Kollision in der Luft zwischen Karpf Baby und Grunau Baby über Weiningen während eines Trainingsflugs

Am 12. April 1961 kam es zu einer Kollision in der Luft zwischen einem Karpf-Flugzeugbau Karpf Baby und einem Edmund Schneider Grunau Baby in der Nähe von Weiningen, Schweiz. Beide Segelflugzeuge waren im Rahmen eines Segelfluglagers der Segelfluggruppe Winterthur in Trainingsflügen involviert. Die Kollision ereignete sich in etwa 750 Metern Höhe, während beide Segelflugzeuge im gleichen Gebiet thermikflogen. Der Pilot des Karpf Baby konnte sich mit einem Fallschirmabsprung retten, aber der Pilot des Grunau Baby wurde tödlich verletzt. Die offizielle Untersuchung führte die Kollision hauptsächlich auf unzureichende Luftraumüberwachung durch den Piloten des Grunau Baby zurück.

1. Aerotow — thermaling: After an aerotow launch at 12:58 and release around 13:02, the HB-497 pilot began thermaling and rapidly gaining height in the established lift area north of Frauenfeld.
2. Shared thermal use: HB-497 entered and circled in the same thermal column where HB-512 was already circling above with the same left-hand turn direction, creating vertical proximity in the same air mass.
3. Limited experience & workload: As a relatively low-time student pilot performing a required thermaling task, the HB-497 pilot was likely highly focused on climbing performance and instrument indications, increasing susceptibility to neglecting lookout.
4. Inadequate lookout above: While climbing in the thermal, the HB-497 pilot began or continued circling without adequately monitoring the airspace above, failing to detect the higher HB-512 despite converging vertically.
5. Continued climb under HB-512: HB-497 continued to climb in the same left-hand circle beneath HB-512, with the vertical separation steadily decreasing as observed by a witness, and with the HB-512 pilot no longer keeping HB-497 continuously in sight.
6. Converging flight paths: As HB-497 rose and HB-512, likely slipping outward and no longer climbing, both gliders’ circular paths converged laterally and vertically until HB-497’s right wing leading edge appeared just below HB-512’s right wing, leaving no time to avoid impact.
7. Crash - fatal: HB-497’s forward fuselage struck the trailing edge of HB-512’s right wing, tearing it off; HB-512 entered an uncontrolled descent from which the pilot bailed out safely, while the severely damaged HB-497 went into a steep dive and crashed, fatally injuring its pilot.