# SDR CALA2025121912257

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 17, 2025
- Submitted: December 19, 2025
- Operation: Air carrier
- Aircraft: [N77865](https://openairdocs.org/aircraft/N77865), registered now
- Make and model: Boeing 757-33N
- Registry model: [Boeing 757-33N](https://openairdocs.org/model/boeing-757-33n) (OpenAirDocs)
- Aircraft serial: 32589
- Aircraft time: 72,509 hours, 21,526 cycles
- System (JASC): [4910 · APU Cowling/Containment](https://openairdocs.org/jasc/4910)
- Part: Longeron
- Part number: 148N373010
- Condition: Corroded
- Location: Zone 100
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2025121912257

## Discrepancy

APU COMPARTMENT LT BS 1885-1890 ABOVE APU DOOR LONGERON, METALIC HONEYCOMB SKIN INNER SURFACE CORRODED.   REPAIRED AREA OF APU COMPT. LT BS 1885-1890 IAW SRM 51 -70-10-2R-0.  PERFORMED POST CURE INSPECTION IAW NTM PART 451-00-03. DISBOND - DELAMINATION FREE.  MAJOR REPAIR ACCOMPLISHED AND VERIFIED.

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