Ka 8 incident at Blauen, Switzerland: pilot fatality following in-flight medical emergency

On April 4, 1965, a Ka 8 glider took off from Dittingen Airfield for a thermic flight near Blauen, Switzerland. Approximately 20 minutes after release, the aircraft entered an uncontrolled spiral descent and crashed into trees on the south slope of Blauen. The pilot was found deceased at the scene, with an autopsy confirming a fatal heart attack during flight. The glider sustained significant damage, and two trees were felled during recovery operations.

1. Aerotow thermaling flight: The pilot aerotowed from Dittingen at 14:59 local time in Ka-8 HB-630 for a thermic soaring flight at the Blauen and released about 350 m above the airfield to begin circling in lift.
2. In-flight heart attack: While circling and gaining height over the south slope of the Blauen, the pilot suffered a sudden, rapidly fatal heart infarction that incapacitated him.
3. Uncontrolled spiral descent: Following the pilot’s incapacitation, the glider began descending in irregular, apparently uncontrolled spirals from its thermalling position over the south slope of the Blauen.
4. Crash - fatal: At about 15:20 local time the glider struck the treetops on the south slope of the Blauen and remained hanging in the trees, fatally injuring the pilot and heavily damaging the aircraft.