Abstract: A swimming frame for competition in swimming, swimming instruction, muscle strengthening, and entertainment in the water comprises a pair of floats (1), a clamping unit (2, 3), and a paddle unit (4, 5, 6). It might be used by everyone regardless of the ability to swim. The paddle unit might by modified giving an additional possibility to practice butterfly-like and crawl-like style of swimming. A swimmer being clamped between rigid (2) and flexible (3) portion of the clamping unit is producing the push-pull movements of the paddle unit. When he pushes the unit, the paddle (4) is rotated up to horizontal position by the water pressure against its front. When he pulls the unit, the paddle is rotated up to vertical position by water pressure against its back. Because of the difference in the paddle hydroresistance between push and pull movements the swimming frame will be propelled by the swimmer.

Abstract: A boat comprising a tube-like hull (1), a hydrofoil (2) fixed to its front portion, a pair of wings (4) hinged to each side of its rear portion, a fin (20) fixed to its rear bottom portion, an out-board-type motor (9) provided in its center of gravity, and a steering lever (14) that can be rotated and also tilted. Rotation of the lever (14) causing rotation of the motor (9) and steering the boat. Tilting the lever causing lifting or lowering the wings (4). Each wing (4) has a float (5) fixed to its end. When the boat stops and at low speed the floats are in the water. When the boat at high speed an operator gives lift to the floats out of the water. At highest speed an operator puts the wings in parallel with the water surface and a ground effect is used. Central location of the motor contributes the boat to go into hydroplaning at low speed and gives lift to the rear portion of the boat using water pressure created by a propeller. The most controlable boating and efficient usage of motor power are provided.