# SDR UPS405416

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 2, 1996
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: [N691UP](https://openairdocs.org/aircraft/N691UP), registered now
- Make and model: Boeing 747121
- Aircraft serial: 19641
- System (JASC): [5320 · Fuselage Miscellaneous Structure](https://openairdocs.org/jasc/5320)
- Part: Stiffener
- Condition: Cracked
- Location: Bs 1800
- Stage of operation: IN
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UPS405416

## Discrepancy

WHILE IN FOR C-CHECK, MAINTENANCE FOUND CRACK IN UPPER STIFFENER AND DEFORMATION ON LOWER STIFFENER OF FRAME AT BS 1800 LBL 14, AFT CARGO COMPARTMENT.  REPLACED STIFFENERS PER SRM 51-30-02.

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