N984WB

On September 16, 1996, about 0645 central daylight time, a Piper PA-22-108, N984WB, registered to a private individual, experienced a total loss of engine power shortly after takeoff from the Ferguson Airport, Pensacola, Florida. Visual meteorological conditions prevailed at the time and a VFR flight plan was filed for the 14 CFR Part 91 personal flight. The airplane was substantially damaged and the airline transport-rated pilot, the sole occupant, sustained minor injuries. The flight originated about 3 minutes earlier.

The pilot stated that during the preflight of the airplane which he knew had not flown in about 10 days, he obtained two samples from each wing tank and three samples from the strainer. The only contaminant noted was four pinhead size droplets of water during the first sample from the strainer. He obtained two additional samples from the strainer and these were free of contaminant. He then started the engine and performed an engine run-up before departure with no discrepancies noted. He initiated the takeoff roll and when the flight was about 150-200 feet above the ground about 3/4 down the runway, the engine started sputtering and lost power. He then initiated a descent and the airplane collided with trees. The airplane came to rest upright and he was rescued and treated for his injuries.

The airplane was recovered and examination of the contents of the carburetor bowl revealed fuel and water. The carburetor was removed and partially disassembled for further examination which revealed that the carburetor bowl contained rust like contaminant. The economizer jet and the mixture control boss were plugged with debris. The nozzle assembly was partially plugged by debris. The carburetor was reassembled and placed on a test bench which revealed that the fuel flow pounds per minute at idle was only 44 percent of the minimum specified by the manufacturer. The fuel flow pounds per minute at just above idle, at about 1/2 throttle, at slightly greater than 1/2 throttle, and at full throttle were only 21, 53, 84, and 82 percents respectively of the minimum fuel flow required by the engine manufacturer.

Review of the engine logbook dated from March 6, 1962, the first entry, revealed no entry to indicate that the carburetor or engine have ever been overhauled or replaced. The carburetor was manufactured on February 14, 1961. A service bulletin (non-mandatory compliance) prepared by the Precision Airmotive Corporation, a FAA-PMA facility, indicates that specifically manufactured float type carburetors are to be overhauled whenever the engine is overhauled or 10 years since placed in service.

The engine was last inspected in accordance with a 100-hour inspection on March 1, 1996, at a tachometer time of 1,811.91. The previous engine inspection occurred on March 16, 1994, at a tachometer time of 1,801.80. The next previous inspection was on January 2, 1993, at a tachometer time of 1,756.88 hours. The engine had only been operated for about 438.34 hours from February 2, 1978, to the accident.