# SDR SWAA2021091548787

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 27, 2021
- Submitted: September 15, 2021
- Operation: Air carrier
- Aircraft: [N491WN](https://openairdocs.org/aircraft/N491WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 33867
- Aircraft time: 53,758 hours, 31,898 cycles
- System (JASC): [5312 · Fuselage Main, Bulkhead](https://openairdocs.org/jasc/5312)
- Part: Stiffener
- Condition: Cracked
- Location: Bs 663 Bulkhead
- 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/SWAA2021091548787

## Discrepancy

B.S. 663 LOWER COMPOSITE BULKHEAD VERTICAL SUPPORT STIFFENER IS CRACKED AT L.B.L. 26; W.L. 150; ON AFT SIDE OF BULKHEAD. ; / [01] UPDATED MEASUREMENT TABLE; [02] REMOVED CRACKED VERTICAL SUPPORT STIFFENER BS 663; LBL 26; WL 150 AFT SIDE OF BULKHEAD PER SRM 51-40-02-0G-0; [03] LOCATED AND DRILLED VERTICAL SUPPORT STIFFENER AT B.S663 LBL 26; WL 150 AFT SIDE OF BULKHEAD PER SRM 51-40-05-0G-0;DWG 111A1000. O.K TO INSTALL.; [04] VERIFIED LOCATION; DRILL UP PER SRM 51-40-05-0G-0;DWG 111A1000. OK TO INSTALL STIFFENER; [05] INSTALLED VERTICAL SUPPORT STIFFENER BS 663; LBL 26; WL 150 AFT SIDE OF BULKHEAD PER SRM 51-40-02-0G-0;DWG 111A1000.; [06] VERIFIED SUPPORT STIFFENER INSTALLATION PER SRM 51-40-02 AND DWG 111A1000; [07] COMPLETE

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