A watercraft vessel with at least one planing hull, in the form of a single unitary hull or with two or more interconnected hulls, each hull having at its bottom portion a deadrise angle in the interval 5°-70° and provided with at least one water-deflecting surface which extends rearwardly and outwardly in relation to a keel region and which is oriented and configured so as to create a lifting force, and also a forward thrust on the hull. The forward thrust is caused by a lateral spray water stream, which is redirected rearwardly by the water-deflecting surface. The latter should be located laterally outwardly of but adjacent to an approximately triangular bottom part which is submerged at the planing speed. The hull will also provide a smoother ride than conventional, planing hulls, especially in heavy sea.