Service difficulty report · Bull Gear · Mtsbsi MU2B35

Difficulty date
February 21, 1997
Submitted
March 26, 2000
Operation
Air carrier
Make and model
Mtsbsi MU2B35
Engine
Garrtt TPE3316
Part
Bull Gear
Part number
8937394
Condition
Failed
Location
Gr Box
Stage of operation
CR
Nature of condition
X
Precautionary procedure
E

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

What was found

(CAN) DURING CRUISE, THE RIGHT HAND ENGINE SUDDENLY FEATHERED. ENGINE SECURED. INSPECTION FOUND THAT THE BULL GEAR HAD FAILED EITHER IN THE GEAR TOOTH BASE AND/OR THE WEB DISK OR THE DISK RADIUS. COULD HAVE BEEN CAUSED BY FOREIGN OBJECT ENTERING THE GEAR MESH AREA. DAMAGE TO GEAR CAUSED LOSS OF ALL TEETH ON THE HIGH SPEED PINION AND LOSS OF DRIVE FROM THE POWER GROUP TO THE PROP, AS WELL AS DESTRUCTION OF THE SCAVENGE PUMP. DAMAGE CONFINED MAINLY TO THE DIAPHRAGM ASSEMBLY AND THE GEARBOX.