What happened
During preflight inspections, the pilot observed ice and frost adhering to the aircraft. After applying glycol, the pilot polished and brushed off the frost. Prior to takeoff, the engines were warmed up while remaining in the traffic pattern to ensure all systems were operational and to clear any remaining ice from the airframe. During the takeoff roll, the pilot utilized less than maximum power. The tail of the aircraft lifted approximately three-quarters of the way down the runway. As the end of the runway approached, additional power was applied, and the aircraft achieved lift-off.
Once a positive rate of climb was established, the landing gear was retracted. Shortly after the gear was raised, the pilot experienced a sensation of the aircraft mushing, similar to a stall. Despite adding more power, the aircraft continued to mush and subsequently impacted terrain with power applied to both engines. The aircraft came to rest in an open field located approximately one-quarter mile from the end of the runway. Following the accident, ice was observed adhering to most of the aircraft.