What happened
On August 3, 2002, at approximately 15:00, a Dyn’Aéro MCR 01 (registration F-PQUI) crashed near Pierre-sur-Haute, France, during a cross-country flight. The pilot departed from Guéret around 14:00, intending to fly to Grenoble le Versoud via Clermont-Ferrand and Saint-Rambert-d’Albon.
During the flight, the pilot communicated with Clermont Approach, initially transiting at 2,200 feet. Seeking to clear local terrain, the pilot requested and subsequently climbed to 4,500 feet. Witnesses on the ground, positioned at an altitude of approximately 5,000 feet, observed the aircraft flying south through a valley at an altitude lower than their own. They observed the aircraft enter a steep left-hand turn, after which it disappeared behind a ridg_line. Shortly thereafter, the sound of an impact with trees was heard. There were no reports of engine power fluctuations from witnesses.
The investigation
Investigators examined the wreckage and determined that the aircraft had very low horizontal airspeed at the moment of impact. The aircraft, an amateur-built kit plane, was powered by an 80-horsepower JPX 4T X 75 A engine. A portable GPS was recovered from the wreckage.
Evidence indicated that the pilot had departed with 47 liters of fuel, with a known consumption rate of 16 liters per hour. The investigation also considered the terrain configuration, noting that the valley where the wreckage was located narrows to a pass at 1,428 meters. The investigation established that the aircraft's flight path and the narrowness of the valley likely forced a reduction in turn radius and airspeed, potentially leading to a stall.
Findings
- The pilot selected an unsuitable flight route given the prevailing meteorological conditions.
- There was a delayed decision to perform a turnaround to avoid the terrain.
- The pilot misjudged the distance relative to the surrounding high ground.
- The aircraft's speed decreased significantly during the maneuver, likely reaching the stall speed.