Primary finding
Probable cause
Failure of the pilot to adequately detect water contamination in the airplane's fuel system during preflight.
Investigator assessment
Analysis narrative
The pilot was conducting a maintenance test flight following an annual inspection and replacement of two cylinders. Shortly after takeoff the engine lost power. A forced landing was made to a highway and the airplane collided with 2 moving motor vehicles. Examination of the engine revealed evidence of water in the cylinders. The airplane had been sitting for several months without the fuel tanks topped off.
Source record
Factual narrative
-