What happened
On August 12, 2018, an Alexander Schleicher ASH25M self-launching glider, registration D-KXDD, departed from Serre-la-Bâtie Montsaléon aerodrome for a private flight. The pilot, accompanied by a passenger, was engaged in slope soaring along the Roche Rousse massif. During the flight, the pilot maintained radio contact with another glider pilot, following a path that included performing figures of eight to exploit the terrain's lift.
At approximately 13:00, while flying near the southern slope of the massif, the glider entered a sharp left turn toward the terrain. Witnesses on the ground observed the aircraft suddenly adopt a nose-down attitude before impacting the mountainside approximately 100 meters below the ridge. The impact resulted in two fatalities and the total destruction of the aircraft.
The investigation
The BEA analyzed data from the aircraft's LX9000 and LX9000D GNSS computers, which recorded the flight path and cockpit noise levels. The investigation established that the engine was shut down for the duration of the flight's end. Analysis of the wreckage and the impact site revealed that the aircraft struck the ground at high speed with a significant nose-down attitude and a right bank of at least 45 degrees.
Investigators also examined meteorological conditions, noting well-established thermals and moderate to strong local turbulence. The investigation found no mechanical malfunctions in the glider and determined that the pilot's medical condition was not a contributing factor.