# SDR QR9R20210819001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 19, 2021
- Submitted: August 19, 2021
- 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: 9430
- Aircraft time: 2,519 hours
- System (JASC): [6320 · Main Rotor Gearbox](https://openairdocs.org/jasc/6320)
- Part: Gear
- Part number: B632K1001051
- Part serial: KA1019
- Condition: Corroded
- Location: Main Rotor
- Part time: 2,519 hours
- 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/QR9R20210819001

## Discrepancy

DURING WATER INTRUSION INSPECTION, MAINTENANCE DETECTED SEVERE INTERNAL CORROSION ON TRANSMISSION GEARS DUE TO LACK OF VENTILATION.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.