What happened
On June 7, 1998, a Mooney M 20 K aircraft, registered F-GIJC, was conducting an IFR training flight when it experienced a critical engine failure. Approximately 35 minutes after departing from Beauvais, while cruising toward Deauville at flight level 40, the pilot reported hearing a violent knocking sound originating from the engine. This was immediately followed by intense vibrations throughout the airframe.
Following the noise, the engine ceased operation, and oil was sprayed across the aircraft's windshield, obscuring visibility. After notifying air traffic control and attempting to restart the engine without success, the pilot performed a successful emergency landing in a field near L’Aubrière – Bosgouet.
The investigation
The investigation focused on the mechanical failure of the engine, a TSIO-360 GB 3. At the time of the incident, the engine had recorded 1,072 hours of operation. Technical examination of the engine components was conducted to determine the origin of the sudden loss of power and the accompanying vibrations.
Findings
Preliminary analysis of the engine components revealed that the failure was caused by a fatigue fracture of a connecting rod body. This structural failure led to the immediate destruction of the engine.