What happened
On 19 May 2023, a Robin DR400-140B, registration F-GGJS, was performing a local flight at Cosne-sur-Loire aerodrome with an instructor, a pilot, and one passenger on board. During the approach to runway 11, the instructor took control of the aircraft to demonstrate a specific crosswind landing technique involving banking into the wind to correct drift.
As the aircraft entered the flare, it gained unexpected altitude due to an abrupt change in pitch. Attempting to reject the landing, the instructor applied full power; however, the aircraft failed to accelerate. The aircraft remained on the backside of the power curve, likely due to the combination of high pitch attitude, landing flaps, and the engine's carburettor heat being engaged. This led to a stall at a very low altitude. The aircraft touched down on the right side of the runway, veered off the paved surface, and eventually struck a metal fence located near a work zone, resulting in substantial damage to the aircraft.
The investigation
The BEA examined GNSS position recordings, aircraft wreckage, and statements from the crew. The investigation focused on the flight path, which showed a significantly steeper approach slope than the standard 3 degrees, reaching up to 6.3 degrees. Investigators also analyzed the aircraft's configuration, noting that the flaps were in the landing position and the carburettor heat control was pulled. The investigation also considered the instructor's recent experience with this specific model and the use of a non-standard drift correction technique.