DEN00LA064

For the second flight of the homebuilt airplane, the pilot/builder took off and remained in the traffic pattern. While on the downwind leg and approaching the base leg turn, the engine began 'misfiring and/or running very rough.' Smoke filled the cabin, and the engine seized shortly thereafter. During the forced landing, the airplane clipped a high stack of PVC pipes and impacted the ground inverted. Postaccident investigation disclosed the pilot had removed the engine oil pressure sending unit from the engine oil pressure port, located on the right side of the engine-driven oil pump housing. He then installed a common automotive brass T-fitting, to which he attached both the oil pressure sending unit and a Hobbs hour meter fluid pressure-activated switch. The T-fitting failed in the pipe thread, flush with the pump housing exterior surface. The arm of the 'sending unit assembly' was about 4.5 inches long, with an estimated weight of about 7 ounces. The path of the engine cooling air directed the leaking oil to the cabin air heat muff, where it was burned by the muffler prior to entering the cabin, accounting for the smoke in the cabin.

On March 24, 2000, at 1132 mountain standard time, a Johnson Zodiac CH 601 HDS, N984J, registered to and operated by the pilot, was destroyed when it collided with objects and terrain 100 yards south of the southwest boundary of Salt Lake City Municipal 2 Airport, Salt Lake City, Utah. The private pilot, the only occupant, received minor injuries. Visual meteorological conditions prevailed for the personal flight, and no flight plan had been filed for the personal flight being conducted under Title 14 CFR Part 91. The flight originated from Salt Lake City Municipal 2 Airport just before the accident.

According to the pilot's accident report, this was the airplane's second flight. He took off on runway 34 and remained in the traffic pattern. While on the downwind leg and approaching the base leg turn, the engine began "misfiring and/or running very rough." Smoke filled the cabin, the engine began to lose power, then seized. The pilot said the "high sink rate and the headwind caused [him] to fall short of the runway by 200 yards." The airplane clipped a high stack of PVC pipes and impacted the ground inverted.

According to the FAA inspector who examined the airplane, the pilot had "removed the engine oil pressure sending unit from the engine oil pressure port, located on the right side of the engine-driven oil pump housing. He then installed a common automotive brass T-fitting, to which he attached both the oil pressure sending unit and a Hobbs hour meter fluid pressure-activated switch. The T-fitting failed in the pipe thread, flush with the pump housing exterior surface. The arm of the 'sending unit assembly' was about 4.5 inches, with an estimated weight of about 7 ounces. The path of the engine cooling air directed the leaking oil to the cabin air heat muff, where it was burned by the muffler prior to entering the cabin, accounting for the smoke in the cabin."