# SDR AALA202609066516

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 2, 2026
- Submitted: September 7, 2026
- Operation: Air carrier
- Aircraft: [N912UY](https://openairdocs.org/aircraft/N912UY), registered now
- Make and model: Airbus A321-231
- Registry model: [Airbus A321-231](https://openairdocs.org/model/airbus-a321-231) (OpenAirDocs)
- Aircraft serial: 6264
- Aircraft time: 38,843 hours, 16,007 cycles
- System (JASC): [4990 · APU Oil System](https://openairdocs.org/jasc/4990)
- Part: Separator
- Condition: Leaking
- Location: Apu Air Oil
- Component: Apu, Hnywl, 1319A
- Component part number: 38007081
- Stage of operation: DE
- How discovered: O
- Nature of condition: K, B
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202609066516

## Discrepancy

AIRCRAFT WAS GROUNDED: DIRTY SOCK MUSTY SMELL IN FLIGHT DECK ONLY UPON STARTING DESCENT ALL THE WAY THROUGH ENGINE SHUTDOWN - MAINTENANCE FOUND THE APU GEARBOX VENT LINE HAD EVIDENCE OF COKING - MAINTENANCE REPLACED THE APU GEAR BOX AIR OIL SEPERATOR *AALA202609066516* AND THE APU VENT LINE ASSEMBLY *AALA202609063169* - A DECONTAMINATION OF THE ENVIRONMENTAL CONTROL SYSTEM WAS ACCOMPLISHED WITH NO LEAKS OR ODORS NOTED

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