Designed and engineered by world class naval architect David Hubbard, the WingSail is the heart of the Harbor Wing AUSV's design and capability. Standing either thirty or sixty feet high, the environmentally friendly "engine" incorporates a number of unique elements. The rigid WingSail rotates 360 degrees enabling the vessel to be propelled in virtually any direction and maneuver efficiently upwind and downwind. Unique horizontally mounted airfoil "tails" control the direction of thrust and amount of "lift" that the WingSail produces. Directed by Harbor Wing propriety software, the WingSail provides high-end propulsion power that is elegantly and precisely controlled.