Primary finding
Probable cause
The pilot’s did not properly secure the airplane prior to rotating the propeller by hand, resulting in inadvertent movement of the airplane and collision with a building.
Investigator assessment
Analysis narrative
The pilot reported that he could not start the airplane's engine using the electric starter, so he elected to turn the propeller by hand to start the engine (hand-propping). He stated that when the engine started, the airplane's parking brake did not hold and that the airplane began to roll. He was unable to open the door to reduce the throttle setting, and the airplane subsequently struck a building. The airplane sustained substantial damage to the left wing, the fuselage structure near the firewall, and the engine mount structure.
Source record
Factual narrative
The pilot reported that he could not start the airplane's engine using the electric starter. He elected to hand start the airplane. He stated that when the engine started, the airplane's parking brake did not hold and the airplane began to roll. He was unable to open the door to reduce the throttle setting. The airplane subsequently struck a building. The airplane sustained substantial damage to the left wing, the fuselage structure near the firewall, and the engine mount structure.