Abstract: A system for sailboats for the purpose of maintaining the trim or attitude of the hull in a level position and at the same time adjusting the rigging and keel. The mast is made so that it can tilt to port or starboard and apparatus is provided to produce a force or torque tending to urge the mast back to its upright position and to produce a righting moment on the hull. Alternative apparatus is provided to produce these forces. A rotatable keel is provided which is automatically adjusted when the mast tilts to compensate for the tendency of the craft to make leeway while under way. An auxiliary mast is provided, suspended from the top of the regular mast which is swung to port or starboard to keep the mainsail substantially upright. A horizontally movable jib boom is provided for the foresail and sheets are provided so that the helmsman can adjust the aspect of the foresail to keep it aligned with the mainsail when the mast tilts.

Abstract: Mast is pivoted to sailboat hull and carries a counter-balance weight below the pivot. Wind pressure causes mast heeling with the counter-balance supplying the mast-righting force. Additionally, movable weights in the hull bottom are cable-connected to the mast so that, upon mast heeling with respect to the hull, the weights are moved upward and outward. The underwater structure of the sailboat is also controlled by mast listing or heeling. When centerboard-equipped, the centerboard is lowered with mast heeling. When keel-equipped, the pivoted keel is swung for maximum stability.