Many in the recreational boating public are not aware of a serious type of accident that is neither rare nor without serious consequences. In these incidents the large outboard engine on a fast-moving boat strikes an underwater or floating object, breaks off the boat and flips into the passenger area while still running. The potential for disaster is obvious.
The art of positioning a propeller underneath a boat hull is not a new one. Designers and naval architects have been grappling with every aspect of the propulsion-by-propeller problem for generations, and the result has been the evolution of a well known set of standard and efficient solutions