What happened
On December 5, 1979, a pilot conducted the inaugural flight of the experimental Canard 2FL glider, registration HB-3002. The flight commenced using a bungee launch from the Zaugerli/Hüsliberg alpine pasture, with a planned landing at the Schänis airfield.
Shortly after takeoff, the aircraft performed several maneuvers. While the pilot initially followed instructions to initiate turns using the rudder, a subsequent attempt to turn using ailerons triggered a significant aerodynamic reaction. The aircraft experienced a strong negative yaw moment, causing it to deviate from its intended path. This led to a sudden half-roll into an inverted position. During the maneuver, the cockpit canopy detached from the fuselage.
Following the roll, the glider entered a backward flight phase at an altitude of approximately 50 to 60 meters. The aircraft eventually entered a steep descent, and at an altitude of roughly 25 meters, the forward wing (canard) collapsed upward. The Canard 2FL struck the ground in a slightly inverted position, resulting in the death of the pilot and the total destruction of the aircraft.
The investigation
SUST investigators analyzed film footage from the scene and examined the wreckage of the HB-3002. The investigation established that the aircraft was in a pre-certification testing phase and was being operated under a provisional permit.
Investigators reviewed the flight characteristics of the unconventional design, noting that the aircraft possessed high stability issues around the vertical axis and significant negative yaw moments during aileron use. The investigation also looked into the pilot's recent medical status and the training procedures provided by the manufacturer's test pilot prior to the flight.