Incident Overview
After landing to refuel, the pilot made an inadequate effort to remove airframe ice and snow that had accumulated while on the ground before departing for his final destination. The airplane crashed within two miles of the airport. The pilot's last radio communication received was that he was 'going down.'
Witness Observations
A witness, identified as the refueler, observed that about a half inch of somewhat moist snow had accumulated on the wings of the airplane prior to the time he fueled the airplane, necessitating brushing snow away from the fuel caps. The witness stated that after wiping the snow off, there was still a covering of rough ice on the upper surface of the wing. During the fueling, he noticed that none of the ice on the wing had melted; the ambient temperature at the time of the accident was minus 1 degree Celsius.
The witness also reported that after refueling the airplane, he looked at the right wing leading edge and pointed out some rough ice behind the area that the pilot had cleared, both on top and bottom of the wing. The pilot had rubbed his hand over the rough area, commenting that there wasn't enough ice to make any difference, before attempting his takeoff.
Post-Crash Examination
Post-crash examination of the engine revealed no evidence of pre-impact malfunction.