# SDR SWAA2020100516972

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 17, 2020
- Submitted: October 5, 2020
- Operation: Air carrier
- Aircraft: [N499WN](https://openairdocs.org/aircraft/N499WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 32481
- Aircraft time: 54,217 hours, 32,098 cycles
- System (JASC): [5330 · Fuselage Main, Plate/Skin](https://openairdocs.org/jasc/5330)
- Part: Skin
- Condition: Corroded
- Location: Bs 992-996
- 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/SWAA2020100516972

## Discrepancy

CORROSION UPON REMOVAL OF AFT DRAIN MAST, FOUND EXTERNAL SKIN CORROSION.  BS 992 TO BS 996 BETWEEN S-24L AND S-25L LBL 25.  REPAIR ACCOMPLISHED, PER ATS ER NR 20-03297 REV IR & EA NR 20-153-01791 REV IR DATED 29-SEP.2020.

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