LS-1C collision with rock face near Fletschhorn, Switzerland
On August 9, 1985, an LS-1C glider collided with a rock face on the west flank of the Fletschhorn massif in Switzerland. The pilot, who had taken off from Münster airfield for a 460 km flight, was fatally injured in the accident. The glider was destroyed upon impact at an altitude of 3350 meters. The investigation noted the pilot's pre-existing medical conditions, including arteriosclerosis and lung issues, which may have contributed to the accident. The report recommended reviewing medical checks for glider pilots.
- Cross-country cruise: After an aerotow departure from Münster for a planned 460 km task, the pilot continued a long cross-country flight in the Alps, later remaining at about 3350 m near the Fletschhorn late in the afternoon.
- Suboptimal soaring conditions: Forecast and actual conditions provided only slow progress and weak lift, encouraging flying close to terrain to maintain height in the mountainous area.
- Pilot health limitations: The pilot had pre-existing arteriosclerosis and significant chronic lung disease, was convalescent from a recent flu, and flew for many hours at altitude without using the onboard oxygen system.
- Dehydration and low energy: On this long performance flight the pilot forgot to take his usual in-flight food and drink, predisposing him to dehydration, blood thickening, and hypoglycaemia over several hours.
- Low margin ridge flight: While flying along the west side of the Fletschhorn massif, the glider was flown close to a steep, irregular rock face at roughly constant altitude around 3350 m, leaving little clearance from the terrain.
- Impaired judgement/vision: Likely combined effects of chronic disease, oxygen deficit, dehydration, and low blood sugar may have degraded the pilot’s judgement and visual performance while assessing terrain clearance near the ridge.
- Crash - fatal: At approximately 17:47 the glider impacted a rock wall at the Jegigrat on the west side of the Fletschhorn at about 3350 m, destroying the aircraft and fatally injuring the pilot.