What happened
On July 13, 2001, at approximately 16:00, a Rolladen Schneider LS 7 glider, registration PH-9HD, was engaged in a local flight near Guillestre, France. The pilot, who was participating in a flight training course at the Saint-Crépin aero club, had initially flown toward Col Agnel and Mont Viso. While operating at an altitude of 3,000 meters on the western slopes of Mont Viso, the pilot attempted to utilize thermal lift but was unable to do so due to highly turbulent atmospheric conditions.
Seeking to return to the airfield as quickly as possible, the pilot elected to fly a direct course back to the aerodrome. During the transit of north-south oriented ridges, the glider encountered severe downdrafts. While crossing a ridge near "Sommet Bucher," the aircraft struck the tops of trees. The impact caused the glider to fall approximately 200 meters, landing upside down. The aircraft sustained significant damage to the right wing and the cockpit area.
The investigation
The investigation examined the pilot's flight planning, the meteorological conditions, and the sequence of maneuvers leading to the impact. Investigators reviewed the Saint-Auban meteorological bulletin, which indicated a fast westerly flow with winds reaching approximately 30 knots at 3,000 meters. The pilot had attended the morning weather and pilot briefings prior to the flight. The investigation also assessed the pilot's experience, noting they had accumulated 400 total flight hours, with 32 hours flown in the preceding six months.
Findings
- The primary cause of the accident was the insufficient consideration of meteorological conditions during the return leg of the flight.
- The pilot was influenced by stress and a desire to reach the departure airfield quickly, which led to the decision to fly a direct route through terrain without properly accounting for the severe downdrafts and turbulence present.
- The atmospheric conditions were characterized by high turbulence and strong westerly winds at altitude.