ASK 13 Absturz am Flugplatz Grenchen nach unerwartetem Ausklinken

Am 9. April 1980 startete ein Flugschüler mit einer Alexander Schleicher ASK 13 zu einem Solo-Übungsflug vom Flugplatz Grenchen. Kurz nach dem Start, in etwa 80 Metern Höhe, löste sich das Schleppseil unerwartet vom Schleppflugzeug. Das Segelflugzeug ging in eine unkontrollierbare Linkskurve über, die zu einem Absturz um 15:59 Uhr Ortszeit führte. Der Flugschüler erlitt tödliche Verletzungen, und der ASK 13 wurde zerstört. Der Vorfall wurde auf den Kontrollverlust nach dem unerwarteten Ausklinken zurückgeführt.

1. Aerotow initial climb: The student pilot departed solo in ASK-13 HB-926 on aerotow from Grenchen and climbed normally to about 80 m above ground.
2. Unexpected tow release: Shortly after passing the western end of the airfield at approximately 80 m AGL, the tow cable unexpectedly released from the tow aircraft while the glider was flying slightly low behind it.
3. Low altitude, student pilot: The cable release occurred at very low altitude with a relatively inexperienced student pilot who had previously shown anxiety in unexpected situations.
4. Left turn after release: After recognizing the situation and transmitting 'cable break' on the radio, the student initiated a left turn instead of maintaining straight-ahead flight and building speed over suitable landing terrain ahead.
5. Steepening descending turn: The left turn became progressively steeper with the glider increasingly nose-down, airspeed apparently low, and the aircraft entering an uncontrolled, high pitch-down attitude with about 300° change in heading.
6. Crash - fatal: The glider, still attached to the tow rope at its nose hook, impacted the ground in a steep nose-down attitude with slight left bank, fatally injuring the student pilot and destroying the aircraft.