K 8 B Kollision mit Seil nahe Wolfenschiessen während Trainingsflug

Am 7. Juni 1976 kollidierte ein Alexander Schleicher K 8 B während eines Trainingsflugs in der Nähe von Wolfenschiessen, Schweiz, mit einem Transportseil. Der Pilot, der nur begrenzte Flugerfahrung hatte, flog in etwa 60 Metern Höhe, als der rechte Flügel das Seil traf. Der Aufprall verursachte erhebliche Schäden am Flügel, und das Segelflugzeug stürzte ab, was zu schweren Verletzungen des Piloten führte. Die Untersuchung stellte unzureichende Flugvorbereitung und die Nichteinhaltung der Mindestflughöhe als beitragende Faktoren fest. Das Segelflugzeug wurde bei dem Unfall zerstört.

1. Aerotow ridge flight: The pilot aerotowed from Buochs and then ridge-soared up the northwest flank of the Buochserhorn to summit height before proceeding south along the east side of the Engelberg valley behind a lead glider.
2. Low experience pilot: The 18-year-old pilot had only 18:42 hours total time, limited solo experience on type, and was flying without instructor supervision under a short-term permit.
3. Poor obstacle planning: Before departure he did not study the obstacle chart or otherwise check for cables and other airfield obstacles along the intended route in the mountainous, obstacle-dense Engelberg valley.
4. Low ridge height: While following the lead glider along the valley side, he flew close to the slope at about 60 m above ground without having ensured there was no collision risk with obstacles.
5. Turn into lift zone: North of Chlei Gigi, upon noticing an area of lift, the pilot turned left toward the updraft area and immediately encountered an unmarked transport cable across his flight path.
6. Wing strikes cable: The glider passed just under the right-sloping cable but the right wing struck it about one metre inboard of the tip, tearing off a large outer wing section that remained hanging on the cable and causing the cockpit canopy to depart.
7. Crash - serious injury: Following the structural damage from the cable strike, the glider became uncontrollable and crashed near Chlei Gigi at about 1640 m elevation, seriously injuring the pilot and destroying the aircraft.