SDR AALA202209013417

Service difficulty report · None · Boeing 777

Difficulty date: August 31, 2022
Submitted: September 1, 2022
Operation: Air carrier
Aircraft: N779AN
Make and model: Boeing 777
Aircraft serial: 29955
Aircraft time: 91,759 hours, 11,213 cycles
System (JASC): 4990 · APU Oil System
Part: None
Condition: None
Stage of operation: DE
How discovered: O
Nature of condition: B
Precautionary procedure: K

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

What was found

AIRCRAFT WAS GROUNDED: PILOT REPORTS OF ODOR ON DESCENT OF A MUSTY ODOR. DURING TROUBLESHOOTING, IT WAS DISCOVERED THAT APU WAS LEAKING OIL. REMOVED AND REPLACED APU. REFERENCE JOB CARD 72L00021001, BOTH LEFT AND RIGHT AIR CONDITIONING PACK SYSTEM COMPONENTS MUST BE REPLACED IF APU IS REPLACED DUE TO A SMOKE ODOR FUMES EVENT. **SUPPLEMENTAL REPORT WILL BE SUBMITTED**(OPEN).