What happened
On September 11, 2013, at 13:55 local time, an Alexander Schleicher ASW17 glider, registration D-0998, was involved in an accident near Entraunes, France. The pilot had departed from Fayence airfield at approximately 12:25 for a flight heading north. During the flight, the pilot encountered unfavorable aerological conditions. Although the pilot initially hoped to utilize rising air near nearby terrain, they realized that their altitude was insufficient to safely clear the upcoming ridge and subsequently decided to turn back.
As the pilot attempted to reach a suitable field for a forced landing, the glider struck trees located before reaching the intended landing area. The impact resulted in the destruction of the aircraft.
The investigation
The investigation examined the meteorological conditions and the pilot's decision-making process. At the time of the accident, the area was experiencing a valley breeze with visibility exceeding 10 km. While cloud bases were between 2,700 m and 3,000 m, the air mass was characterized by marked convection, and cloud cover was increasing.
The pilot, who possessed significant experience including 1,850 glider flight hours and 3,000 military flight hours, had been flying regularly at Fayence. The investigation noted that the pilot had relied on weather forecasts that suggested the presence of thermals along the ridges. The pilot also identified a known landing field in Entrevaux, located at an altitude of 450 m, but this site was more than 30 kilometers away from the accident location.
Findings
- The pilot's decision to continue the flight despite encountering deteriorating aerological conditions was a primary factor.
- The pilot's excess of confidence led them to proceed with the flight under the assumption that they would find sufficient lift, despite the lack of viable landing options in the immediate vicinity.
- The flight path was maintained in an environment that did not offer safe opportunities for a field landing.