What happened
On May 7, 1972, a Standard Libelle glider, registration HB-950, departed from Bern as part of a regional gliding competition. The pilot intended to fly a circuit via Romont before returning to Bern. During the return leg, approximately 10 km from the destination, the aircraft encountered unexpected and powerful downdertrafts.
To mitigate the impact of the weather, the pilot attempted an outlanding in hilly terrain. To shorten the landing distance, the pilot approached a grassy field with the landing gear retracted. During the landing sequence, the glider crossed a field path that was recessed approximately 60 cm into the ground. The aircraft struck the elevated edge of the path on the opposite side, causing the fuselage to break behind the wing root. The uncontrolled aircraft then bounced approximately 15 meters before coming to rest in a turnip field. The pilot escaped the crash uninjured.
The investigation
Investigators examined the pilot's credentials and the aircraft's maintenance history. The pilot was a highly experienced glider pilot with 2,598 total flight hours, including significant time on this specific aircraft model. There was no evidence of medical impairment at the time of the accident. The HB-950 was confirmed to be airworthy and properly registered.
The investigation also assessed the landing site, noting that the area near Schwarzenburg offered very few suitable landing options. Specifically, the investigators found that the depression created by the field path was nearly invisible from the air.