# SDR ASAA2025031957457

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 19, 2025
- Submitted: April 23, 2025
- Operation: Air carrier
- Aircraft: [N457AS](https://openairdocs.org/aircraft/N457AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36355
- Aircraft time: 37,855 hours, 11,929 cycles
- System (JASC): [5320 · Fuselage Miscellaneous Structure](https://openairdocs.org/jasc/5320)
- Part: Sill Drain
- Part number: 147A8540U30
- 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/ASAA2025031957457

## Discrepancy

MOP SILL AT STA 948-956 R2 IS CORRODED. GROUNDED - YES. REMOVE DAMAGE + CHECKED LIMITS. FOUND TO BE OUT OF LIMITS IAW B737-900ER SRM 53-70-15-7A-1, SRM 53-70-15-01-1. REMOVED AND REPLACED MOP SILL IAW BAC DWG # 147A0004 REV. -. . MOP SILL ORI MAT .080, REMOVED MAT .030, REMAINING MAT .050.

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