Kollision in der Luft zwischen Ka 4 Rhönlerche II und SZD-22B über Oberwald, Schweiz

Am 30. Juli 1964 ereignete sich eine Kollision in der Luft zwischen einer Alexander Schleicher Ka 4 Rhönlerche II und einer SZD SZD-22B in der Nähe von Oberwald, Schweiz. Der Vorfall geschah während eines Segelflug-Trainingslagers, das von der Akademischen Fliegergruppe Zürich organisiert wurde. Die Kollision führte zum Absturz der Ka 4 Rhönlerche II, wobei der Pilot tödlich verunglückte, während der Pilot der SZD-22B mit dem Fallschirm abspringen konnte, jedoch schwere Verletzungen erlitt. Die Untersuchung führte die Kollision auf unzureichende Luftraumüberwachung durch beide Piloten zurück.

1. Aerotow — thermaling: After aerotow release over the Oberwalder Blasen ridge, the Rhönlerche II HB-573 began soaring in local lift as part of a training flight with altitude and area limits set by the instructor.
2. Low-time student pilot: The HB-573 was flown solo by a relatively inexperienced student pilot with about 11 hours total time, operating in alpine terrain under training constraints.
3. Instrument-focused flying: Both pilots were likely concentrating on variometer, airspeed, and slip indication to optimize weak lift and minimize sink, reducing continuous outside visual scanning.
4. Shared lift area: HB-573 and HB-659 were both operating in the same lift area several hundred meters from the Oberwalder Blasen slope, with at least one witness indicating they were circling one above the other, possibly in opposite directions.
5. Inadequate lookout: Neither pilot maintained sufficient all-round airspace surveillance to detect the other glider in time to adjust circling direction or take effective avoiding action.
6. Frontal wing collision: The two gliders collided frontally with the leading edges of their left wings striking each other at about mid-span, causing structural failure of both left wings.
7. Crash - fatal: HB-573 immediately entered a steep spin and crashed on the slope, killing the pilot, while HB-659 broke up and its pilot bailed out with serious injuries.