# SDR QR9R2026081800001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 18, 2026
- Submitted: August 18, 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: 9701
- Aircraft time: 4,547 hours
- System (JASC): [6240 · Main Rotor Indicating System](https://openairdocs.org/jasc/6240)
- Part: Sensor
- Part number: 430106202
- Condition: Erratic
- Location: Rotor Tach
- Stage of operation: CR
- How discovered: O
- Nature of condition: F
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/QR9R2026081800001

## Discrepancy

ROTOR RPM INDICATOR GAVE ERRATIC INDICATIONS FROM 101% TO 80% DURING FLIGHT. THE ROTOR LOW WARNING LIGHT INDICATION FLUCTUATED INTERMITTENTLY, NEVER STAYING ON. THE LOW ROTOR AUDIO NEVER SOUNDED OFF. REMOVED AND REPLACED THE SPEED PICKUP SENSOR IAW AMM 62-41-00, 4-1. MOC SUCCESSFULLY COMPLETED IAW 05-60-00, 6-1.

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