What happened
On June 12, 2002, a Centrair C 101 A glider, registered F-CGSO, was participating in a local flight at the Nevers aerodrome. The flight began with a standard tow operation, marking the first tow of the day. Approximately six minutes into the flight, while at an altitude of 500 meters and 2.5 nautical miles southeast of the airfield, the pilot released the tow cable.
Immediately following the release, the pilot observed a significant increase in the rate of descent, approximately five meters per second, accompanied by a rapid decrease in airspeed. The pilot notified the Nevers control tower of an intention to perform an off-field landing and identified a nearby field adjacent to an urban area. During the final approach, the pilot realized that the airbrake controls were unlocked. This caused the aircraft to stall at a low altitude, resulting in a violent impact with the ground. The aircraft was destroyed.
The investigation
The investigation focused on the flight parameters following the cable release and the configuration of the glider's flight controls. Investigators examined the pilot's actions during the emergency and the state of the aircraft's airbrakes. The investigation established that the airbrakes had been left in an unlocked position prior to takeoff. Furthermore, the investigation looked into the visibility of the aircraft's configuration to the tow plane pilot, who reported that the unlocked airbrakes were not visible during the towing process.