What happened
On 12 May 2022, a Guimbal Cabri G2, registration F-HOLA, was performing a solo instructional flight at Aix-les-Milles aerodrome. After completing several runway circuits in dual instruction, the student pilot returned to the aerodrome to land on runway 14. The wind conditions had shifted to a 210° direction at approximately 5 to 10 knots, creating a significant right crosswind component.
While performing a hover taxi at a height of between two and five metres, the student pilot attempted to turn left to clear the runway at taxiway A. During this maneuver, the helicopter suddenly experienced a loss of yaw control, rotating two to three times around its vertical axis to the left. In an attempt to regain control, the student pilot lowered the collective pitch. The helicopter subsequently made contact with the ground, bounced, and landed heavily on its belly, causing substantial damage to the airframe, including the landing gear and the Fenestron structure.
The investigation
The BEA examined the wreckage and found that the landing gear and Fenestron components had sustained significant impact damage, but the flight control linkages and engine transmission systems were intact and functioning normally. The investigation focused on the aerodynamic characteristics of the Cabri G2's Fenestron tail rotor, specifically regarding tail fin stall and yaw control in crosswind conditions.
Investigators reviewed the student pilot's training records and the manufacturer's Service Letter (SL 12-001 A), which addresses yaw control during approach. The investigation also analyzed meteorological data, noting that the student pilot had not consulted the windsock or updated weather reports, leading to an insufficient assessment of the right crosswind component compared to his previous flights.