Ventus C drops nose progressively through ridge turn and impacts vertically

A glider pilot with only ~3 h on type was fatally injured when his Ventus C, circling on the alpine ridge at Wistätthorn, dropped its nose progressively through ~270° of turn and dived vertically into the ground at roughly double normal airspeed; aircraft destroyed. Witnesses watched the bank stay roughly normal while the nose progressed steeper; the last ~100 m were near-vertical. No technical defects (airbrake damage was post-impact). Autopsy found pre-existing coronary disease that could cause loss of consciousness at altitude.

1. Camp; ridge soaring at Wistätthorn: The pilot launched from Zweisimmen for an alpine summer-camp training flight, later ridge-soaring the Wistätthorn with two other camp gliders, flying back and forth east of the crest.
2. Normal turn; nose drops progressively: Witnesses descending the ridge watched the glider enter a normal turn at normal speed; over the next 90° the nose began to drop, and one initially thought it was a loop.
3. ~270° of turn with steepening nose-down: Through about 270° of continued turning the bank stayed roughly normal but the nose-down attitude kept increasing; no recovery input was visible.
4. Last 100 m vertical at double airspeed: Final ~100 m were near-vertical at roughly twice normal airspeed; witness could look directly at the cockpit and see the pilot before impact.
5. Pre-existing coronary disease: The autopsy found pre-existing coronary disease that, especially with relative hypoxia at altitude, could cause myocardial undersupply and loss of consciousness at any time.
6. Vertical impact; pilot fatal: The glider embedded vertically in the ground and was destroyed; the pilot was fatally injured. The cause was probably medical, though not determinable with certainty.