# SDR QR9R2026082100001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 21, 2026
- Submitted: August 21, 2026
- 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: 9821
- Aircraft time: 3,973 hours
- System (JASC): [7714 · Engine RPM Indicating System](https://openairdocs.org/jasc/7714)
- Part: Sensor
- Part number: 430106202
- Part serial: 181617332326
- Condition: Failed
- Location: Rotor Tach
- 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/QR9R2026082100001

## Discrepancy

IN FLIGHT NR NEEDLE ON TRIPLE TAC FAILED. IN FLIGHT NR FLUCTUATED CONTINUOUSLY BETWEEN NORMAL RANGE AND 0 WITH ASSOCIATED LIGHT AND WARNING TONES. REMOVED AND REPLACED SPEED PICK-UP SENSOR IAW AMM 62-41-00, 4-1. MOC SUCCESSFULLY COMPLETED.

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