# SDR IPXA2026041895658

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 14, 2026
- Submitted: April 22, 2026
- Operation: Air carrier
- Aircraft: [N421UP](https://openairdocs.org/aircraft/N421UP), registered now
- Make and model: Boeing 757-24APF
- Registry model: [Boeing 757-24APF](https://openairdocs.org/model/boeing-757-24apf) (OpenAirDocs)
- Aircraft serial: 25281
- Aircraft time: 35,922 hours, 23,455 cycles
- System (JASC): [5315 · Fuselage Main, Floor Beam](https://openairdocs.org/jasc/5315)
- Part: Floorbeam
- Part number: 146N5017
- 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/IPXA2026041895658

## Discrepancy

MDC FLOOR STRUCTURE AT STA 1200 AND LB 0 TO RBL 24 FLOOR BEAM WITH CORROSION.  CLEANED AREA IAW SOPM 20-30-03 AND REMOVED CORROSION AT MDC FLOOR STRUCTURE AT BS 1200 AND LB 0 TO RBL 24 FLOOR BEAM IAW SRM 53-00-51-1A-1 FIGURE 101, DETAIL III. IT WAS FOUND TO BE WITHIN ALLOWED IN LIMITS. RESTORATION OF SURFACE PROTECTION TREAT AND PRIME APPLIED IAW B757-200 SRM 51-20-01-0G-0 AND TOPCOAT APPLIED IAW B757-200 AMM 51-21-15-370-801.

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