What happened
On July 10, 2006, at 14:25, an IkarUS C42 ultralight aircraft equipped with floats was involved in a fatal accident in Aska, Sodankylä. The pilot was conducting a cross-country flight from the Kitinen river to a landing site at a friend's cabin on the same river.
While performing the second circuit of the landing site, the aircraft encountered a tailwind component. As the pilot initiated a left turn, the aircraft suddenly rotated around its longitudinal axis and entered a vertical dive into the ground. The impact caused severe damage to the aircraft and resulted in the immediate death of the pilot. The aircraft's engine was found to be in good working order, and no fire occurred at the scene.
The investigation
The investigation examined the pilot's recent flight history, the prevailing weather conditions, and the mechanical state of the aircraft. Investigators noted that while the pilot held a valid license and medical certification, recent experience in floatplane operations was limited.
Technical examination of the wreckage in Rovaniemi revealed that the aircraft had been recently washed, which may have introduced water into the pitot-static system. Although no water was found in the system during the investigation, previous flights had exhibited a sticking airspeed indicator. The investigation also reviewed the wind conditions, which were characterized as strong and gusty, posing significant challenges even to rescue helicopter crews.
Findings
- The immediate cause of the accident was the loss of control of the aircraft due to strong, gusty winds.
- The pilot's limited recent flight experience acted as a contributing factor.
- The possibility that a malfunctioning airspeed indicator contributed to the accident could not be ruled out, as the instrument had shown signs of sticking in previous flights.
- The weather conditions, specifically the high wind and gusts, were significant contributing factors to the loss of control during the turn.