Service difficulty report · Disk

Difficulty date
August 3, 2010
Submitted
August 13, 2010
Operation
General aviation
Engine
Pwa JT8D219
Part
Disk
Part number
777603
Part serial
T23324
Condition
Cracked
Location
Engine
Part time
35,654 hours
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

DURING DISASSEMBLY OF THE TURBINE MODULE IT WAS NOTICED THAT THE DISK (PN 777603) WAS CRACKED AT THE FIR TREE. ALSO NOTED, WERE (2) CRACKED BLADES (PN 798403), BOTH LOCATED NEAR (WITHIN (1) FIR TREE) OF THE DISC CRACK. THIS IS A KNOWN PROBLEM AND HAS BEEN PREVIOUSLY REPORTED SOME YEARS AGO. HOWEVER, IN THIS INSTANCE THE CRACK HAS OCCURRED IN THE SECOND FIR TREE RATHER THAN THE FIRST (MOVING FROM OUTSIDE INWARDS). MFG AND CUSTOMER HAVE BEEN ADVISED. STILL AWAITING FURTHER ADVICE FROM MFG.