What happened
On 7 October 2019, a Pro.Mecc. Sparviero SP10 100R microlight, registered 57AYE, was engaged in a private cross-country flight. After meeting other pilots at Saint-André-de-l’Eure, the pilot and one passenger departed for Mureaux. During the return leg of the flight, the aircraft entered a steep dive and collided with a field in the commune of Jumeauville. The impact resulted in two fatalities, as both the pilot and the passenger were killed.
The investigation
The BEA examined the wreckage, the flight history, and the physical condition of the aircraft and its occupants. The investigation focused on the aircraft's weight and balance, the engine's performance, and the state of the emergency equipment. Investigators found that the aircraft's flight control linkages were intact prior to impact. While the reserve parachute was found deployed, the presence of the safety pin indicated it had only deployed upon impact with the ground.
An examination of the engine revealed a fly lodged in the main jet of one of the carburetors, which could have caused a reduction in power through carburetor desynchronization. Furthermore, the investigation analyzed the aircraft's loading, noting that the weight of the two occupants, combined with the fuel, placed the aircraft significantly above its maximum permissible take-off weight.
Findings
Several critical factors contributed to the accident:
- The aircraft was operating in an excessive weight and aft center of gravity condition. The weight without fuel was estimated at 504 kg, and with fuel, it could have reached 569 kg, both of which exceeded the maximum takeoff weight of 472.5 kg. The center of gravity was also outside the manufacturer's specified limits, leading to longitudinal instability and heightened control sensitivity.
- The increased weight likely raised the stall speed of the aircraft.
- A reduction in engine power, potentially caused by the blockage of a carburetor jet by an insect, may have led to a loss of airspeed that was not detected in time.
- The pilot's failure to remove the reserve parachute safety pin prevented the parachute from being used effectively during the descent.