Ka 4 Rhönlerche II Kollision mit Schleppseil während der Landung in Zürich-Brunau
Am 25. August 1989 war eine Ka 4 Rhönlerche II in eine Kollision während einer Flugschau in Zürich-Brunau verwickelt. Das Segelflugzeug, das einen Piloten und einen Passagier an Bord hatte, traf beim Landeanflug auf ein Schleppseil eines anderen Segelflugzeugs. Die Kollision führte dazu, dass der rechte Flügel abgetrennt wurde, was einen unkontrollierten Absturz aus etwa 30 Metern Höhe zur Folge hatte. Der Pilot erlitt tödliche Verletzungen, während der Passagier schwer verletzt wurde. Die offizielle Untersuchung führte den Unfall darauf zurück, dass der Pilot das vorgeschriebene Landemuster nicht eingehalten hatte.
- Winch launch flights: During an airshow at Allmend Brunau, the Rhönlerche II HB-571 conducted a winch launch as the first of two closely spaced passenger flights using a double-drum winch.
- Second cable still airborne: After HB-571 released its first-launch cable and while it was still in the circuit, the second glider was launched on the remaining winch cable, which was still being reeled in and not yet fully on the ground.
- Abbreviated landing circuit: Before the second winch cable was fully retrieved, the pilot of HB-571 initiated an abbreviated landing circuit that took the glider across the winch area instead of following the prescribed pattern.
- Right wing hits cable: While flying crosswise in front of the winch, the right wing of HB-571 struck the still-descending second winch cable beneath its parachute, which sawed through the outer wing section at about 35 m height.
- Loss of control and fall: The collision with the cable caused an immediate loss of control, and the glider entered an uncontrolled right-rolling descent from approximately 30 m, impacting nearly nose-first.
- Crash - fatal: The glider was destroyed in the vertical impact, the pilot was fatally injured, and the passenger sustained serious injuries.