What happened
On the evening of April 21, 2007, a Chetverien 01 ultralight, identified as 71-KT, was involved in a fatal accident near Saint-Mard-de-Vaux. The aircraft, a weight-shift pendular type of amateur construction, departed from a private field in Barizey carrying the pilot and one passenger.
During the local flight, the aircraft approached the village of Saint-Mard-de-Vaux from the north at a very low altitude. While flying in a straight line over a residence belonging to a relative of the pilot, the cockpit area of the ultralight struck the ridge of the house's roof. Following the impact, the aircraft crashed approximately 70 meters away from the building. The collision resulted in one fatality and left the pilot with serious injuries. The aircraft was destroyed in the crash.
The investigation
The investigation focused on the flight path and the mechanical state of the aircraft. Witnesses on the ground observed the aircraft flying at low altitude and noted that the engine was maintaining a constant RPM during the approach to the house. Post-accident examination of the wreckage revealed no mechanical malfunctions or technical failures that contributed to the accident.
Investigators also noted that the pilot had a pattern of performing low-altitude flights over the commune, having performed a similar low-level flight over the same village earlier that afternoon. Additionally, a blood alcohol test performed on the pilot following the accident showed a concentration of 0.48 g/L.