What happened
On April 11, 2012, at approximately 13:2 and 25, an Ikarus C42B ultralight aircraft crashed into the ice of Lake Orivesi in Rääkkylä. The aircraft, which was equipped with inflatable floats, had departed from Kitee earlier that day with the intention of visiting a summer cottage in Nieminen. Evidence found on the ice indicated that the aircraft had landed near the cottage and subsequently attempted a takeoff from the frozen surface.
During the flight, the aircraft struck the ice at a steep angle with a slight left bank. The impact triggered a violent fire that completely destroyed the aircraft. The pilot and the passenger, both 74 years old, perished in the accident. There were no eyewitnesses to the event. The wreckage was discovered by search teams at approximately 20:00, several hours after a relative reported the aircraft missing to the emergency center.
The investigation
Investigators examined the wreckage and the flight conditions. While the engine was running at the time of the crash, the intense fire prevented investigators from entirely ruling out a technical malfunction. The weather was suitable for VFR flight, though strong and gusty south-southeast winds were present, potentially reaching or exceeding the limits specified in the aircraft's flight manual.
The investigation also focused on the aircraft's airworthiness. It was determined that the aircraft's weight and balance certification for float configuration had expired. Furthermore, the aircraft was significantly overweight; the estimated takeoff weight was 560 kg, whereas the maximum allowable takeoff weight for this type of two-seat ultralight seaplane is 495 kg.
Findings
- The loss of control of the aircraft under challenging conditions was the probable cause.
- The aircraft was operating significantly overweight, which increased the stall speed.
- The pilot had sufficient total flying experience, but had very limited recent flying experience.
- Strong, gusty winds contributed to the difficulty of maintaining control.
- The pilot's diminished reaction times, noted by acquaintances, were a contributing factor.
- The aircraft was not airworthy due to an expired weight and balance certificate.
- The possibility of an acute medical emergency during the flight could not be ruled out.