DG-300 Elan low-altitude loss of control; probable sudden medical incapacitation

On 23 June 2010 the pilot of a DG-300 Elan died in a forest east of Les Rochat during a competition task; the aircraft was destroyed. He had felt unwell from the previous evening with headache and circulatory complaints but flew the task anyway. Launched at 13:00 LT from Yverdon, he flew to the Creux-du-Van. During cruise at low altitude the glider lost 200 m in eight seconds in level flight, then made two abrupt left turns and impacted tall pines at ~115 km/h indicated. No distress call was made and no technical defects were identified; the probable cause was sudden in-flight medical incapacitation.

1. Championship task launch from Yverdon: At 13:00 LT on the penultimate day of the Swiss Gliding Championship at Yverdon, the DG-300 Elan launches on aerotow for the day's task; the pilot crosses the start line at 14:35 LT.
2. Pilot unwell since previous evening: From the evening before the flight the pilot has felt unwell, complaining of headache and suspected circulatory problems and skipping dinner. On the morning of the flight he again reports a headache and asks whether the launch could be delayed, but still flies the task; bystanders observe unusual clothing choices (hood pulled tightly over the face) for the mild weather.
3. Sudden 200 m loss in 8 seconds: During cruise at low altitude near the Creux-du-Van, flight data show that the glider loses about 200 m of altitude in eight seconds in apparently level, straight flight — inconsistent with the pilot's usual profile and pointing to an acute event in the cockpit.
4. Two abrupt left turns, high sink: The flight path then shows a brusque left turn with a brief climb, followed by a second left turn with a high sink rate. This phase lasts only 24 to 30 seconds. No distress call is transmitted and no parachute deployment is attempted.
5. High-speed impact in forest: The glider strikes tall pines about 1 km east of Les Rochat with about 40° nose-down pitch and slight left bank at high speed; the airspeed indicator is found jammed at 115 km/h. Tree strikes are visible 3 to 15 m above ground; the wreckage is scattered over about 50 m, and the impact crater is ~60 cm deep. The aircraft is destroyed and the pilot is fatally injured.
6. Probable sudden incapacitation: Examination finds no pre-existing technical defects, mass and CG within limits, no fatigue break in the elevator pushrod. The ELT was carried but not switched on, and the data logger was only enabled mid-flight — both consistent with degraded pre-flight situational awareness. Forensic findings at the wreckage support a sudden in-flight medical impairment as the most probable cause of the loss of control.