What happened
On June 6, 2014, a Rans Coyote II ultralight, identified as 30-TG, was performing a solo navigation training flight from Nîmes Courbessac to Alès Cévennes. While cruising at approximately 2,000 feet, the pilot experienced a loss of power followed by a complete engine failure of the Rotax 582 engine.
After checking the fuel levels and attempting unsuccessful restart procedures, the pilot selected a nearby field for an emergency landing. During the descent, the pilot performed several 360-degree left-hand turns to position the aircraft. On final approach, the aircraft suffered a sudden loss of altitude and entered a stall, making the trajectory uncontrollable. The aircraft subsequently collided with a wall belonging to a karting track, resulting in the destruction of the aircraft.
The investigation
The investigation focused on the mechanical condition of the aircraft and the pilot's training background. The pilot had approximately 95 total flight hours, with only 10 hours on this specific type. The investigation noted that the pilot had limited experience with emergency landing procedures and off-aerodrome operations. Additionally, the aircraft's flaps were non-functional at the time of the flight, though the flight manual permits operation without them.
While the airframe showed no significant malfunctions, a detailed examination of the engine revealed significant maintenance and component issues. Investigators found a clogged fuel filter between the tank and the engine, as well as debris present in the bottom of both carburetor bowls. Furthermore, several components within the fuel system, ignition system, and the piston/crankshaft assembly were either worn, degraded, or did not meet the manufacturer's specifications.
Findings
- The primary cause of the accident was a stall during final approach, likely resulting from insufficient airspeed monitoring.
- Contamination within the fuel delivery system likely contributed to the initial engine failure during cruise.