Startvorfall mit Mosquito B auf dem Flugplatz Gruyère führt zu schweren Schäden
Am 2. August 1985 ereignete sich auf dem Flugplatz Gruyère in der Schweiz ein Startvorfall mit einem Glasflügel Mosquito B. Während des Windenstarts ging das Segelflugzeug kurz nach dem Abheben in einen steilen Steigflug über. Der Windenfahrer löste das Seil, aber der Pilot konnte eine harte Landung nicht verhindern. Der Pilot erlitt schwere Verletzungen, und das Flugzeug wurde zerstört. Die Untersuchung ergab, dass der Unfall wahrscheinlich darauf zurückzuführen war, dass die Rückenlehne nicht richtig gesichert war, was dazu führte, dass der Pilot die Kontrolle verlor.
- Winch launch takeoff: During a winch launch from runway 36 at Gruyères, the glider began its initial ground roll and liftoff under full power from the club-built winch.
- Seat back shifts: Shortly after liftoff, the insufficiently locked seat back likely collapsed rearwards, causing the pilot to pitch backward in the cockpit and inadvertently pull on the control stick.
- Strong acceleration: The winch provided a strong initial acceleration that was unfamiliar to the pilot at this particular airfield, contributing to his being destabilized during the launch.
- First winch at field: Although experienced in winch launches elsewhere, this was the pilot’s first winch launch at Gruyères, where local launch characteristics and acceleration were new to him.
- Excessive nose-up: About 10–15 seconds after takeoff the glider adopted an excessively steep nose-up attitude, then also rolled right, prompting the winch operator to release the cable.
- Pilot regains attitude: After cable release the pilot managed to level the glider from its nose-down trajectory but was unable to sufficiently reduce the high rate of descent.
- Crash - serious injury: The glider impacted the ground nearly horizontally with a high vertical speed, seriously injuring the pilot and destroying the aircraft.