This March 2008 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: Cessna 172. Injuries: None. Location: Charlottesville, Va. Aircraft damage: Substantial.
What reportedly happened: The pilot attempted to start the engine using the key, but was unsuccessful, so he decided to attempt to hand-prop the airplane to get the engine started. There was no one in the cockpit at the controls. As he hand-rotated the propeller, the engine started, and the airplane began to roll forward. It continued across the ramp and hit two other airplanes before it came to a stop.
Probable cause: The pilot’s improper engine starting procedures.
For more information: NTSB.gov