Accident Summary
On a night with light wet snow falling, a Cessna 208B departed from an airport. After reaching an altitude of 700 feet above ground level, the airplane entered a steep descent, struck trees, and came to rest inverted. The pilot, who was the only person on board, was killed in the accident.
Sequence of Events
Radar data indicated that the aircraft's liftoff point and initial climb rate were similar to those specified in the flight manual for short field takeoff technique. Two other Cessna 208 airplanes had departed from the same airport earlier: one 13 minutes before the accident aircraft and another 3 minutes before. Radar data showed that both preceding aircraft climbed at a slower rate than the accident airplane.
The accident airplane had been stored in a hangar and was not de-iced prior to departure. A pilot flying an identical airplane with a similar load reported that his own climb rate was lower than normal. Another pilot commented that this was the first wet snow of the season and that the snow was sticking to his engine cowling.
Probable Cause
The official investigation determined the probable cause to be a loss of control in flight after the airplane stalled during climbout. The stall resulted from a loss of lift due to a contaminated wing surface. A contributing factor was the failure of the pilot to de-ice the aircraft before departure.