Colisión de Ka 6 durante el remolque aéreo en el aeródromo de Schänis, Suiza

El 16 de mayo de 1965, en el aeródromo de Schänis en Suiza, dos planeadores Alexander Schleicher Ka 6 CR estuvieron involucrados en una colisión durante un remolque aéreo. El incidente ocurrió cuando el cable de remolque del planeador líder se rompió debido a una tensión repentina, provocando que el planeador que seguía colisionara con el líder. El ala del planeador líder resultó dañada, pero no se reportaron heridos. El evento tuvo lugar durante una exhibición aérea pública que celebraba la apertura de la Escuela de Vuelo a Vela Alpina Schänis AG.

1. Aerotow ground roll: During a public flying event at Schänis, two Ka-6 gliders were lined up in echelon for a dual aerotow behind a D-26 towplane and began the takeoff ground roll.
2. Inadequate coordination: For this uncommon dual aerotow demonstration, there was no evidence of specific briefing or instruction given to the ground helpers on coordinated signaling and rope handling.
3. Tow started too early: The wingman of the left-staggered leading glider HB-683 signaled for start, this was relayed to the tow pilot, and the towplane applied full power even though the rope segment to the rear glider HB-703 was not yet fully tensioned.
4. Tow rope snaps: As the takeoff roll continued, the still-slack rope to HB-703 suddenly came tight with a sharp jerk and the tow rope failed in its forward third.
5. Front glider releases, turns: The pilot of HB-683 immediately released his tow rope and rolled the glider onto the left wing to avoid being overrun by the towplane.
6. Ground collision: HB-683 slewed left and its tail skid struck the already lowered left wingtip of HB-703, breaking the main spar of HB-703’s left wing.
7. Hard landing - damage: The tow pilot aborted the takeoff before liftoff and both gliders remained on the ground, with HB-703 sustaining significant wing damage but no injuries to any occupants.