# SDR SWAA2026090912420

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 6, 2026
- Submitted: September 10, 2026
- Operation: Air carrier
- Aircraft: [N931WN](https://openairdocs.org/aircraft/N931WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 36637
- Aircraft time: 56,214 hours, 34,452 cycles
- System (JASC): [5315 · Fuselage Main, Floor Beam](https://openairdocs.org/jasc/5315)
- Part: Floorbeam
- Condition: Corroded
- Location: Zone 200
- 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/SWAA2026090912420

## Discrepancy

CORROSION FOUND ON THE TOP AND UNDERSIDE  AFT (WET AREA) FLOOR STRUCTURE AT RBL 30, BS 986, WL 208.  EVALUATED CORROSION ON BS 986, RBL 30, WL 208 FLOORBEAM UPPER FLANGE, ORIGINAL MATERIAL THICKNESS IS 0.150" LOWEST REMAINING MATERIAL IS 0.120" DAMAGE FOUND TO BE OUT LIMITS IAW SRM 53-70-51-1A-1, ALLOWABLE DAMAGE 1, PARA 4.D(2)(A) FIGURE 103, ALLOWABLE DAMAGE 1, DETAIL E, REPAIR TO BE PERFORM AND RECORDED ON CCN TTG8Q01DKS4G.

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