Piper PA 28-140 N3976K accident near Muskogee, Oklahoma

Probable cause

The pilot's improper in-flight fuel management, which resulted in a partial loss of engine power due to fuel starvation.

NTSB analysis

The private pilot was conducting a local area flight when the airplane experienced a partial loss of engine power. The pilot stated that he applied carburetor heat, switched fuel tanks (from left to right), activated the electric fuel pump, and verified magneto operation; however, despite his corrective actions, the engine continued to operate at 500 rpm. He chose to make a forced landing on a nearby highway. The pilot reported that, shortly before the landing flare, the left wing struck a road sign, and the airplane swerved left into the grass median.

A postaccident examination revealed that the left wing fuel tank did not contain any usable fuel; less than 1 quart of fuel was drained from the tank. A visual inspection of the left wing fuel tank revealed that it was intact and appeared undamaged. Further, there was no evidence of a fuel leak from either wing tank. The fuel selector was found positioned to draw fuel from the right fuel tank, which contained about 10 gallons of fuel. The fuel samples collected from each wing tank did not contain any water or particulates. The fuel supply line located between the engine-driven fuel pump and the carburetor did not contain any fuel, and the carburetor bowl contained residual fuel. The electric fuel pump functioned normally when tested after the accident. The partial loss of engine power was 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 left wing tank had been consumed.

Text from the NTSB. Open the NTSB docket for CEN17LA186 for the full record.