On September 14, 2002, about 1730 Alaska daylight time, a tundra tire-equipped, experimental homebuilt Gardner Kitfox airplane, N996DG, sustained substantial damage when it collided with trees during a forced landing after takeoff. The flight was departing the Gold King Airport, about 37 miles south-southeast of Fairbanks, Alaska, and was enroute to Fairbanks. The airplane was being operated as a visual flight rules (VFR) cross-country personal flight under Title 14, CFR Part 91, when the accident occurred. The airplane was operated by the pilot. The private certificated pilot, and the sole passenger, were not injured. Visual meteorological conditions prevailed. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on September 18, the pilot reported that he was departing the gravel surfaced runway, and had climbed to about 125 feet above the ground when the engine suddenly lost power. The engine, a Rotax 582, did not completely quit, but lost significant power. The pilot selected a forced landing area ahead of the airplane. During the forced landing, the airplane collided with several trees. The airplane received damage to the wings and empennage. During a telephone conversation with the NTSB IIC, on April 1, 2003, the pilot reported that a postaccident inspection of the engine revealed damage to one of the engine's main crankshaft bearings. The bearing appeared to have rotated in its bearing seat.