What happened
On June 27, 1998, a pilot was participating in a flight demonstration at Samedan Airport in Switzerland. After a delay of approximately 30 minutes on the ground with engines running, the pilot departed on runway 21 in a homebuilt Cri-Cri MC15, registration HB-YGD.
Following the takeoff and climb, the aircraft reached an altitude of approximately 60 meters. The pilot initially executed a gentle left turn toward a nearby farm. Shortly thereafter, following instructions from the air traffic controller to begin the demonstration immediately, the pilot initiated a right turn to align the aircraft with a taxiway. During this maneuver, the aircraft experienced a left wing drop, prompting a right-hand correction. This correction caused the nose to drop, leading to a significant loss of airspeed. Although the pilot managed to pull up 20 meters above the ground, the aircraft eventually lost control and struck the terrain at a 45-degree angle. The pilot sustained fatal injuries.
The investigation
The investigation examined the aircraft's technical state, the pilot's experience, and the environmental conditions at the time of the accident. The Cri-Cri MC15 was a single-seat, twin-engine amateur-built aircraft. Investigators found that the aircraft's weight was 180 kg, which was the maximum allowable limit. The engines were functioning at full throttle at the time of impact, and the aircraft's technical inspections were up to date.
Meteorological data revealed winds from 210 degrees at 13 knots, with gusts reaching 19 knots. The investigation also noted that the aircraft was operating at an altitude of 1707 meters, where reduced engine performance is expected due to thinner air. Additionally, a jet aircraft, a Hunter, had performed a low-level demonstration flight just one minute prior to the accident.
Findings
- The pilot lost control of the aircraft while performing a maneuver at an insufficient altitude.
- Wind gusts and shifting wind direction (transitioning from headwind to tailwind) significantly impacted the aircraft's stability during the turn.
- Reduced engine power resulting from the high altitude contributed to the loss of airspeed.
- The aircraft was operating at its maximum permitted weight of 180 kg.
- The air traffic controller did not inform the pilot of the measured wind gusts.
- Possible wake turbulence from the preceding Hunter jet flight may have been a contributing factor.