What happened
On 22 July 2019, at approximately 14:15, a Lange Aviation Antares 20E glider, registration HB-2417, struck a mountain ridge near La Javie in the Alpes-de-Haute-Provence region. The pilot had departed from Vinon aerodrome earlier that day for a private cross-country flight. After navigating the Durance valley and utilizing thermal uplifts, the pilot began performing spiral maneuvers above the Blayeul mountain ridge.
During these maneuvers, the pilot realized the aircraft was too close to the terrain and was unable to execute a turn to clear the ridge. The aircraft struck the terrain at an altitude of approximately 1,947 meters. The pilot sustained slight injuries, but the glider was destroyed.
The investigation
The investigation utilized data from an "iGlide Lite" application running on an iPod, which was connected to the aircraft's FLARM system. This data allowed investigators to reconstruct the flight path, revealing that the aircraft was at an altitude of roughly 70 meters above the ridge at the final recorded point before impact.
Investigators examined the meteorological conditions, which included moderate to strong turbulence and a cloud base of 3,600 meters. The wreckage was located on the eastern side of the Blayeul ridge, and the engine pylon was found in the retracted position. The pilot, an experienced flyer with approximately 4,000 flight hours, noted that the day's thermal conditions were unfavorable, requiring the use of the electric motor on three separate occasions during the flight.
Findings
Analysis of the flight sequence indicates that the pilot was performing spirals in thermals in close proximity to the terrain while maintaining a low airspeed. It is believed that the pilot likely entered the lee side of the terrain, causing a sudden loss of altitude. Because the aircraft was already below the ridge height and traveling at a low speed, the pilot lacked the necessary energy and altitude to complete a safe turn away from the obstacle.