NTSB Factual Report

The pilot stated that prior to starting the engine by manually rotating the propeller, he set the bakes, throttle, and trim. He exited the airplane, and proceeded to rotate the propeller. When the engine started, it went to full rpm and the airplane started to move forward on the taxiway at a high speed. The airplane veered off the taxiway and continued its high speed taxi until it impacted a hangar door, damaging the engine, both wings, and the right main landing gear. The pilot reported to the responding officer that he had not chocked the airplane and thought the brake was set. He further reported there were no mechanical problems with the airplane.

NTSB Probable Cause

The pilot did not properly secure the airplane before starting the engine by manually rotating the propeller, which resulted in the inadvertent movement of the airplane.