What happened
On July 3, 2010, a pilot was conducting a flight from St. Georgen, Austria, to Vilshofen, Germany. After landing at Vilshofen at approximately 15:19, the pilot remained on the ground for about 90 minutes. During a conversation with the airfield manager while paying landing fees, the manager noted that the pilot's hands appeared to be trembling.
At approximately 16:50, the pilot departed Vilshofen on runway 32 for the return flight to St. Georgen. The aircraft was held at the runway threshold for about five minutes due to arriving traffic. Shortly after takeoff, at approximately 16:55, the Cherry BX-2 crashed approximately 2.5 kilometers west of the airfield near Hundsöd. The aircraft struck a downward-sloping field at a high speed and steep pitch, resulting in the death of the pilot and the total destruction of the aircraft.
The investigation
The BFU investigation focused on the aircraft's condition, the pilot's medical history, and the environmental conditions at the time of the accident. The aircraft, an amateur-built composite design, was found to be airworthy and properly maintained, with its most recent annual inspection completed in October 2009.
The investigation also examined the extreme cockpit temperatures. On the day of the accident, ambient temperatures were approximately 30-32°C. Because the aircraft featured a forward-folding canopy instead of a standard sliding canopy, the pilot could not open the canopy for ventilation while the engine was running during the wait at the runway threshold. The BFU noted that cockpit temperatures in such aircraft can rise significantly above ambient levels under direct sunlight.
Findings
- The pilot had a significant medical history, including evidence of an old myocardial infarction and atherosclerosis.
- High ambient temperatures and the lack of effective cockpit ventilation likely led to extreme heat stress within the cockpit.
- The BFU concluded that the accident was caused by a probable loss of control during the departure phase, potentially triggered by a medical emergency, such as a heat-induced collapse or fainting, due to the intense heat and the pilot's cardiovascular condition.