Event Details
A pilot reported that the airplane was fully serviced with fuel prior to departure, containing 130 gallons of usable fuel. The pilot had planned for a fuel consumption of 25 gallons per hour based on manufacturer data, which would have provided a one-hour fuel reserve. During the flight, the aircraft encountered forecasted turbulence. While descending, both engines stopped abruptly, according to the pilot, who described the event as "like fuel starvation."
The pilot maneuvered the airplane toward a highway for a forced landing but, due to traffic, selected a railroad right-of-way instead. During the wheels-up landing, the right wingtip collided with a boulder. This impact compromised the right wing auxiliary fuel tank and caused the fuel line to separate from the right tip (main) tank. No physical evidence of fuel was found at the accident site.
Aircraft and Fuel System Examination
Post-accident inspection revealed approximately one pint of fuel remaining in the right main tank; the left main tank was empty. Both fuel selectors were set to the main tank positions. During ground test runs, the left engine rotated but was not run due to a fuel leak at an 'O' ring on the throttle body. The right engine would only operate when an external fuel boost pump was turned on. An 'O' ring fuel leak was observed at the engine fuel pump, which also exhibited a fuel stain indicating seepage.
Further testing showed that after replacing the 'O' ring, the fuel pump and metering unit flowed within specifications. Both units appeared to be leaking, with deteriorated rubber components that were in need of overhaul. The time since the last annual inspection was 21 flight hours.