What happened
On June 19, 2011, a Cri-Cri MC-15 amateur-built aircraft, registration HB-YEC, crashed in a field near Hermenches, Switzerland. The pilot, who was in the process of completing a familiarization program for this specific type, had taken off from Yverdon-les-Bains for a short flight.
During the flight, the pilot performed several aerobatic maneuvers, including multiple left-hand rolls, at altitudes between 3,500 and 4,500 feet. Witnesses in the area observed the aircraft performing a low pass at approximately 100 meters, followed by a sharp pull-up and a wingover. Shortly before the impact, witnesses reported a sudden change in engine sound, suggesting both engines had stopped. The aircraft then entered a steep dive and struck the ground in a rapeseed field. The impact resulted in the death of the pilot and the total destruction of the aircraft.
The investigation
Investigators examined the wreckage and the aircraft's technical components. The inspection of the two engines, carburetors, and ignition systems revealed no mechanical failures or defects that could have caused an engine shutdown. The airframe and flight controls also showed no evidence of structural failure prior to the impact.
Digital evidence played a crucial role in the reconstruction of the flight. The pilot's mobile phone was recovered from the crash site. Analysis of the device showed that the pilot had recorded ten short video sequences of his aerobatic maneuvers. The footage confirmed the aircraft was performing rolls at high engine RPMs. Furthermore, the investigation found that the aircraft's weight and balance were outside of the prescribed limits at the time of the accident.
Findings
- The accident was caused by a collision with the ground following a loss of control, the specific origin of which could not be determined.
- The pilot was performing unauthorized aerobatic maneuvers in an aircraft not certified for such flight.
- The pilot's training and familiarization with the Cri-Cri MC-15 were not yet complete.
- The use of a mobile phone during flight likely contributed to the accident, as video evidence showed the pilot was holding the device with one hand while maneuvering the aircraft.
- The aircraft was operating outside of its permitted weight and balance limits.