What happened
On June 10, 2004, at 11:50 local time, a Robinson R22 Beta helicopter, registration F-GNDE, was involved in an accident during a local flight near Lent, France. The aircraft, operated by a flying club, had originally departed from Bourg-Ceyzeriat aerodrome. Approximately one hour into the flight, the pilot decided to land in a meadow on a hillside facing south, with the intention of taking off again immediately.
During the subsequent takeoff attempt, the helicopter reached an altitude of approximately two meters when the pilot noticed a decrease in engine power. This led to a loss of control, causing the aircraft to descend and strike the ground. The helicopter slid on its right skid and then its left skid before overturning onto its left side. The aircraft sustained heavy damage.
The investigation
The investigation focused on the environmental conditions and the pilot's performance during the takeoff. At the time of the accident, the weather was characterized by CAVOK conditions with a temperature of 28 °C and winds from 190° at 8 to 18 knots.
The investigation established that the pilot did not perform a hover in ground effect during the takeoff sequence. Furthermore, the investigation examined the aircraft's weight and power availability. The calculated mass of the helicopter at the time of the accident was 605 kg, which was below the maximum takeoff mass of 621 kg (standard temperature/sea level). However, the pilot failed to account for how the high ambient temperature and altitude would impact the available engine power.