Accident to the Guimbal Cabri G2 registered F-HRCR on 31/01/2019 at Pierrevert (Alpes-de-Haute-Provence)

The pilot, accompanied by a passenger, took off at about 11:30 from Aix-Les-Milles aerodrome (Bouches-du-Rhône), bound for a helipad, located on a golf course in Pierrevert (Alpes-de-Haute-Provence). After passing south of his destination, he flew east before heading towards the helipad. He did not overfly the helipad but made a wide right turn to land facing the northwest. On final, at a height of about 30 m, the helicopter suddenly began yawing to the left. The helicopter rotated several times losing height, then hit the ground and rolled over.

While approaching from the west, it is likely that the pilot saw the helipad and headed southward so that he could fly back towards the helipad in a west facing direction. Having already landed on this helipad, it is probable that he wanted to directly assess the factors required to make a decision about landing (air safety, ground safety, power, wind, approach path, etc.) while making a 360° turn, and then line up for final. This practice restricted his ability to evaluate the strength and direction of the wind and his choice of existing approach paths. On final, he did not modify his flight path to avoid flying over tall trees even though the environment allowed him to do so. At this point, he was flying at a low airspeed, out-of-ground effect, with a crosswind from the right with a tailwind component. These conditions were conducive to an uncontrolled departure in yaw.

The pilot was not at ease with the Cabri G2 and more accustomed to flying helicopters with a main rotor which rotates anti-clockwise. He was probably surprised and destabilized by the departure in left yaw and probably did not counter it with sufficient speed or right pedal input. This rotational movement may then have been exacerbated either by an inappropriate reflex action by the pilot on the collective lever or pedal, or by a combination of both. The pilot was unable to stop the rotation and then lost yaw control of the helicopter, which hit the ground and rolled over.

The loss of yaw control was the result of the pilot not taking sufficient account of the wind on final and late or inappropriate action to counter it. The choice of flight path whereby the helicopter flew out-of-ground effect contributed to placing the helicopter in a position from which it was difficult to recover.