# SDR QR9R2025051600001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 16, 2025
- Submitted: May 16, 2025
- Operation: General aviation
- Filed by: [M1 Support Services, repair station QR9R369D](https://openairdocs.org/faa-repair-station/QR9R369D/m1-support-services.md) (OpenAirDocs)
- Make and model: Bolkms BK117C2
- Aircraft serial: 9176
- Aircraft time: 3,956 hours
- System (JASC): [6240 · Main Rotor Indicating System](https://openairdocs.org/jasc/6240)
- Part: Sensor
- Part number: 430106202
- Condition: Faulty
- Location: Rotor Speed
- Stage of operation: CR
- How discovered: V
- Nature of condition: F
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/QR9R2025051600001

## Discrepancy

FAULTY TRIPLE TACHOMETER NR INDICATION WITH TWIST GRIPS IN FLIGHT (INTERMITTENT 101 TO 0 INDICATIONS WITH W/U DISPLAY AND AUDIO). REMOVED AND REPLACED NR SENSOR IAW AMM 62-41-00, 41. MOC OK.

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