What happened
On June 28, 2020, a training flight involving an ASG-32 glider ended in a hard landing at the Montricher aerodrome. The flight was part of a familiarization program where a pilot, who was experienced in powered aircraft but unfamiliar with camber-changing wing profiles, was flying with an instructor. Following a successful initial flight, the second flight resulted in a significant error during the final approach.
While on final approach, the pilot mistakenly manipulated the flap controls instead of the airbrake controls. This error caused the flaps to be set to position L. Believing the approach was too high, the pilot attempted a correction maneuver without deploying the airbrakes. This lack of drag caused the aircraft's speed to increase, resulting in a high and long approach. The instructor eventually deployed the airbrakes when approximately two-thirds of the runway had been traversed. During the flare, at an altitude of roughly one meter, the aircraft dropped abruptly, causing the landing gear to collapse upon impact.
The investigation
Investigators examined the cockpit layout and the sequence of pilot actions. They noted that the flap and airbrake controls are positioned closely together on the left side of the cockpit, and the handles share a similar shape. The investigation focused on the instructor's ability to intervene and the pilot's visual verification of control positions.
Findings
- The primary cause of the accident was the pilot's confusion between the flap and airbrake controls, which was not identified by the instructor until too late.
- The pilot failed to visually confirm the position of the control lever during the maneuver.
- The instructor's late detection of the error prevented timely correction of the glide path.
- The sudden drop during the flare was likely caused by the unexpected retraction of the flaps, which may have occurred if the pilot released the lever during the flare phase.
Safety action
- A more thorough approach briefing, specifically stating the intended flap position, could have allowed the instructor to detect the control error earlier.
- Improved visual monitoring of control lever positions by the pilot could have prevented the misconfiguration.