What happened
During a night IFR approach, the pilot reported the airport in sight. At the time of departure, weather conditions were reported as 500 feet overcast with visibility restricted to 1.5 miles in freezing drizzle. During the en route climb, the pilot was unable to reach the assigned altitude of 9,000 feet due to structural icing. Additionally, the pilot noted an uncommanded decrease in RPM in the left engine.
The pilot notified Air Traffic Control that he could not maintain altitude and requested an immediate return to the departure airport. While turning from left base to final for the landing runway, the aircraft entered a stall. Although the pilot recovered from this initial stall and attempted to place the aircraft in a field, a second stall occurred a few feet above the ground, resulting in the crash on airport property. The pilot was not injured.
The investigation
A post-accident inspection of the aircraft revealed ice buildups on the leading edge of all airfoil surfaces and on the underside of the wings. Investigators found no mechanical defects in the left engine or the propeller system.