What happened
On April 14, 2007, at approximately 17:15, a Colomban MC 15 Z was performing aerobatic maneuvers within the designated aerobatic zone near Amboise aerodrome. The pilot had departed the airfield at 16:45, initially performing low-altitude passes and various rolls. After several minutes, the aircraft returned to the aerobatic zone at an altitude of approximately 3,000 feet.
During the sequence, the pilot initiated a left roll, followed by a vertical climb and a left quarter-roll. During the subsequent leftward banking maneuver, the aircraft entered a rapid, regular left-hand spiral dive with a pitch attitude of approximately 45 degrees. After roughly ten rotations, the aircraft struck the ground approximately 200 meters from the runway.
The investigation
Investigators examined the wreckage and the accident site, determining that the aircraft impacted the ground in a left turn with a slight left bank and a 45-degree nose-down attitude. The inspection of the Colomban MC 15 Z revealed no mechanical anomalies capable of contributing to the accident, although it could not be confirmed if both engines were producing equal power at the moment of impact.
The investigation also reviewed the aircraft's flight manual, which notes that the designer advises against performing inverted flight due to its difficulty, as it requires specific power management between the two engines. Furthermore, the investigation looked into the pilot's medical history, noting that he had begun medication for hypertension in January 2007. While the pilot had not sought a new aeronautical medical assessment, there were no regulatory requirements for him to do so as he felt no physical or mental impairment.
Findings
- The aircraft entered a rapid spiral dive that the pilot was unable to recover from.
- The pilot was taking medication for hypertension, which can affect blood pressure regulation during high G-load maneuvers.
- High-frequency G-load changes can impact baroreceptor sensitivity, potentially leading to physiological distress or loss of consciousness.
- The specific impact of antihypertensive medication on pilot performance during aerobatic maneuvers remains unstudied.