SDR 96ZZZX4342

Service difficulty report · Lock

Difficulty date
July 11, 1996
Submitted
March 26, 2000
Operation
General aviation
Engine
Pwa JT12A8
Part
Lock
Part number
536211
Condition
Missing
Location
4th Stage Disk
Part time
1,300 hours
Stage of operation
IN
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

METAL-TO-METAL CONTACT, BIND, BLADE RUB. INVESTIGATION FINDINGS: AN INDUCTION TEST RUN COULD NOT BE ACCOMPLISHED DUE TO RUBBING CONDITION. THE ENGINE AND COMRPESSOR ASSEMBLY WERE DISASSEMBLED TO IDENTIFY CAUSE OF DISCREPANCY. INVESTIGATION REVELAED THAT P/N 536204, FOURTH STAGE COMPRESSOR BLADE, WAS FOUND LOOSE IN THE BLADE SLOT OF THE FOURTH STAGE DISK. THE BLADE HAD MOVED AFT MAKING CONTACT WITH THE INNER SEAL AREA OF THE FOURTH STAGE COMPRESSOR STATOR, P/N 542274. P/N 536211, BLADE LOCK, COULD NOT BE FOUND AND SUSPECT IT MAY HAVE FAILED AND LEFT THE ENGINE ALLOWING THE BLADE TO WORK LOOSE. NO OBVIOUS DAMAGE FROM THE LOCK WAS NOTED.