# SDR AALA202405269953

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 9, 2024
- Submitted: May 26, 2024
- Operation: Air carrier
- Aircraft: [N534UW](https://openairdocs.org/aircraft/N534UW), registered now
- Make and model: Airbus A321-231
- Registry model: [Airbus A321-231](https://openairdocs.org/model/airbus-a321-231) (OpenAirDocs)
- Aircraft serial: 3989
- Aircraft time: 50,007 hours, 18,938 cycles
- System (JASC): [4900 · Airborne Auxiliary Power Unit (APU) System](https://openairdocs.org/jasc/4900)
- Part: Tube
- Part number: 38850101
- Condition: Coked
- Location: Apu
- Stage of operation: DE
- How discovered: O
- Nature of condition: B
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202405269953

## Discrepancy

AIRCRAFT WAS GROUNDED: FLIGHT ATTENDANT REPORTED THAT AFTER TOP OF DECENT THERE IS A BURNING CHEMICAL SMELL IN THE CABIN STRONGEST BY THE 2 DOOR. ODOR WENT AWAY THEN RETURNED ON LANDING.  MAINTENANCE REPLACED THE APU GEARBOX VENT TUBE DUE TO COKING, REPLACED THE AIR/OIL SEPERATOR CARBON SEAL (AALA202405261577) AND THE APU OIL COOLING FAN SHAFT O-RING (AALA202405267254). A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED.

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