Accident Sequence
The flight was intended to proceed to a nearby airport for refueling before a longer flight. The pilot in command (PIC), a commercial-rated pilot and owner, occupied the right front seat. A private pilot was in the left front seat, and a student pilot was in the rear seat.
After engine start, the after-market, panel-mounted fuel management system indicated 235 pounds of fuel remaining. The left main fuel tank gauge showed approximately 15 gallons (top of the yellow arc), while the right main fuel tank gauge indicated near empty (bottom of the yellow arc). No operating restriction prohibited operation in that fuel configuration. Believing adequate fuel was available, the PIC departed for the estimated flight of ten minutes or less.
Following departure, the aircraft climbed and turned right, then leveled off at approximately 2,000 feet above terrain. Shortly afterward, the right fuel tank "Fuel Low" light illuminated. About one minute later, the engine lost power. The PIC was unable to restart the engine and executed a forced landing in a wheat field located among hilly terrain. Power lines at the approach end of the field prevented touchdown until the aircraft was past the halfway point. Although the landing was successful, the aircraft could not be stopped before exiting the far end and rolling into a deep ravine.
Post-Accident Findings
Inspections of the airframe and an engine test run revealed no system malfunctions. A post-accident review determined that the aircraft's fuel system had undergone a significant modification during a major alteration that was not approved by the Federal Aviation Administration (FAA). As part of this alteration, the routing of excess fuel from the header tank was substantially lengthened. No approved flight tests were conducted to verify adequate fuel supply to the engine under all attitudes, power settings, fuel loads, and fuel distributions.
Additionally, during installation of the after-market fuel management system by an avionics shop, an incorrect calibration factor was entered into the unit. This error caused the displayed fuel usage to be approximately 9 percent less than the actual amount consumed.
With an unaltered fuel system, the aircraft would have arrived at the destination with about 11 minutes of fuel remaining. Because no amendments were made to the Pilot's Operating Manual regarding the modification, the pilot had no indication that the engine would lose power during the flight.