What happened
On the afternoon of June 27, 2003, a Rolladen Schneider LS 7 glider, registration D-6084, departed from Mont-Dauphin for a mountain soaring flight across the Alps. The flight path took the pilot over the Ecrins Massif and the Maurienne valley before proceeding through the Grésivaudan valley.
While flying near the terrain of the Taillefer massif, specifically northwest of the Bouffrier ridge at an altitude of approximately 1,950 meters, the pilot encountered a strong updraft immediately followed by a violent downdraft. Believing the aircraft was too close to the ground, the pilot applied back-pressure on the controls. This maneuver caused the glider to stall, and the aircraft struck the ground, resulting in the destruction of the aircraft and one injury to the pilot.
The investigation
The investigation focused on the sequence of events leading to the loss of control and the pilot's physiological state. Investigators reviewed the pilot's flight experience and recent flight activity. The pilot had significant experience, including 880 hours of VFR flight time and 700 hours on this specific type of glider. However, the investigation noted a high volume of flight time in the days preceding the accident, with several flights totaling over 30 hours of flying in the four days prior to the event.
Meteorological analysis confirmed that while the day was generally favorable for soaring, the pilot had encountered difficult atmospheric conditions earlier in the flight over the Maurienne region. At the time of the accident, the weather was characterized by a light northwest wind and clear visibility.
Findings
- The primary cause of the accident was pilot fatigue, which led to an erroneous assessment of the situation and an inappropriate control input.
- The pilot's reaction to the sudden downdraft—pulling back on the stick—induced a stall at an altitude insufficient to recover the aircraft.
- The pilot had flown extensively in the days immediately preceding the accident, contributing to physical exhaustion.