Colisión en el aire entre ASW 20L y DG-500 cerca de Walliser Wispile, Suiza

El 29 de julio de 2003, un Alexander Schleicher ASW 20L y un DG Flugzeugbau DG-500/22 ELAN colisionaron en el aire cerca de Walliser Wispile, Suiza. Ambos planeadores estaban realizando un vuelo de ascenso alpino durante un campamento de entrenamiento. La colisión ocurrió a aproximadamente 2700 metros de altitud, resultando en la destrucción de ambos planeadores. Dos pilotos sobrevivieron al saltar en paracaídas, mientras que el tercer piloto lamentablemente murió en el incidente. La investigación oficial determinó que la colisión fue causada porque los pilotos se vieron demasiado tarde.

1. Cruise alpine soaring: Both gliders were in straight-and-level alpine soaring flight around 2700 m MSL in the Walliser Wispile area after departing from Zweisimmen (DG-500) and Saanen (ASW 20L).
2. Multiple gliders nearby: The ASW 20L pilot was aware that at least four other gliders were operating in the same area, increasing traffic complexity without any specific separation or coordination.
3. Inadequate lookout: Despite both DG-500 pilots sharing lookout duties and the ASW 20L pilot scanning the area, neither crew detected the opposing glider in time to avoid conflict.
4. Opposing traffic sighted late: While cruising on reciprocal tracks, the ASW 20L pilot suddenly saw the red nose of the DG-500 very close ahead and the DG-500 rear-seat pilot heard a shout and then saw the other glider on collision course.
5. Last-moment evasive inputs: Both pilots attempted to evade— the ASW 20L pilot pulled the stick left and the DG-500 front-seat pilot likely banked left and pushed to pass underneath— but with insufficient time and separation.
6. Frontal mid-air impact: The two gliders collided nearly head-on, causing major structural damage including separation and severe damage to wings and cockpits.
7. Crash - fatal: Both gliders were destroyed, the ASW 20L pilot and DG-500 rear-seat pilot bailed out and survived with broken feet, and the DG-500 front-seat pilot was unable to escape and was fatally injured in the subsequent crash.