Incidente del HBV Diamant durante el campeonato suizo de vuelo a vela cerca de Trimbach
El 24 de mayo de 1972, un HBV Diamant experimentó un incidente cerca de Trimbach, Francia, durante el campeonato suizo de vuelo a vela. El piloto, que participaba en una carrera triangular de 145 km, tuvo dificultades para encontrar corrientes ascendentes y decidió realizar un aterrizaje en campo. Mientras maniobraba para aterrizar, el planeador entró en pérdida y se estrelló, resultando en heridas graves para el piloto y la destrucción de la aeronave. La investigación confirmó que el accidente fue causado por la velocidad del planeador cayendo por debajo del mínimo requerido durante el giro de aterrizaje.
- Cross-country task flight: During a competition cross-country task, the pilot flew the HBV Diamant after aerotow launch from Grenchen and was returning from the first turnpoint.
- Unable to find lift: On the return leg near Barmelweid, the pilot had difficulty finding usable updrafts and began losing height.
- Continued flight low: Hoping to find lift near Trimbach, the pilot continued south of the Dottenberg toward the southwest, progressively losing more altitude.
- Insufficient height for airfield: The remaining altitude became insufficient to reach Olten airfield, forcing the pilot to plan an outlanding on a relatively small, high-grass field near Trimbach.
- Outlanding setup: The pilot selected a grass field at Grossfeld, flew two full circles to inspect it, and extended the landing gear to commit to the outlanding.
- Stall in landing turn: While turning in a relatively steep right-hand turn onto final approach, the glider’s airspeed dropped below minimum and it abruptly stalled, possibly influenced by strong gusts.
- Crash - serious injury: The glider entered a steep dive with about 45° bank and impacted the ground roughly 15 m short of the chosen field, seriously injuring the pilot and destroying the aircraft.