# SDR 2022FA0000524

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 8, 2022
- Submitted: September 19, 2022
- Operation: General aviation
- Aircraft: [N911TM](https://openairdocs.org/aircraft/N911TM), registered now
- Make and model: Robsin R44RAVENII
- Aircraft serial: 10194
- Aircraft time: 6,204 hours
- Engine: Lyc IO540AE1A5
- Engine time: 5,170 hours
- System (JASC): [5300 · Fuselage Structure (General)](https://openairdocs.org/jasc/5300)
- Part: Exhaust Valve
- Part number: 17B23935
- Condition: Broken
- Location: Engine
- Part time: 1,846 hours
- Component: Cylinder Assy., Lyc
- Component part number: LW12993
- Stage of operation: CR
- How discovered: B
- Nature of condition: E, R
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2022FA0000524

## Discrepancy

DURING CRUISE FLIGHT PILOT REPORTED ENGINE BEGAN TO RUN ROUGH AND MANIFOLD PRESSURE INCREASED. HELICOPTER RETURNED TO HELIPAD AND MADE A NORMAL LANDING. EXHAUST VALVE STEM BROKE AT BELL CURVE AND WAS RELEASED INTO CYLINDER.

---
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.