20010303002509A

(-23) During cruise flight the pilot reported that the engine started to run rough and shake excessively, at which time the pilot said that the throttle was reduced to half to try to get the engine to maintain some form of power to reach a suitable landing site. The pilot reported that retarding the throttle to half did not help and the engine quit at this time with oil covering the windshield and smoke filling the cockpit. The pilot then stated that the fuel was turned off to the enigne and conducted an emergency landing in the trees. The pilot said that after landing the cowling was removed and a hole was noted in the top of the left side of the engine crankcase between the number 2 and number 4 cylinders. (-19) on March 3, 2001, about 1300 Alaska standard time, wawheel/ski equipped Helio H-295 airplane, N42DC, sustained substantial damage during a forced landing about 20 miles south of clear, Alaska. The airplane was being operated as a visual flight rules (VFR) positioning flight under title 14, CFR part 91, when the accident occurred. The airplane was registered to, and operated by, wright air service, inc., fairbanks, Alaska. The solo airline t ransport pilot was not injured. Visual meteorological conditions prevailed, and a VFR flight plan was filed. The flight originated at the stampede airstrip, about 1250, and was enroute to fairbanks. During a telephone conversation with the national transportation safety board investigator-in-charge on MARCH5, the pilot reported that while in level, cruise flight, the engine began to run rough, and lose power. The pilot said that while performing the engine emergency procedures, he smelled smoke in the cabin, and noted a substantial amount or engine oil on the windscreen. The airplane collided with trees during a subsequent forced landing, and sustained substantial damage to the wings, fuselage and empennage. The pilot stated that a postaccident inspection of the engine revealed a fist-sized hole on the left side of the engine crankcase.