Accident Overview
On 12 June 2021 at 11:39 local time, a Eurocopter EC120B helicopter (registration HB-ZCA) operated by Heli-Lausanne SA departed from Lausanne-La Blécherette aerodrome (LSGL) with five persons on board, including two children, for a pleasure flight towards Montreux and the Dents du Midi. The flight returned to the same airport.
Accident Sequence
Upon return, the helicopter approached for runway 18 and after a stabilized approach, the pilot initiated a left turn out of ground effect to reach the departure hangar tarmac. During this turn, the pilot was unable to stop the maneuver, and the helicopter performed several uncontrolled left rotations about the yaw axis before making a hard landing on the grass at the edge of the runway.
Aircraft and Damage
The helicopter came to rest in the grass with the right landing gear collapsed. The transversal structure of the landing gear was severely deformed on the right side, causing a significant tilt but without allowing the main rotor blades to contact the ground. No other visible damage was reported, and the pilot stated that the aircraft had no pre-existing defects.
Analysis and Conclusions
According to the investigation, the loss of yaw control resulted from inappropriate pedal input at the moment of stopping the turn, relative to the power demanded. The pilot's eventual reduction of power by lowering the collective prevented more serious damage. The manufacturer had issued an information notice (IN 3539-I-003) for this helicopter model equipped with a Fenestron tail rotor, noting that larger pedal displacements are required compared to a conventional tail rotor when transitioning from cruise to hover flight.
The accident was attributed to a loss of yaw control near the ground.