# SDR SWAA2023060143256

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 28, 2023
- Submitted: June 1, 2023
- Operation: Air carrier
- Aircraft: [N961WN](https://openairdocs.org/aircraft/N961WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 36962
- Aircraft time: 37,902 hours, 23,158 cycles
- System (JASC): [5320 · Fuselage Miscellaneous Structure](https://openairdocs.org/jasc/5320)
- Part: Threshold
- Condition: Corroded
- Location: Zn 100 Fus Lower
- 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/SWAA2023060143256

## Discrepancy

MULTIPLE AREAS OF CORROSION ON AFT CARGO BAY THRESHOLD AT RBL 21-27 BS 787+8-847 WL 156.<[01] VERIFIED APLICABILITY FOR IDENTIFICATION<BR>IAW SRM 53-60-15-01-1<BR>AND SRM 53-60-15-1A-1 FOR ALLOWABLE DAMAGE<BR><BR>REMOVED CORROSION ON AFT CARGO BAY THRESHOLD<BR>AT AFT CARGO BAY RBL 21-27 BS 787+8 IAW SRM 51-10-02<BR>EVALUATED DAMAGE MEASURES L= 2.0' X W=1.0' D=0.015' REMAINING THICKNESS 0.030' ORIGINAL. THICKNESS: 0.045'<BR>FOUND TO BE OUT OF LIMITS IAW SRM 53-60-15-1A-1 A.D. <BR>PARA:4 (G) FIG. 103 DET. A.<BR>USED TOOL: ID: ATS 2473 S/N: UNKNOWN DUE DATE: 08/2023;[02] VERIFIED STEPS 1 AND 2 (PARTIAL) AND CORRECTION ACTION ITEM 1 AND MEASUREMENT TABLE (TO BE OUT OF LIMITS).;[03] RECEIVED NEW THRESHOLD P/N 146A8123-25; LOT: 1522932-1<BR>LOCATED AND DRILLED BETWEEN AT RBL 21-27<BR>BS 787+8 BS 847 WL 156<BR>IAW SRM 51-40-05 AND DWG: 146A8340<BR>OK TO TOP COAT[11] INSTALLED ON ACB THRSEHOLD WEB<BR>AT BS 787+8 BS 847 RBL21 WL 156<BR>IAW SRM 51-40-02 AND DWG 146A8340;[12] VERIFIED CORRECTIVE ACTION 11 AND MEASUREMENT TABLE.

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