What happened
On August 22, 2023, a Schempp Hirth Ventus 2C glider, registered F-CIGJ, was performing a towed takeoff from runway 36R at the Issoire - Le Broc aerodrome. During the climb, the tug pilot noted that the glider was struggling to maintain alignment behind the tow aircraft. Approximately two minutes and thirty seconds into the flight, at an altitude of 350 meters, the glider pilot released the tow cable earlier than usual.
As the glider transitioned through the downwind and base legs of the aerodrome circuit, witnesses and the tug pilot observed irregular flight characteristics, including significant oscillations in pitch and altitude. During the final approach, the glider overshot its path and, despite the extension of air brakes, suddenly pitched down and collided almost vertically with a cornfield a few degrees from the runway threshold. The impact resulted in the death of the pilot and the destruction of the aircraft.
The investigation
The investigation examined the aircraft wreckage, meteorological conditions, and the medical history of the pilot. The wreckage showed severe structural failure, with the fuselage rupturing at the wing roots and the tail section separating.
Investigators noted that the flight took place during an intense heatwave, with temperatures at the aerodrome reaching 36°C. The cockpit of the F-CIGJ lacked an air-conditioning system and was not airtight, exposing the pilot to high ambient heat and humidity. An autopsy of the pilot revealed advanced generalized arterial atherosclerosis, characterized by a 70% reduction in the caliber of the coronary arteries and old scarring of the heart muscle. No drugs or alcohol were found in the pilot's system.
Findings
- The extreme heat and high humidity within the poorly ventilated cockpit likely increased the pilot's physiological workload and dehydration levels.
- The pilot's underlying cardiovascular disease likely caused a period of incapacitation or faintness.
- The early release of the tow cable and the erratic flight maneuvers observed during the circuit were indicative of the pilot's deteriorating physical state.
- The pilot was likely unaware of the severity of his underlying heart condition.