This August 2007 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Aircraft: Beechcraft Duke.
Location: Bismarck, N.D.
Injuries: None.
Aircraft damage: Substantial.
What reportedly happened: Prior to arriving at the airport, the pilot called the FBO and asked to have his airplane out and to add 30 gallons of fuel to each tank. When the pilot arrived at the airport, the airplane had already been fueled. He performed a pre-flight inspection, which included visual checks of the fuel. The fuel was blue, consistent with 100LL aviation gasoline. The pilot reported that the start-up, taxi and pre-takeoff checks were normal,so he proceeded to takeoff. At about 32 inches of manifold pressure, the left engine stumbled and he aborted the takeoff. He returned to the run-up area and attempted to troubleshoot the problem, then performed another run-up. The run-up was normal so he attempted another takeoff, which again resulted in an aborted takeoff.
He then returned to the maintenance area where a mechanic boarded the airplane and a full power run-up was performed. No anomalies were noted. After the mechanic deplaned, the pilot returned to the runway and was again cleared for takeoff. He entered the runway, held his brakes, and increased the power to 35 inches of manifold pressure. He checked the engine gauges and all were normal so he applied full power and proceeded to takeoff. After liftoff, he noticed a fluctuation in the right engine’s manifold pressure and he began a gradual left turn. The left engine’s power then began to fluctuate. Attempts to rectify the power fluctuations were unsuccessful and he initiated an off-airport landing in a residential area.
During the post-accident investigation, a fuel receipt revealed the airplane had been improperly fueled with aviation jet fuel.
Probable cause: The improper fueling of the airplane by the FBO, which led to the loss of power of both engines.
