SZD-30 Pirat-Absturz in Zweisimmen nach missglücktem Hangflugversuch
Am 22. August 1987 stürzte eine SZD-30 Pirat in der Nähe von Zweisimmen, Schweiz, ab, was zum Tod des Piloten führte. Der Pilot versuchte einen 50 km FAI-Streckenflug unter ausgezeichneten Thermikbedingungen. Nach dem Ausklinken verlief der Flug normal, bis das Segelflugzeug in der Nähe des Fromattgrat auf Schwierigkeiten stieß. In der Gegend herrschten starke Windböen und Turbulenzen. Der Unfall wurde auf unzureichende Flugtaktiken entlang des Hanges zurückgeführt, verstärkt durch Faktoren wie Turbulenzen, geringe Flugerfahrung und mögliche Ermüdung.
- Cross-country thermaling: After an aerotow launch from Gruyère and release over the Schopfenspitze, the pilot conducted a normal cross-country soaring flight via Gros Mont, Gastlosen, Spillgerten and Stockhorn under good thermal conditions.
- Low, turbulent ridge thermaling: Near the Fromattgrat ridge above Zweisimmen, the pilot began circling along the slope in strong southwesterly gusts and turbulence while having difficulty gaining height.
- Low terrain clearance: The glider was flown in close proximity to the sloping terrain, with a probable misjudgment of distance to the ground during ridge circling.
- Limited experience and fatigue: The pilot had relatively low overall and pre-alpine experience and may have been physically fatigued after about 2.5 hours of flight, possibly influenced by a low level of alcohol in his system.
- Continued tight circling: The pilot continued to circle at least three times along the ridge in the turbulent conditions instead of breaking off to a safer height or terrain clearance.
- Loss of safe margin: While circling close to the slope in turbulence, the glider lost its remaining safety margin to the terrain and descended toward the hillside.
- Crash - fatal: The glider impacted almost perpendicularly into the 25° grass slope at about 2007 m near the Fromattgrat, was destroyed, and the pilot sustained fatal injuries.