Abstract: A watercraft having at least a pair of steerable propellers thereon spaced longitudinally along the center of the watercraft from a center of lateral resistance on the watercraft. The steerable propellers are also spaced equidistant from the longitudinal center line and on opposite sides thereof. The propellers are rotatably supported in underwater housings supported for angular movement through 360.degree.. A control device is provided for varying the direction of applied thrust to the watercraft by systematically varying the axes of rotation of the propellers relative to each other, assuming the thrust force for each steerable propeller is of the same magnitude. The magnitude of thrust can be, if desired, varied to provide additional control variations for the watercraft.