ASK 13 Schleppseil-Verwicklung führt zu Absturz in Montricher während Trainingsflug

Am 14. Juni 1992 geriet ein Schleicher ASK 13 Segelflugzeug während eines Trainingsflugs in der Nähe von Montricher, Schweiz, in eine Schleppseil-Verwicklung. Das Seil löste sich vom Schleppflugzeug und verfing sich in einem Bodenkabel, was dazu führte, dass das Segelflugzeug auf einem Feld abstürzte. Sowohl der Fluglehrer als auch der Flugschüler erlitten schwere Verletzungen. Das Segelflugzeug wurde erheblich beschädigt, aber es gab keine Todesopfer. Der Vorfall ereignete sich kurz nach dem Start, und die Wetterbedingungen waren kein beitragender Faktor.

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 on the towplane opened and the tow rope unexpectedly detached from the towplane while remaining attached to the glider.
4. Instructor misdiagnosis: The student did not report that the rope had detached from the towplane, and the instructor, feeling the loss of tow at low height, assumed the rope had released from the glider side and focused on clearing the nearby railway line rather than operating the glider’s release.
5. Rope snags power cable: With the rope still attached to the glider’s nose, it first brushed the treetops and then wrapped around the earth wire of the nearby railway power line, abruptly decelerating the glider and causing it to pitch down into a field despite the rope eventually breaking.
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.