What happened
On September 18, 2013, at approximately 13:40, a Schneider LS3 glider, registration PH-879, was conducting a local flight near the Vinon-sur-Verdon aerodrome. The pilot had departed via aero-tow earlier that day at 12:40.
An eyewitness, a local mechanic, observed the aircraft at an altitude of approximately 250 meters, north/northeast of the airfield. The observer noted the glider performing a right-hand turn before entering an autorotation. The aircraft completed two rotations in a tight, helical trajectory before descending at a steep nose-down attitude and disappearing behind an obstacle, where it impacted the ground.
The investigation
Investigators utilized data from a FLARM calculator installed on the aircraft to reconstruct the flight path. Technical examinations of the wreckage revealed no mechanical failures that could have contributed to the accident. The investigation confirmed that the airbrakes, flaps, and landing gear were all retracted at the time of impact, and the canopy had not been jettisoned. The wreckage showed the aircraft struck the ground with a high nose-down pitch and a rotational movement.
Medical examinations of the pilot, a 73-year-old experienced flyer with approximately 1,000 total flight hours, found no physiological factors that could explain the accident. At the time of the flight, weather conditions were characterized by 12-knot winds, visibility exceeding 10 km, and significant turbulence.
Findings
- The aircraft was properly balanced, with a 4 kg weight placed in the nose to meet manufacturer center-of-gravity recommendations.
- The pilot had attended the morning weather briefing and was flying in conditions deemed good by other pilots at the aerodrome.
- The investigation could not determine the specific cause of the initial onset of the autorotation or why the pilot was unable to recover the aircraft.