Project's synopsis

From its apparition the water-jet propeller has had the limitation of having its maximum output only at a very determined number of turns corresponding to those  which the nozzle is designed for, in relation to the power available and the speed of the boat. Going away from this condition the yield decade a lot quickly and a lot more regarding the traditional propeller. this has strongly limited the spread of this propeller. The scope of the patent is to be able to regulate the section of the nozzle in relation to the capacity of the pump and this is obtained in a simple and much economic way by expandible equipments used in the nozzle itself. The fuctioning of the system, in accordance to the the variations of the engine's speed, both in increase and decrease, regulated by the pilot, allows to maintain an almost constant speed of expulsion of the water in an interval of turns that nearly covers completely the engine's power allocation. After all therefore, a high propulsive yield is obtained nearly in all the engine's power capability. Today the availability of materials with characteristics of resistance and high flexibility can, with simple tests experiences, allow the achievement of this project's purposes, carrying to a more wide spread of water-jet propellers.