# SDR DALA2025032702267

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 23, 2025
- Submitted: March 27, 2025
- Operation: Air carrier
- Aircraft: [N535DN](https://openairdocs.org/aircraft/N535DN), registered now
- Make and model: Airbus A321-271NX
- Registry model: [Airbus A321-271NX](https://openairdocs.org/model/airbus-s-a-s-a321-271nx) (OpenAirDocs)
- Aircraft serial: 11424
- Aircraft time: 7,655 hours, 1,842 cycles
- System (JASC): [4990 · APU Oil System](https://openairdocs.org/jasc/4990)
- Part: Oil System
- Condition: Overserviced
- Location: Apu
- Stage of operation: CL
- How discovered: O
- Nature of condition: W, B
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2025032702267

## Discrepancy

SHIP 5035 -ATB- RETURNED TO BOS AND DECLARED EMERGENCY DUE TO VISIBLE SMOKE IN THE CABIN ON TAKEOFF. CORRECTIVE ACTION: PERFORMED TROUBLESHOOTING PER NO GO ODI WORKCARDS. FOUND APU OVERSERVICED. CLEANED APU COMPARTMENT AND PERFORMED ECS DUCT DECONTAMINATION. (6795318)

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