What happened
On the afternoon of March 4, 2002, a Schleicher ASW 19 glider, registered F-CERT, was participating in a local flight involving a group of eighteen gliders over the Canjuers plateau. Around 13:00, the aircraft was operating in an area with active thermals, as evidenced by the presence of several other gliders in the vicinity.
Witnesses flying nearby observed the aircraft entering a rapid spiral dive. One pilot, positioned approximately 500 meters away at an altitude of 1,300 meters, reported seeing the glider rotating sharply to the left and descending vertically. The aircraft completed several rapid rotations before impacting the terrain at an altitude of approximately 1,050 meters. No radio distress calls were transmitted by the pilot prior to the impact, and there was no attempt to evacuate the aircraft.
The investigation
The investigation focused on the flight path and the aerodynamic behavior of the aircraft leading up to the collision. Investigators noted that the weather conditions at the time of the accident involved winds from 130 degrees at 15 knots with gusts up to 30 knots, with good visibility (CAVOK) and a temperature of 9 °C.
Medical examinations of the pilot were conducted, but the post-mortem results provided no significant findings regarding the cause of the accident. The investigation also considered the flight experience of the pilot, who had 88 total flight hours, including 20 hours in dual instruction, and had completed 31 hours of flight time in the three months preceding the event.
Findings
The investigation established that the aircraft struck the terrain following a period of uncontrolled flight. The primary cause of the accident was insufficient control of flight parameters, specifically leading to a spiral stall. The investigation concluded that the aircraft entered a spiral stall and subsequently entered an autorotation so close to the ground that recovery was impossible before the collision with the mountain terrain.