Kollision in der Luft zwischen Ka 6 und Club Libelle nahe Münster, Schweiz

Am 18. Juli 1979 kam es während eines Segelfluglagers nahe Münster, Schweiz, zu einer Kollision in der Luft zwischen einer Ka 6 und einer Club Libelle. Die Club Libelle flog enge Spiralen in starker Thermik, als die Ka 6 in denselben Bereich einflog, was zu einer Kollision in etwa 2500 Metern Höhe führte. Die Ka 6 erlitt erhebliche Schäden und musste auf einem felsigen Hang notlanden, was zur Zerstörung des Flugzeugs und leichten Verletzungen des Piloten führte. Die Club Libelle konnte trotz Schäden am linken Flügel sicher auf dem Flugplatz Münster landen. Der Vorfall wurde auf unzureichende Luftraumbeobachtung beider Piloten zurückgeführt.

1. Aerotow thermaling: During a soaring camp at Münster, the Ka 6 HB-650 launched by aerotow at 1112 and began thermaling in the Alps south of the Galmihornhütte.
2. Shared thermal area: Both the Ka 6 and the Club Libelle were circling in the same general lift area south of the Galmihornhütte, later moving to the strong thermal southeast of the Rossboden with about 200 m lateral separation.
3. Poor lookout: While both gliders circled in right-hand turns with different bank angles and circle sizes, the pilots lost visual contact with each other and did not adequately monitor the surrounding airspace.
4. Conflict in thermal: At about 2500 m MSL southeast of the Rossboden, the flight paths of the two gliders converged such that the Club Libelle approached the Ka 6 from behind and slightly left.
5. Ka 6 avoidance maneuver: Seeing the Club Libelle coming up from behind, the Ka 6 pilot attempted to avoid collision by pushing the nose down and turning away.
6. Mid-air contact: During the avoidance maneuver, the underside of the Club Libelle’s fuselage struck the Ka 6’s horizontal tail and then its left wing hit the Ka 6’s rudder, damaging the empennage.
7. Crash - minor injury: Feeling control stick vibrations after the collision, the Ka 6 pilot extended airbrakes and attempted an emergency landing on a rocky slope, where the glider impacted with the left wing, broke up, and slid 30–40 m down the hill, resulting in destruction of the aircraft and minor injuries to the pilot.