEIZURE. SLEEVE SEIZED ONTO THE SHAFT - GEAR OVERCAME RESISTANCE OF GEAR/SLEEVE TIGHT FIT & GEAR STARTED TO TURN AROUND SLEEVE ON SLEEVE OUTSIDE SURFACE. ROTATION GENERATED METAL PARTICLES FROM GEAR BORE AND SLEEVE. ALL OF THE OIL STRAINERS IN BOTH 1ST & 2ND STAGE CARRIERS FOUND TO BE PARTIALLY BLOCKED. SEIZURE RELATED TO OIL STARVATION CAUSED BY THE BLOCKED STRAINERS.