Flight Details
The pilot was in cruise flight at an altitude of 19,000 feet mean sea level (msl) for approximately 1 hour and 10 minutes on an easterly heading. He requested a diversion from his filed destination to an airport along his route to use a restroom. Two miles west of his amended destination at 12,000 ft msl, the pilot advised the controller of a “fuel emergency light” and requested an expedited approach. The controller acknowledged the low fuel warning and cleared the airplane to descend.
Instead of descending over the airport, the airplane continued eastward for nearly 8 miles before reversing course. After reversing, the pilot assumed a parallel reciprocal track and only turned toward the airport when the airplane intercepted the extended centerline of the landing runway. The pilot then reported being unable to reach the airport and performed a forced landing less than 1 mile from the runway.
Fuel System Examination
Both fuel tanks were breached during the accident sequence. Detailed postaccident inspections revealed no leaks in either the supply or return sides of the fuel system. A computer tomography scan and flow-testing of the engine-driven fuel pump showed no leaks or evidence of fuel leakage. The engine ran successfully in a test cell.
Data Analysis
Data from an engine and fuel monitoring system indicated that, during the two flights preceding the accident flight, the fuel quantity reduction was consistent with fuel consumption rates at respective power settings (climb, cruise, etc.). During the accident flight, the reduction in fuel quantity was consistent with indicated fuel flow throughout the climb. However, after engine power was reduced, the fuel quantity continued to decrease at a rate consistent with a climb power setting, while the fuel flow indicated a rate consistent with a cruise power setting. The data also showed that the indicated fuel quantity in the left and right tanks reached 0 gallons within about 10 minutes of each other, shortly before the accident.
Based on the available data and findings, the engine likely lost power due to exhaustion of the available fuel supply. However, the disparate rates of indicated fuel flow and fuel quantity reduction could not be explained.