What happened
On July 15, 2005, at approximately 11:00 local time, an Air Creation Safari GT BI 582 ultralight aircraft, registration 47-FE, crashed in the vicinity of Loudenvielle, France. The flight, which was a private trip, began earlier that morning in Monflanquin. After a stop near Lannemezan for refueling, the pilot and one passenger continued their flight over the Pyrenees.
While navigating a north-south oriented valley, the pilot approached an eastern-facing slope where thermal updrafts were developing. In an attempt to utilize these thermals to assist a westward turn, the pilot entered a narrow valley. However, the aircraft was unable to maintain sufficient altitude. The pilot attempted to turn toward more open airspace, but the aircraft struck the treetops and subsequently crashed into the ground within a forested area at an altitude of 1,560 meters.
The investigation
The investigation focused on the flight path and the meteorological conditions at the time of the accident. Investigators examined the aircraft's interaction with the terrain and the atmospheric conditions present near the site. It was noted that the site was characterized by steep, wooded slopes and nearby cliffs. The pilot and passenger were unable to reach the valley floor to seek assistance for seven hours following the impact.
Findings
At the time of the accident, the weather was reported as CAVOK with a temperature of 21 °C. However, a south wind of 15 to 25 knots was blowing against the Pyrenean terrain, which generates significant turbulence. The investigation determined that the primary cause of the accident was the inadequate management of mountain aerological phenomena. The pilot's attempt to use thermal currents in a narrow valley led to a loss of control at a very low altitude, resulting in the destruction of the aircraft and one minor injury to the pilot.