WPR17LA011

The commercial pilot was conducting a local flight when the engine experienced a partial loss of power. The pilot stated that he switched the fuel selector from the right to the left tank, applied full throttle, set the mixture control to full rich, and extended the wing flaps. The engine seemed to continue running during the forced landing. The airplane impacted a stand of almond trees and came to rest in a nose-down attitude about 1 1/2 miles from the destination. The pilot reported no mechanical anomalies with the airplane that would have precluded normal operation and stated that there was enough fuel to get to the destination, "but not all in the tank that was being drawn from." A postaccident examination revealed that the right wing tank, which was undamaged, was void of any usable fuel; about 4 ounces of fuel was drained from the tank. Also, there was no evidence of a fuel leak from either wing tank. The fuel selector was observed positioned to draw fuel from the left tank, which contained about 7 gallons of fuel. Further examination revealed that the fuel control unit's inlet finger strainer was clean and free of obstructions. Additionally, the fuel supply line contained a small amount of clean, blue-colored fuel when disconnected. No water or particulate contaminates were detected in the fuel system. A postaccident engine run revealed no anomalies that would have precluded normal operation. The partial loss of engine power was likely due to the pilot's improper in-flight fuel management, which resulted in fuel starvation to the engine after all of the usable fuel in the right wing tank had been consumed.

On October 22, 2016, about 1800 Pacific daylight time, a Mooney M20J airplane, N201EU, was substantially damaged following a forced landing due to a partial loss of engine power near Coalinga, California. The private pilot, who was the registered owner of the airplane, and his sole passenger were not injured. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being operated in accordance with 14 Code of Federal Regulations Part 91, and a flight plan was not filed. The flight departed Hanford Municipal Airport (HJO), Hanford, California, about 1740, with a reported destination as Harris Ranch airstrip (3O8), located about 8 nautical miles (nm) northeast of Coalinga. In a report submitted to the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), the pilot reported that while on approach to 3O8 and about 8 nm [southeast] of the airstrip, the engine "hiccupped," then about 15 seconds later it began running rough and producing no power. The pilot stated that he then switched fuel tanks from the right tank to the left tank, and selected wide open throttle, mixture full rich, and added flaps to help with glide performance. In order to avoid high tension power lines, the pilot had to climb over them, which reduced both glide performance and airspeed. The airplane subsequently impacted a stand of almond trees, coming to rest in a nose down attitude on the ground. The pilot added that the engine appeared to be running until impact. Additionally, the pilot provided the following comment in the RECOMMENDATION section of the report: "We had enough fuel to get to our destination, but not all in the tank that was being drawn from. Better scan of the fuel flow would have helped prevent this accident." An onsite postaccident examination of the airplane, which was performed by Federal Aviation Administration (FAA) aviation safety inspectors on the morning following the accident, revealed that the airplane had come to rest in a tree orchard about one and one-half miles east of 3O8. A visual inspection revealed that there were no signs of fuel leakage on the ground, nor were there any fuel stains on the exterior surfaces of the airplane. The fuel system was observed to be completely intact and undamaged, with both wing tanks and strainer free of contaminates. The fuel selector was found pointed to the left tank position. Investigators reported that when the right wing tip was slightly raised, and the fuel selector positioned to the right tank position, about 4 ounces of clean blue colored gasoline was observed drained into a clean glass container. Subsequently, the left fuel tank sump was drained completely of its contents, which yielded about 7 gallons of clean blue colored gasoline; the flow divider contained a trace of gasoline. Further examination revealed that the fuel control unit's inlet finger strainer was observed to be clean, free flowing, and free of obstructions. Additionally, the fuelsupply line dribbled a spoonful of clean blue colored gasoline when disconnected. No water or particulate contaminates were detected in the fuel system. On November 3, 2016, under the supervision of the NTSB IIC and FAA inspectors, a test run of the engine was performed at the facilities of Valley Air Crafts, Tulare, California. The results of the test run revealed normal engine priming with the boost pump, normal starting, and normal operation when supplied with adequate fuel. Idle speed, idle mixture magneto checks and run up to maximum power were smooth and normal with an exemplar propeller installed. There were no anomalies detected with the engine that would have precluded normal operation.