ASW-15 outlanding in challenging terrain near Rüschegg-Graben, Switzerland
On May 7, 1972, a Schempp-Hirth ASW-15 experienced an outlanding near Rüschegg-Graben, Switzerland. The pilot, participating in a regional competition, encountered difficulties returning to Bern due to disorientation and a reported variometer failure. The pilot chose to land in a small field surrounded by obstacles, resulting in a hard landing that damaged the aircraft's fuselage and tail. Despite the heavy damage to the ASW-15, the pilot was unharmed, and no third-party damage occurred.
- Cross-country return leg: During the return leg of a Bern–Romont–Bern task, the pilot was flying cross-country in weak thermals under 4–6/8 cumulus with bases around 1400–1700 m.
- Disoriented near Bern: On the way back the pilot had difficulty locating the Bern airfield and drifted south of the intended course toward the Schwarzenburg area.
- Weak thermals, low height: In the Schwarzenburg area the pilot was at relatively low altitude in generally weak thermal conditions, limiting his options.
- Perceived vario failure: Near the shortwave transmitter at Schwarzenburg the pilot reported a temporary failure of the electric variometer, which he believed hindered his ability to exploit the weak lift, although a mechanical variometer remained available.
- Chooses small field: Recognizing his low height, the pilot decided to outland in a small 160 m field that was preceded by trees and a telephone line and bordered by an orchard and a solid fence.
- Long landing and ground loop: Despite using a sideslip and full airbrakes, the glider touched down only about 120 m into the field, and to avoid colliding with the fence the pilot forced the left wing onto the ground and executed a ground loop, bending the fuselage and damaging the tail.
- Outlanding - damage: The glider sustained severe structural damage in the off-field landing and ground loop, while the pilot remained uninjured and no third-party damage occurred.