Introduction
On 26 August 1962, a glider accident occurred near Berschis in the canton of St. Gallen, Switzerland. The aircraft, a Rhönlerche II registered as HB-666, was destroyed after colliding with the cables of a material cableway. The two occupants sustained fatal injuries.
Aircraft and Pilot
The glider was a two-seat, strutted high-wing design of mixed construction, built in 1960 by Alexander Schleicher. It had a maximum takeoff weight of 400 kg and a takeoff weight of 370 kg at the time of the accident. The pilot, born in 1931, held a glider pilot license since July 1961 with a special permit for passenger flights. He had accumulated 61 hours and 22 minutes total gliding experience, including 14 hours 25 minutes on two-seaters. He was familiar with the accident aircraft. The passenger, born in 1934, had no aviation background; he requested a flight after observing operations. The passenger's father owned a holiday home in the area.
Sequence of Events
The accident occurred during the normal Sunday flying operations of the Segelfluggruppe Churfirsten, conducted from Walenstadt airfield (430 m above sea level) due to the usual field at Mollis being occupied. Prior to the flight, the flight instructor and other pilots warned about obstacles near Berschis and advised not to fly beyond Tscherlach. The pilot had conducted two earlier flights that day. At approximately 1638 hours, the glider was towed aloft by a tug aircraft, releasing near Tscherlach at about 600 m altitude around 1645. The pilot then flew parallel to the slope, losing altitude. He flew close to the Gilbiwand slope, despite knowing of cableways in the area. At about 1650, the glider struck the cables of the Gela–Schlums material cableway at an altitude of 850 m, severing the left wing. The aircraft then crashed onto a rock ledge approximately 50 m below.
Investigation Findings
Post-accident examination revealed no technical defects in the glider. The cableway, built in 1954 and properly reported as an obstacle, consisted of two parallel cables (12 mm diameter, spaced about 140 cm apart) spanning from 470 m to 1100 m elevation. The point of impact was 40–50 m below a cable support, where the cables were 60–80 m above the ground and 60–100 m from the slope. The weather was fair with light clouds, a west wind of 5–10 knots, and moderate thermals. Visibility was 30–40 km. The sun azimuth at time of accident was 261° with an elevation of 22°.
Operational Context
The glider group had no official authorization for commercial passenger flights, but some passengers paid for rides. The pilot had been specifically warned about the cableway at Berschis by the flight instructor before departure, and the pilot acknowledged the hazard, stating he had a healthy fear of it. Nevertheless, he flew close to the slope, likely attempting to stay in weak lift.