What happened
On the afternoon of May 26, 1997, a Glaser-Dirks DG 400 motor glider, registration F-CFVE, was operating on a private flight in the Uvernet-Fours region of France. While maneuvering over a relatively flat area in the Chanal Valley at an altitude of 2,017 meters, the aircraft entered a turn with a high bank angle. During this maneuver, the glider struck the treetop of a fir tree. The impact was severe enough to tear the right wing from the aircraft, causing the glider to disintegrate upon hitting the forest below.
Analysis of the impact sites indicated that the aircraft's trajectory was initially horizontal before the collision. The pilot, who was the owner of the aircraft, had not flown a glider in eight months prior to the accident. Due to an inability to start the engine before the flight, the pilot had been towed to altitude by another aircraft.
The investigation
Investigators examined the meteorological conditions at the accident site and the flight circumstances. At an altitude of 3,000 meters, winds were recorded from 045° at 10 to 15 knots, with visibility exceeding 10 km. However, the atmosphere was characterized by strong turbulence, broken thermals, and a temperature inversion at 2,600 meters. The investigation also noted that several other glider pilots had abandoned the site earlier that afternoon due to a lack of sufficient lift.
Findings
- The accident resulted in one fatality and the total destruction of the aircraft.
- The primary cause of the accident was the continuation of flight in unfavorable meteorological conditions.
- The pilot was performing a high-bank turn in turbulent air, which led to the contact with the trees.