What happened
On October 27, 2010, a Robin DR400-180, registration F-HCIM, departed Lyon Bron accompanied by a passenger. The pilot intended to maintain specific landing qualifications for mountain airfields, specifically for wheeled operations at Alpe d'Huez, Courchevel, and Megève. Although the pilot held valid licenses, she did not possess a ski qualification, and the aircraft was not equipped with skis.
After performing a landing and takeoff at Alpe d'Huez, the flight proceeded to Courchevel, where the runway was covered in snow. During the landing at Courchevel, the snow significantly decelerated the aircraft, causing it to stop on a slope approximately 20 meters from the upper platform. Following the landing, the aircraft was manually pushed to the platform with the assistance of bystanders.
The pilot then attempted a takeoff from the snowy surface. During the takeoff roll, the aircraft failed to reach sufficient airspeed. While the aircraft briefly left the ground at the end of the runway, it immediately sank and struck trees located 150 meters below the airfield.
The investigation
The investigation examined the aircraft's flight data and environmental conditions. GPS data revealed that the speed achieved during the takeoff roll was insufficient for a safe departure. Investigators also noted that the flaps had been left in the "landing" position throughout the entire roll, a configuration that creates significant aerodynamic drag.
Environmental analysis showed that while the wind was calm and visibility was good, the temperature was +6 °C, which had made the approximately 20 centimeters of snow heavy and sticky. The investigation also reviewed the flight crew's qualifications, noting that neither the pilot nor the passenger held mountain ratings, and that operations on snowy mountain runways specifically require a ski qualification.
Findings
- The primary cause of the accident was the pilot's decision to attempt operations on a snowy mountain runway using an aircraft not equipped with skis.
- The aircraft was in an incorrect configuration, as the flaps remained in the landing position, inducing high drag.
- The presence of heavy, wet snow contributed to the lack of acceleration.
- A lack of necessary mountain qualifications and an apparent misunderated of aircraft performance in these specific conditions contributed to the crash.