# SDR SWAA2021102725516

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 3, 2021
- Submitted: October 27, 2021
- Operation: Air carrier
- Aircraft: [N232WN](https://openairdocs.org/aircraft/N232WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 32500
- Aircraft time: 53,002 hours, 31,465 cycles
- System (JASC): [5310 · Fuselage Main, Structure](https://openairdocs.org/jasc/5310)
- Part: None
- Condition: Corroded
- Location: Fuselage
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SWAA2021102725516

## Discrepancy

CORROSION ON SUBTHRESHOLD WEB AT FWD CARGO BAY BS 454 - 476, RBL 28, WL 156.  EVALUATED DAMAGE ON SUBTHRESHOLD WEB. ORIGINAL THICKNESS .045' DAMAGE REMOVED; .009' REMAINING THICKNESS .0036 L= 2' X W=1.2' DEPTH .009 DAMAGE EXCEED 10% OF ORIGINAL THICKNESS, FOUND TO BE OUT LIMITS IAW SRM 53-30-15-1A-1; 4.G.(12).  REMOVED SUBTHRESHOLD WEB IAW SRM 51-40-02.   LOCATED, DRILLED AND COUNTERSINK  NEW SUBTHRESHOLD WEB IAW SRM 51-40-05-0G-0, SRM 51-40-08-0G-0 & DWG 143A8330.  INSTALLED FCB SUBTHRESHOLD WEB IAW SRM 51-40-02-0G-0 PAR. 5 AND DWG 143A8330.  INSTALLED FCB SUBTHRESHOLD WEB IAW SRM 51-40-02-0G-0 PAR. 5 & DWG 143A8330.

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