# SDR DALA2026092805370

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 25, 2026
- Submitted: September 28, 2026
- Operation: Air carrier
- Aircraft: [N435DX](https://openairdocs.org/aircraft/N435DX), registered now
- Make and model: Airbus A330-941
- Registry model: [Airbus A330-941](https://openairdocs.org/model/airbus-a330-941) (OpenAirDocs)
- Aircraft serial: 2090
- Aircraft time: 6,801 hours, 822 cycles
- System (JASC): [4990 · APU Oil System](https://openairdocs.org/jasc/4990)
- Part: Oil Cap
- Condition: Leaking
- Location: Apu
- Stage of operation: CL
- How discovered: O
- Nature of condition: K, B
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2026092805370

## Discrepancy

ATB - DIRTY SOCK SMELL AFTER TAKEOFF. RETURNED TO BOS. CORRECTIVE ACTION: FOUND APU COMPARTMENT CONTAMINATED WITH OIL FROM LEAKING OIL CAP. REPLACED OIL CAP PACKING. PERFORMED LEVEL B ECS DECONTAMINATION. RAN ENGINES AT IDLE AND APU WITH BOTH PACKS. NO SMELLS NOTED. HIGHEST P-TRAK VALUE ONLY AT 5K. REPLACED RECIRC FILTERS. HIGH POWER RUN GOOD. (9518658) AIRCRAFT WAS GROUNDED.

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