• The craft is force-balanced. It does not heel and wind induced loads can not cause it to capsize.
  • The craft utilizes only one sail at any given time thus reducing complexity and crew requirements for sail handling.
  • The sail is a jib having a high lift/drag ratio because there is no airflow disturbance on the low-pressure (leeward) side from a mast in front of the sail's leading edge.
  • The sail does not need sewn-in compound curvature thereby eliminating the cost of specialized expertise to make it.
  • The design provides an increase in the L/D ratio of the sail by sealing the gap between the sail's lower edge (the sail's foot) and the deck thereby providing an endplate effect that eliminates the induced drag created at the foot of the sail.
  • The outrigger hull's form on its leeward side and the sail's shape at its foot combine to create one continuous surface. This lowers the center of lift of the sail enabling closer spacing of the hulls and/or a more vertical position of the mast.
  • The inclined position and forward location of the sail provides a vertical component of the total lift force that acts to raise the bow of the outrigger hull.
  • The design yields a sailing vessel that moves through the water along the longitudinal axis of the hulls thus avoiding the drag associated with sideways movement of the hulls (leeway).
  • The design provides a sailing craft that will steer itself on a designated course with respect to the relative wind without steering inputs by the helmsman.
  • The dual keel/rudders at the bow and stern yield a design that is very maneuverable.
  • Retractable keel/rudders produce a deep draft, ocean-going vessel that is able to travel into shallow water or up to a beach for loading or unloading and for maintenance or repair.
  • Downwind sailing using the working staysail is readily accomplished by moving and attaching the sail's aft tack to the bow of the main hull.
  • Unlike a sailboat that heels over, there is no 'give' in strong winds or when a gust is encountered; rather the craft just goes faster. As the sail, rigging and mast take the full force of the wind, they (and the outrigger hull) must be very stiff and strong.
  • The sail obstructs visibility at the steering station from about 50 to 100 degrees off the leeward bow.
  • Two steering wheels are needed to provide optimal adjustment of the keel/rudders.

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© copyright Timothy Kingman 2005