Collision du Karpf Baby lors d'un atterrissage en campagne près de Niederhelfenschwil, Suisse

Le 20 août 1965, un planeur Karpf-Flugzeugbau Karpf Baby a été impliqué dans un incident près de Niederhelfenschwil, Suisse. Le pilote a tenté un atterrissage en campagne en raison de thermiques déclinants et a choisi un champ qui n'était pas idéal. Lors de l'atterrissage, le planeur est entré en collision avec une clôture et un arbre, causant des dommages à l'appareil. Heureusement, aucune blessure n'a été signalée. L'incident souligne les défis de la sélection de sites d'atterrissage en campagne appropriés dans un terrain complexe.

1. Aerotow cross-country: The pilot departed Winterthur by aerotow for his first solo cross-country flight toward Altenrhein in marginal thermal conditions.
2. Thermals fade: Over the Nollen area the already weak thermals abated, leaving the glider without usable lift and forcing the pilot to plan an outlanding.
3. Late field selection: Contrary to recommended practice to commit by 300 m AGL, the pilot changed his initially selected outlanding field at about 200 m above ground in an area with few suitable fields.
4. Short, obstructed field: The ultimately chosen field near Niederhelfenschwil was short, slightly uphill, had trees and a power line on approach, and a road with fence and trees at the far end, with a moderate tailwind in landing direction.
5. Direct low approach: At about 200 m above ground the pilot flew a direct approach over the wooded Eggetsbüel ridge, crossed a high-voltage line at roughly 10 m, and initiated a strong sideslip to lose height.
6. Long float in tailwind: Despite the uphill slope, the glider floated low for a long distance in the tailwind and touched down only about 20 m before the road without being fully held off.
7. Outlanding - damage: During the ground roll the glider crossed the road, struck a wire fence and then collided with an apple tree, damaging the wings but causing no injuries.