The Aeronca 11AC was not equipped with an electrical system, so the engine was started by hand propping.
The pilot reported that he did not have a passenger to hold the brakes in the cockpit during engine start, nor did he use wheel chocks or tether the tail to a fixed object because he thought using the airplane’s parking brake would keep the airplane stationary after the engine had started.
Before the engine was hand propped, he set the throttle about ¼” to ½” forward of the idle position, but the engine’s speed was much higher than he expected after the engine started.
The unoccupied airplane initially moved forward before it entered a left turn on the ramp in front of a row of hangars at the airport in Wapakoneta, Ohio.
Although the pilot was able to reach into the cockpit to move the throttle to idle, the airplane continued in the left turn and hit a closed hangar door, resulting in substantial damage to the right wing.
Probable Cause: The pilot’s inadequate engine hand propping procedure resulting in the unoccupied airplane’s unintended movement and subsequent impact with a hangar.
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This July 2021 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.