Abstract: A minimum drag fluid reaction element including a rotatable shaft adapted to be supported by a vessel carried upon or within a fluid medium; and a rigid fluid reaction fin fixedly attached to the shaft for extension into the fluid medium, the shaft and the fin extending in opposite directions from a common intersection and forming an angle other than a right angle therebetween; the axis of rotation of the shaft lying in a plane generally normal to the fin whereby rotation of the shaft moves the fin through a path describing a right conical section. The angle between the fin and the shaft is preferably obtuse and the plane containing the axis of rotation of the shaft peripherally bisects the fin.