N3248T

On July 2, 2004, about 1715 central daylight time, a Beech model A36, N3248T, piloted by a commercial pilot, was substantially damaged as a result of a forced landing following a loss of engine power and subsequent in-flight fire. The 14 CFR Part 91 business flight was operating in visual meteorological conditions without a flight plan. No injuries were reported. The flight originated from the Mason City Municipal Airport, Mason City, Iowa, at 1630, and was bound for the Joe Foss Field Airport, Sioux Falls, South Dakota.

The pilot reported that about 15 minutes into the flight, while level at 4,500 feet mean sea level, the airplane engine "blew up." The pilot stated that he executed a forced landing on a road. He stated that he kept the landing gear retracted to insure that he could clear a car that was traveling in the opposite direction. The pilot stated that once clear of the car he lowered the landing gear, but due to the low altitude, the landing gear did not fully extend before contact with the road occurred.

Examination of the engine revealed a hole in the top of the crankcase near the number 5 and 6 cylinders. The hole in the crankcase was aligned with the number 6 connecting rod journal. All of the engine accessories remained intact and attached to the engine.

Fractured pieces of the number 6 connecting rod, piston and piston pin were found within the crankcase. The fractured piston exhibited signatures consistent with overload failure. The fracture surfaces of the connecting rod were smeared and no determination could be made concerning the fracture surfaces.

The number 5 piston was lodged within its cylinder. The connecting rod remained attached to the piston. The connecting rod cap was separated from the connecting rod. The fracture surfaces were smeared and no determination could be made concerning the fracture surfaces.

Examination of the main bearings and the connecting rod bearings of the undamaged connecting rods revealed no evidence of oil starvation.