What happened
The pilot entered the aircraft for a brief period before exiting and moving to the front of the plane. While standing at the nose, he pulled down on the propeller blades in an attempt to rotate the engine. The engine suddenly fired, causing the propeller to strike the pilot's head.
The investigation
A person who approached the aircraft shortly after the incident observed the cockpit interior. They noted that both magnetos were switched on and the master switch was engaged. Additionally, the engine controls were positioned fully forward, and the fuel selector was set to the right tank.
Findings
The sequence of events indicates that the engine started while the pilot was in a dangerous position near the propeller arc. The presence of power sources and fuel flow suggests the engine was ready to fire when the propeller was manually turned.