Event Description
While operating in cruise flight, the engine experienced a partial loss of power. Although some power continued to be produced, it was insufficient to maintain level flight. In response, the pilot activated the fuel boost pump and selected a different fuel tank, but the condition did not improve. The pilot then proceeded to search for a suitable landing area. The only viable option identified was a golf course, but the aircraft came up short of its boundaries. As the pilot attempted to touch down on a street immediately outside the golf course, the airplane struck a pole.
Investigation Findings
A post-accident examination of the aircraft revealed a fuel system anomaly. Air was found to be leaking into the fuel system due to a worn fuel selector valve stem and a fuel selector valve O-ring that had become hardened and brittle. These conditions allowed air to enter the fuel supply, compromising engine performance.