Personal water craft

Before 1990, personal water craft emissions were unregulated in the United States. Many were powered by two-stroke cycle engines, which are smaller and lighter than four-stroke cycle engines but much more polluting. Simple two-stroke engines are lubricated on a "total loss" method, mixing lubricating oil with their fuel; they are estimated to exhaust in excess of 25% of their fuel and oil unburned, in addition to t ...

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Personal water craft, Personal water craft - Non-recreational uses, Personal water craft - Emissions, Personal water craft - List of popular brands

Read more here: » Personal water craft: Encyclopedia II - Personal water craft - Emissions

A pump-jet or water jet is a marine propulsion system that creates a jet of water for impulse. The mechanical arrangement may be a ducted propeller with nozzle, or a centrifugal pump and nozzle. Pump jets have some advantages over bare propellers for certain applications; higher power density (with respect to volume) and ultra-quiet designs for submarines, the Trafalgar class is an example. They protect the rotating element ...

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A conventional screw propeller accelerates a large volume of water by a small amount, in a manner similar to the way an aeroplane's propeller accelerates a large volume of air by a small amount. An aircraft's jet engine, by contrast, accelerates a small volume of air by a large amount. Both methods yield thrust due to Newton's third law — every force gives rise to an equal and opposite force. In a jetboat, by pumping a small volume of water and accelerating it by a large amount, useful thrust can be obtained. This is achieved using ...

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Jetboat, Jetboat - How jet boats work, Jetboat - Manufacturers, Jetboat - Applications

Read more here: » Jetboat: Encyclopedia II - Jetboat - How jet boats work

Applications for jetboats include adventure tourism, surf rescue, farming, fishing and marine law enforcement, exploration, pleasure boating and other water activities where a motor boat is used. Jetboats can also be raced for sport, both on rivers and on specially designed racecourses. Most jetboats are small enough to be carried on a trailer and towed by car. Queenstown, New Zealand claims the title of jetboat capital of the world. Also, Bombardier of Canada makes m ...

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Jetboat, Jetboat - How jet boats work, Jetboat - Manufacturers, Jetboat - Applications

Read more here: » Jetboat: Encyclopedia II - Jetboat - Applications

The New Zealand company Hamilton Jet designs and builds jetboats and manufactures the Hamilton Jet Unit, the patented device that produces and controls the water jet. Jet boats are normally powered by a V8 petrol engine, often an adapted automotive engine from a high performance car manufacturer. JetPac™ Sword Marine ...

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Jetboat, Jetboat - How jet boats work, Jetboat - Manufacturers, Jetboat - Applications

Read more here: » Jetboat: Encyclopedia II - Jetboat - Manufacturers

Although most personal water craft are purchased by individuals for recreational use, they are also used for more serious purposes. Personal water craft are small, easily handled, fairly easy to use, affordable, and their propulsion systems, which do not have external propellers, are safer for swimmers and wildlife. For these reasons, they are sometimes used in preference to small motorboats. Lifeguards in some areas use personal watercraft to rescue water users who get into difficulties, equipped with rescue platforms to carry people back to shore. Personal ...

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Personal water craft, Personal water craft - Non-recreational uses, Personal water craft - Emissions, Personal water craft - List of popular brands

Read more here: » Personal water craft: Encyclopedia II - Personal water craft - Non-recreational uses