Service difficulty report · Pinion Gear

Difficulty date
April 18, 2000
Submitted
July 5, 2000
Operation
General aviation
Engine
Pwa PW123D
Part
Pinion Gear
Part number
311657901
Condition
Spalled
Location
2nd Stg Pinion
Part time
33,700 hours, 46,960 cycles
Component
Rgb · Pwa
Stage of operation
IN
How discovered
V
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) GEAR TEETH ON THE BULL GEAR AND BOTH SECOND STAGE PINIONS WERE SPALLED AND MISSING MATERIAL. THE WEAR PATTERNS OF THE GEARS SHOWED HEAVY WEAR ON THE FRONT HALVES AND THE SPALLED SECTIONS WERE ALL IN THE FRONT HALF OF THE GEAR TEETH. NO ALIGNMENT ERRORS WERE FOUND NOR LUBRICATION OR RESIDUAL MAGNETISM SEEMED TO BE AT FAULT. THE NR 11 BEARINGS WERE FOUND TO HAVE MISMATCHED SERIAL NUMBERS. SEVEN RGB''S TO DATE WITH SIMILAR PROBLEMS HAVE BEEN REPORTED BY THE SUBMITTOR AND THE OPI IS AWARE AND REVIEWING THE SERVICE DIFICULTIES EXPERIENCED.