What happened
Prior to the accident, the pilot moved the aircraft from a heated hangar, where temperatures were maintained at approximately 60 degrees Fahrenheit, to an outdoor ramp. The aircraft remained parked outside for at least 45 minutes in sub-freezing temperatures with light to moderate snow falling. During this period, snow accumulated on the airframe, and snow that had melted from the warm surface refrozen as ice. The pilot did not clear this accumulation before attempting takeoff.
During the takeoff roll, the ground run was noted as being longer than usual. The aircraft type reached an indicated airspeed of 100 knots before lifting off, momentarily touching the runway again before a second liftoff. Shortly after the second liftoff, the aircraft entered a steep right bank. As the initial climb continued, the aircraft experienced rapid oscillations between steep left and right bank angles and failed to gain significant altitude. The passengers reported the aircraft was shuddering and felt as though it might stall.
After the pilot lowered the nose to achieve level flight, a 180-degree left turn was initiated toward the downwind side of the runway. During this maneuver, the aircraft again entered a steeper than normal bank angle, though the pilot managed to recover. As the pilot attempted a left turn toward the end of the runway, the aircraft began to shake, yaw, and lose altitude rapidly. Despite the pilot applying full throttle, the aircraft sank at an excessive rate and struck a hangar located roughly 1,300 feet southwest of the approach end of runway 35. There were no fatalities reported among the crew and passengers.
Findings
An examination of the engines and the wreckage revealed no pre-impact mechanical malfunctions or failures.