Colisión del Ka-2b con cable cerca de Schafberg, Pontresina, Suiza

El 5 de agosto de 1963, un Ka-2b Rhönschwalbe colisionó con un cable de un teleférico de materiales cerca de Schafberg, Pontresina, Suiza. El incidente ocurrió poco después de que el planeador fuera liberado del remolque a aproximadamente 250-300 metros sobre el aeródromo de Samedan. El cable, parte de un teleférico utilizado para el control de avalanchas, no estaba marcado y era difícil de ver contra el fondo de la montaña. A pesar de la colisión, ambos ocupantes resultaron ilesos, aunque el planeador fue destruido y el teleférico sufrió daños menores.

1. Aerotow ridge entry: The Ka-2b launched by aerotow from Samedan and was towed directly into the Val Bernina along the valley-side slopes at heights in places well below the standard 150 m minimum over the terrain.
2. No obstacle briefing: Before the flight, neither the instructor nor the student reviewed the posted local obstacle chart, so the existence and approximate position of the Pontresina–Schafberg material cableway remained unknown to them.
3. Low ridge flight height: During the tow into the valley and along the slopes, the tug and glider operated at relatively low height above the hillside, reducing vertical clearance from any unseen obstacles.
4. Tow release near Schafberg: At about 250–300 m above Samedan, near the lower Schafberg slope opposite Pontresina, the instructor released from tow to continue independent ridge soaring in what he believed was a steady 3 m/s updraft.
5. Closer ridge approach: After release, the instructor slightly reduced airspeed and flew the glider closer to the Schafberg slope, maintaining more than 50 m clearance from the ground but without awareness of any overhead cables.
6. Cable impact and spin: With the cable still unseen by the instructor and only noticed moments before by the student, the left wing struck the unmarked ropeway support cable, causing the glider to yaw and roll left and enter a spinning descent into the trees.
7. Crash - no injury: The glider fell through approximately 20 m high larch trees to the ground and was destroyed, while both occupants remained uninjured and the ropeway sustained only minor damage.