What happened
While maneuvering for an aerial application run at approximately 100 feet above ground level, the pilot reported that the airplane began to sink. Despite adding power, the engine failed to respond. The pilot attempted to avoid various obstructions, but the aircraft subsequently struck a fence and crashed into a cultivated area. The accident occurred roughly 10 minutes after takeoff. The pilot had departed with full fuel.
Witnesses at the scene reported hearing the engine make noises described as sputtering, backfiring, and cutting in and out during the flight.
The investigation
A postaccident examination of the aircraft showed little to no damage to the three propeller blades. Investigators found fuel remaining in one of the two interconnected main tanks at the crash site; however, the other main tank was empty. It was noted that the wing containing the empty tank had sustained substantial damage.
During a postaccident test run, the engine operated successfully with normal turbocharger operation and normal fuel pressure, provided the electric boost pump was primed first. Once the boost pump was turned off, the engine continued to operate normally using the engine-driven fuel pump.