# SDR QR9R20201215001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 15, 2020
- Submitted: December 15, 2020
- Operation: General aviation
- Make and model: Bolkms BK117C2
- System (JASC): [6520 · Tail Rotor Gearbox](https://openairdocs.org/jasc/6520)
- Part: Screw
- Part number: 0639435004
- Condition: Sheared
- Location: T/R Gearbox
- 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/QR9R20201215001

## Discrepancy

A POSTFLIGHT INSPECTION REVEALED TWO STUD SCREWS OF THE TAIL ROTOR GEARBOX HAD SHEARED.

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