What happened
On September 9, 2005, at approximately 16:45, an Eurocopter SA 342 J Gazelle, registration F-GEST, was performing a post-maintenance test flight at Albertville aerodrome. The flight was being conducted by a pilot accompanied by a mechanic. Following a brief initial flight, the crew began a second short-duration flight.
During the return to the aerodrome, witnesses on the ground observed the helicopter flying at a high speed on a tailwind approach near runway 2/3. Shortly after crossing the threshold of runway 23, the aircraft entered a steep right-hand turn at an estimated altitude of 50 meters. After completing approximately 90 degrees of the turn in a nearly horizontal plane, the aircraft suddenly entered a sharp nose-down attitude. The helicopter subsequently struck a grove of trees near the runway threshold and caught fire.
The investigation
Investigators examined the wreckage and the site to determine the cause of the impact. The wreckage showed that the F-GEST had struck the ground with a significant nose-down and right-wing-low attitude. Technical inspections of the hydraulic system, the three main servocommandes, the rear servocommande, and all warning lights revealed no mechanical malfunctions. Furthermore, the aircraft was found to be within the manufacturer's specified weight and balance limits.
Medical examinations and an autopsy were conducted to assess the health of the crew. The autopsy revealed that the pilot had suffered a coronary-related cardiac event prior to the impact. Toxicological analysis indicated the pilot was taking medication to manage cholesterol levels. Additionally, investigators reviewed the pilot's most recent medical examination from June 2005, which included an electrocardiogram and cholesterol testing.
Findings
- The primary cause of the accident was the pilot's sudden cardiac event caused by coronary artery disease.
- The physical strain of performing a steep, high-G turn likely precipitated the heart failure.
- The pilot's previous medical examination, while including standard cardiac and cholesterol screenings, failed to detect the specific severity of the coronary lesions.
- There were no technical or mechanical failures contributing to the loss of control.