Accident to the amateur-built microlight gyroplane identified 85ALT on 06/04/2018 at Flavacourt (Oise)

The pilot took off from runway 14 of Flavacourt microlight platform for a check flight following installation of a full cockpit canopy and a modification to the tail assembly carried out by himself. As soon as the wheels left the ground, the gyroplane yawed to the right and then gained height. It turned and progressively banked to the right as it climbed. The gyroplane then suddenly rolled to the left and onto its back, fell and hit the ground approximately 300 m to the right of the threshold of runway 14.

The information obtained suggests that the gyroplane was still being further developed and modified by the pilot. It is very likely that the microlight had an aft centre of gravity that required the pilot to apply a significant nose-down input during take-offs. In addition, the yaw control of the microlight at low speed was difficult when there were power fluctuations. These handling difficulties can be explained by the inappropriate setting of the rotor head on its shaft given the relatively heavy weight of the engine and the direction of rotation of the propeller, which is the opposite of that of a propeller driven by a Rotax 912/914 engine, which is usually installed on gyroplanes.

During take-off, the pilot did not reduce power and the microlight climbed while continuing to veer right even though the pilot had applied left rudder. Under these conditions, the pilot lost control of his aircraft.