Abstract: Substantial improvements in design, cost, performance, safety and comfort could be had in sailboats if the hull were to navigate in a level attitude even under strong wind conditions. This is achieved by the present invention by virtue of the mast pivoting on the hull along a longitudinal axis of the vessel. In this way the wind pressure on the sail generates a forward component and a lateral component, the former being the useful wind force which the mast transmits through the pivot to the hull of the boat to propel it. The lateral component, which in conventional fixed-mast boats causes the hull to list depending on the wind direction and force, is not transmitted by the pivot to the hull but causes the part of the mast holding the sail to tilt leeward about the pivot.