What happened
On April 1, 2002, at 16:45, a Grob G103 Twin 3 ACRO glider, registration F-CGXF, was performing a winch launch for instruction purposes at the Cambrai Niergnies aerodrome. During the takeoff roll on the unpaved runway 26, the crew noted that the cable parachute briefly opened and then closed. As the glider reached a distance of 150 meters, the instructor called out a speed of 100 km/h, at which point the student pilot initiated a rotation. This resulted in an excessive pitch angle of approximately 45 degrees.
At an altitude of roughly 40 meters, the crew noted a loss of acceleration. Simultaneously, the cable parachute opened and failed to close, as the release mechanism had triggered. The instructor took control of the aircraft and attempted to manage the flight by deploying and immediately retracting the airbrakes. However, due to the low airspeed and insufficient altitude, the crew was unable to execute a proper flare. The glider struck the runway nose-first with significant force, causing the fuselage to break at the tail section. The aircraft came to a stop a short distance from the impact point.
The investigation
The investigation focused on the mechanical state of the winch release system and the flight maneuvers performed by the crew. Investigators found no malfunctions in the cable locking system or the mobile winch mechanism. It was noted that the student pilot had informed the instructor of his limited experience with winch launches prior to the flight.
Data from the previous day indicated that another instructor had experienced similar intermittent parachute openings due to a tailwind component; however, that flight was managed using a much shallower pitch angle of 15 degrees, in accordance with the club's standard procedures.