| 摘要 |
PURPOSE:To eliminate a rudder plate protruded from a ship boat bottom and to improve safety by a method wherein a bow part is vertically rocked along with longitudinal movement of a handle unit mounted to the front part of a ship hull to cause the ship hull to skid and cruise underwater by means of jet propulsion. CONSTITUTION:A handle unit 14 is longitudinally movably mounted on the top surface of an expansion part 6 formed to the front half part of a ship hull 1. When the handle unit is moved to a frontmost end, a center of gravity G of the whole of the ship hull 1 is displaced to a position located further in front than the center of buoyancy F togetherwith a rider 24, a bow is lowered, and the tip part of a gunnel part 2 is sunk in water. When, with this state, a small marine vehicle sails forward, a water resistance force exerted on the whole of a bow part is exerted in a rear lower direction, and during given slow acceleration, the whole of the ship hull 1 is gradually sunk in water for cruise underwater. In this case, water scooped up by means of the bow part is caused to flow through a recessed groove 5 to a footrest part 7 to promote submergence. During cruising underwater, air necessary to an engine is introduced to an engine room through an air introduction port 23 protruded from a water surface at the upper end of an air funnel 22. |
