Abstract: A kayak paddle has blades configured to generate forward kayak momentum in each one of the three paddling movements, being more effective than known paddles, using its hydrodynamic profile to reduce formation of turbulent and eddy currents when moved in the water both, during insertion and retrieval. The paddle is characterized by a blade with a cross section in which both edges are curved, the frontal face is convex, and the back face is either flat, concave or both, but not convex, so as to benefit from the water flow around the surface or “Bernoulli Effect”, specifically on insertion in deep water and retrieval from it, producing forward motion of the kayak due to such hydrodynamic forces.

Abstract: A kayak paddle has blades configured to generate forward kayak momentum in each one of the three paddling movements, being more effective than known paddles, using its hydrodynamic profile to reduce formation of turbulent and eddy currents when moved in the water both, during insertion and retrieval. The paddle is characterized by a blade with a cross section in which both edges are curved, the frontal face is convex, and the back face is either flat, concave or both, but not convex, so as to benefit from the water flow around the surface or “Bernoulli Effect”, specifically on insertion in deep water and retrieval from it, producing forward motion of the kayak due to such hydrodynamic forces.

Abstract: A bicycle-type marine vessel including a long, narrow hull unstable in nature, that keeps balance on the water by means of a front rotating keel-propeller system that plays the role of a front wheel on a ground bicycle. The forward location of the keel and propeller permit the operator, sitting on a ground bike type frame, to balance and direct the vessel, while in motion, by means of the handlebar and body leaning. Forward impulse is achieved by leg actuated pedals that transmit power to the propeller placed at the back of the forward turning keel. The balancing force comes from the course change of the hull given by the new keel and propeller direction.