# SDR SWAA2023050826635

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 12, 2023
- Submitted: May 8, 2023
- Operation: Air carrier
- Aircraft: [N7747C](https://openairdocs.org/aircraft/N7747C), registered now
- Make and model: Boeing 737-7BD
- Registry model: [Boeing 737-7BD](https://openairdocs.org/model/boeing-737-7bd) (OpenAirDocs)
- Aircraft serial: 36091
- Aircraft time: 50,467 hours, 25,711 cycles
- System (JASC): [5510 · Horizontal Stabilizer Structure](https://openairdocs.org/jasc/5510)
- Part: Stiffener
- Condition: Cracked
- Location: Zn 300 Stabilize
- 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/SWAA2023050826635

## Discrepancy

AS PER CUSTOMER REQUEST - ACCOMPLISH NDT VERIFICATION FOR CRACK AT R/H HORIZONTAL STABILIZER RIB #4; STIFFENER #4 & FWD AND AFT; UPPER AND LOWER CHORDS.<[01] CRACK CONFIRMED AT LOWER SECTION OF STIFFENER #4 OF RIB #4 IAW NDTM PART 6; 51-00-00 PROCEDURE 23. CRACK LENGTH : 0.468'<BR>[NORTEC 600 ; B/C 172389 ; CALIB.DUE- 3/23];[02] PERFORMED HFEC ON R/H HORIZONTAL<BR>STABILIZER RIB #4 ; FWD AND AFT; UPPER AND<BR>LOWER CHORDS; IAW NDTM PART 6; 51-00-00<BR>PROCEDURE 23. NO CRACKS FOUND.;[03] VERIFIED STEPS 1 AND 2

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.