# SDR SWAA2021112227918

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 7, 2021
- Submitted: November 22, 2021
- Operation: Air carrier
- Aircraft: N450WN
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 32470
- Aircraft time: 58,641 hours, 34,716 cycles
- System (JASC): [5320 · Fuselage Miscellaneous Structure](https://openairdocs.org/jasc/5320)
- Part: Web
- Condition: Corroded
- Location: Bs 799-839
- 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/SWAA2021112227918

## Discrepancy

CORROSION ON SUBTHRESHOLD WEB AT AFT CARGO BAY BS799 - BS839 RBL26 WL158. ; / [01] EVALUATED CORROSION AT ALL LOCATIONS; FOUND DEEPEST LOCATION TO BE AT BS 800 REMOVED 0.015' IN A AREA OF 1'X1' ORIGINAL THICKNESS 0.045' FOUND TO BE OUT OF LIMITS PER SRM 53-60-15-1A-1 USING ATS TOOL ID ATS1225 S/N UNKNOWN.; [02] VERIFIED CORRECTIVE ACTION STEP 1; [03] LOCATED; DRILLED; AND INSTALLED NUTPLATES ON NEW ACB SUBTHRESHOLD WEB BS794-BS847; RBL26; WL158. PER DWG 146A8340; SRM 51-40-05-0G-0; AND SRM 51-40-02-0G-0; [04] VERIFIED CORRECTIVE ACTION 3.

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