Abstract: An improved boat construction is disclosed in which a boat, having the typical elongated hull, bow and stern, has a bottom configured as a hydroplane including a transverse step spaced from the bow and stern. A well is provided in the boat bottom and extends from at least the transverse step through the boat stern and receives a powered impeller for engaging and pushing water backwards in a confined flow path within and beyond the well so as to thrust the boat forward. Vertical deflectors are positioned rearwardly of the powered impeller and are attached to the boat in the vicinity of the boat stern for engaging the backwardly moving water in the confined flow path so as to increase or decrease the size of the confined flow path of backwardly moving water emanating from the powered impeller. Immediately forward of the powered impeller in the well is a horizontal deflector which directs more or less water to the powered impeller.