Mosquito B launch incident at Gruyère Aérodrome resulting in severe damage
On August 2, 1985, a Glasflügel Mosquito B experienced a launch incident at Gruyère Aérodrome in Switzerland. During the winch launch, the glider entered a steep climb shortly after takeoff. The winch operator released the cable, but the pilot was unable to prevent a hard landing. The pilot sustained serious injuries, and the aircraft was destroyed. The investigation concluded that the accident was likely due to the seat back not being properly secured, causing the pilot to lose control.
- 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.