What happened
On August 16, 2016, a Bristell ultralight, identified as 44-AXM, departed from La Baule Escoublac aerodrome for local circuit training. The pilot, operating for a flight school, completed three circuits before announcing a downwind leg for runway 11. Shortly after this radio transmission, a witness located approximately 3 NM north of the airfield observed the aircraft flying at an extremely low altitude. The aircraft then disappeared from view, and the sound of an impact was heard moments later.
The aircraft struck the steep wall of an abandoned quarry that had been converted into a water reservoir. The impact resulted in the death of the pilot and the total destruction of the aircraft.
The investigation
The investigation focused on the wreckage, the aircraft's maintenance history, and the pilot's medical status. Investigators found the airframe, wings, and engine to be intact and free of external deformation. The flight controls were functional prior to impact, and fuel was present at the fuel filter, indicating no mechanical failure or engine starvation. The aircraft's emergency parachute had deployed, though the pyrotechnic charge had not been triggered.
Regarding the pilot, the investigation revealed that while he had held a fixed-wing license in the past, he had only recently obtained his ultralight license in 2015. Medical examinations of the pilot's body identified advanced ischemic heart disease, characterized by extensive myocardial fibrosis. This condition is known to cause cardiac arrhythmias and reduced tolerance to high temperatures.
Findings
- The investigation found no evidence of mechanical malfunction or structural failure in the Bristell.
- The pilot suffered from advanced ischemic heart disease, which can lead to sudden incapacitation.
- The pilot's medical history included chronic arteriopathy, a condition that would disqualify him from a Class 2 medical certificate required for heavier aircraft.
- The lack of mandatory aeronautical medical oversight for ultralight pilots may prevent pilots from receiving guidance on how evolving health conditions affect flight safety.