Abstract: A method and apparatus is directed towards an advanced blade section for propellers that allow watercrafts to effectively travel in both sub-cavitating and super-cavitating modes. The advanced blade section includes a streamlined profile having a convex upper surface and a lower surface that includes both a convex portion and a concave portion. When the propellers are rotated in a first direction at low speeds to propel the watercraft in the forward direction, the advanced blade section experiences a fully wetted flow over both the upper and lower surfaces at low speeds. At high speeds, the advanced blade section experiences a partially wetted flow, with only a front part of the lower surface being fully wetted, at high speeds. When the propellers are rotated in a second direction opposite the first direction to reduce the speed of the watercraft, the blade section experiences a substantially wetted flow over both upper and lower surfaces.

Abstract: A magnetostrictive rod subject to a magnetic field generated by an electrical activating coil within a pocket of a propeller blade is held in abutment with the body of the blade to effect its deflection causing change in shape involving a variation in blade camber in accordance with electrically powered adjustment control.