# SDR QML2011102000003

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 20, 2011
- Submitted: November 4, 2011
- Operation: Air carrier
- Aircraft: [N407SL](https://openairdocs.org/aircraft/N407SL), registered now
- Make and model: Bell 407
- Registry model: [Bell 407](https://openairdocs.org/model/bell-helicopter-textron-canada-407) (OpenAirDocs)
- Aircraft serial: 53564
- System (JASC): [5302 · Rotorcraft Tail Boom](https://openairdocs.org/jasc/5302)
- Part: Frame
- Part number: 206032308121
- Condition: Cracked
- Location: Tailboom
- 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/QML2011102000003

## Discrepancy

DURING INSP OF THE TAILBOOM AND ATTACH POINT, CRACKING WAS NOTED IN THE UPPER STARBOARD ATTACH BOLT HOLE OF THE TAILBOOM ATTACH FRAME.  PN 206-032-308-121, LOCATED AT STA 231.472.  AXIAL STRESS EXERTED AT THIS LOCATION BY TAILBOOM FLEX, OVERTIME, CAUSES WEAKENING AND CRACKING IN THE FRAME.  INSTALLATION OF A STIFFENER/DOUBLER IN THE AFFECTED LOCATION MAY PREVENT RECURRENCE.

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