Aviation accident SEA00LA089

The pilot's improper decision to attempt to close the canopy (entry door) after it inadvertently opened in flight, instead of making a precautionary landing with it open. Factors include the pilot's failure to follow all items on the checklist, his failure to fully secure the canopy/door prior to takeoff, the movement of the pilot's seat pan while in flight, the restriction of the control stick movement by the displaced seat pan, and the pilot/builders failure to adequately secure the seat pan to the airframe.