# SDR QR9R2025040800001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 8, 2025
- Submitted: April 8, 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: 9358
- Aircraft time: 4,313 hours
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Actuator
- Part number: 41800876400
- Part serial: 800046
- Condition: Failed
- Location: Autopilot
- 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/QR9R2025040800001

## Discrepancy

FLT 1: AUTOPILOT TEST FAILED. CONSISTENTLY YAW TRIM BUT JUMPED FROM AP1 TO AP2 DURING SUBSEQUENT TESTS. A TEST FLIGHT EVAL FOUND T/R SEMA ACTUATOR GRINDING AND CHATTERING WHILE PERFORMING AFCS FUNCTION CHECK. REMOVED AND REPLACED T/R SEMA IAW AMM 67-20-00, 4-14; MOC SUCCESSFULLY COMPLETED.

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