What happened
On August 11, 2006, at approximately 15:10 UTC, two gliders collided in mid-air near Curienne, France. The first aircraft, a Rolladen Schneider LS8A with registration F-CGZO, had been conducting a circuit flight since 12:38 UTC. The second aircraft, a Centrair C101 with registration F-CHLP, had departed via winch launch at 14:36 UTC for a solo ridge soaring flight.
Both aircraft were performing ridge soaring along the western flank of Mont Saint Michel. The F-CGZO was flying on a southbound route, while the F-CHHD was following a northbound route. The two aircraft were flying on converging trajectories at a low altitude. At an altitude of approximately 800 to 900 meters, the gliders struck each other head-on. Following the impact, the F-CHLP crashed into a forested area near a road, while the F-CGZO entered a dive and struck the ground roughly 100 meters from the first wreckage.
The investigation
The investigation focused on the flight paths, environmental conditions, and the visibility of the aircraft. Investigators utilized GPS data from the F-CGZO to reconstruct the flight trajectories, which confirmed the converging paths of the two gliders. The investigation also examined the visibility conditions, noting that both aircraft were predominantly white and flying against a backdrop of 7/8th cumulus clouds at 1,800 meters.
Investigators also reviewed the aircraft equipment, noting that neither glider was equipped with a proximity warning system (FLARM). The study of the wreckage revealed that the pilot of the F-CGZO had attempted an in-flight bailout; the canopy was broken, and the pilot's parachute was partially deployed, though the canopy release had not been activated before impact. The pilot of the F-CHLP was found trapped in the cockpit due to the aircraft overturning upon impact.