The present invention relates to contour line technique for ship body. In the range of 1.5 to 6 station, the longitudinal section of streamlined ship body with W-type tunnel body possesses W-type contous line using double-sealed double tunnels in which a propeller is located. The disadvantages from tail tunnel type ship are overcome by means of the present invention which may provide greater turning force arm, raise the maneuverability, stability and safety of ship, and thereby the propelling force may be fully utilized. The velocity of ship may be extremely raised under the condition of constant motive force. It is applicable to super-swallow-water ship for inland river and swift current section of various river course. It is also applicable to high-speed navigation in swallow water. |