What happened
On June 1, 2013, a Centrair 101 A glider, registration F-CGEQ, was performing a local flight departing from the Montaigu Saint-Georges airfield. After climbing to approximately 1,000 meters, the pilot flew south of the airfield. After 40 minutes of flight, the pilot realized they could no longer locate the airfield. Despite attempting several turns to identify known landmarks, the pilot was unable to find the aerodrome and could not gain altitude due to a lack of thermals.
As the aircraft descended to 300 meters, the pilot decided to perform an off-field landing in a nearby field. The approach was conducted over a wheat field, and the landing took place in a field of soft earth approximately 4 km from the airfield. Upon the landing wheel making contact with the soft ground, the glider experienced a sudden and violent leftward ground loop. The aircraft came to a halt within a few meters, during which time the tail boom fractured.
The investigation
The investigation examined the pilot's experience, the aircraft's equipment, and the environmental conditions. The pilot had a glider license since November 2011, with approximately 40 total flight hours, though only 10 minutes of experience on this specific type. The aircraft was not equipped with any navigation instruments other than a compass, and the pilot was not using a GNSS receiver during this flight.
Investigators analyzed the impact site, noting a straight track in the wheat field and a 3.5-meter track in the soft earth. The landing gear was found embedded in the soil. Examination of the wreckage revealed that the tail boom had failed behind the registration markings due to overload from bending and compression forces caused by the ground loop.
Findings
- The pilot's limited experience, particularly in the area south of the airfield and the recent seasonal changes in landscape colors and landmarks, likely hindered their ability to maintain spatial orientation.
- The lack of navigation equipment, such as a GNSS receiver, contributed to the inability to relocate the airfield.
- The structural failure of the tail boom was caused by the intense mechanical stresses induced by the sudden ground loop upon landing in soft terrain.