ANC03LA039 · Cessna 207

The commercial certificated pilot was conducting a cross-country maintenance test flight following a recent engine overhaul. The airplane's engine was recently installed by company maintenance personnel, and the pilot was putting flight hours on the engine. During the flight, the engine oil pressure was indicating about 50 psi. The pilot made a slight change in the engine rpm and manifold pressure settings, and the oil pressure rose rapidly to the top of the operating range. The engine cylinder and oil temperature readings did not change. The engine then lost power. The pilot switched the fuel selector from the left tank to the right tank and activated the engine boost pump. Engine power was not restored, and he switched the selector back to the left tank. The pilot indicated the engine sounded as if it were firing on all cylinders, but only at an idle. The pilot also reported that, "I do not know whether the left fuel tank was completely exhausted of fuel or not. The engine went from power to idle immediately, without any sputtering or coughing." During a forced landing, the airplane collided with trees. An FAA inspector traveled to the accident scene and examined the airplane. He reported that the left fuel tank was empty. The right fuel tank contained about 15 gallons of fuel. He found no evidence of fuel leaking, and the engine and propeller controls were properly attached. The inspector started the engine, but due to broken engine mounts, the engine was not operated above an idle, however throttle movement was applied enough to elicit an increase in rpm. The FAA inspector also reported that the operator sent the engine to a maintenance facility where it operated at full power on an engine test stand.

Verbatim NTSB analysis and probable cause from the NTSB dataset