Water-jet propulsion has many advantages over 'conventional' complexes with a propeller, but nevertheless they have yet to gain popularity among fans of water recreation. The following well-known writer and marine Dag Pike journalist tries to understand why some water-jet propulsion katerostroiteli use, while others ignore them, and answer the question – whether the water cannons on the market prospects for pleasure boats? In use modern water-jet propulsion much really unusual. The strangeness is that today they are used exclusively in two like the opposite – 'polar' – areas of shipbuilding. It is either multi-shaft installation of high power water-jet on a giant high-speed ferries. Or is it a water cannon at the smallest high-speed machines – jet-, and for them it is the only way an engine.
All the same basic the market for recreational motor boats are still a boat and motor boats with propellers. (Let's not talk about a very small number of outboard engines, manufactured with water cannons.) For the uninitiated, a water jet propeller is just the same prop, but enclosed in a tube, but in reality it is one of the most difficult types of propulsion systems. Water cannon above all – a pump that sucks water through the inlet hole, it accelerates and pushes out through the nozzle. The nozzle can be rotated in the horizontal plane, providing a rotation of the vessel and a nozzle shut-off baffle can turn back the stream of water that will ship reverse. In the water cannons are quite large losses due to friction as the water flows inside the pipe, but this disadvantage is compensated by high efficiency pump impeller – impeller, the impeller water jet.