Karpf Baby Kollision bei Außenlandung nahe Niederhelfenschwil, Schweiz

Am 20. August 1965 war ein Karpf-Flugzeugbau Karpf Baby Segelflugzeug in einen Vorfall nahe Niederhelfenschwil, Schweiz, verwickelt. Der Pilot versuchte eine Außenlandung aufgrund abnehmender Thermik und wählte ein nicht ideales Feld. Während der Landung kollidierte das Segelflugzeug mit einem Zaun und einem Baum, was zu Schäden am Flugzeug führte. Glücklicherweise wurden keine Verletzungen gemeldet. Der Vorfall verdeutlicht die Herausforderungen bei der Auswahl geeigneter Außenlandungsplätze in komplexem Gelände.

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.