La cuerda del ASK 13 se engancha en una línea eléctrica tras soltarse en el remolcador

Un instructor y su alumno resultaron gravemente heridos cuando su ASK 13 se estrelló en un campo en Montricher al despegar; planeador gravemente dañado. Hacia los 20 m, el gancho del remolcador se abrió solo; la cuerda se soltó de él pero quedó en el morro del planeador. Al aflojar el remolque, el instructor creyó que el planeador había soltado y se ocupó de la vía férrea, sin accionar su suelte. La cuerda se enrolló en el cable de tierra y frenó bruscamente el planeador, que cayó. El gancho solo estaba parcialmente cerrado (un cable largo hacía un bucle en la palanca); se sumó la falta de preparación ante un suelte inadvertido.

1. Aerotow takeoff: During an instructional aerotow departure from Montricher runway 03, the ASK 13 with instructor and student began the initial climb after a normal ground roll.
2. Tow hook wiring loop: On the towplane, the electrical lead to the tow-hook indicator was too long and formed a loop around the tow-hook release lever, preventing full closure of the hook latch.
3. Tow rope releases: At about 20 m above ground as the combination approached the tree line, the partially latched tow hook opened and the rope detached from the towplane while remaining attached to the glider.
4. Instructor misdiagnosis: The student did not report the rope had detached from the towplane; the instructor, feeling the loss of tow, assumed it had released from the glider and focused on clearing the railway line.
5. Rope snags power cable: With the rope still attached to the glider's nose, it brushed the treetops then wrapped around the railway line's earth wire, decelerating the glider and pitching it into a field.
6. Crash - serious injury: The glider crashed into a colza field about 60 m beyond the railway line, was heavily damaged, and both the student and instructor sustained serious spinal and leg injuries.