FACTOID # 21: 15% of Army recruits from South Dakota are Native American, which is roughly the same percentage for female Army recruits in the state.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Jetboat" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Jetboat
A rider on a Yamaha Waverunner XL performing a high-speed turn
A rider on a Yamaha Waverunner XL performing a high-speed turn

A jetboat is a boat propelled by a jet of water ejected from the back of the craft. Unlike a powerboat or motorboat that uses a propeller in the water behind the boat, a jetboat draws the water from under the boat into a pump-jet inside the boat, then expels it through a nozzle at the stern. Image File history File links Download high resolution version (2192x1574, 1837 KB)Pump jet driven PWC during a high-speed turn. ... Image File history File links Download high resolution version (2192x1574, 1837 KB)Pump jet driven PWC during a high-speed turn. ... Yamaha Motor Corporation (ヤマハ発動機株式会社) is a motorized vehicle-producing company, initially part of the Yamaha Corporation. ... A boat is a craft or vessel designed to float on, and provide transport over, water. ... Categories: Stub | Boat types ... A 1962 Rebel. A wooden speedboat with an outboard engine. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Categories: Marine propulsion | Stub ... Aft of the Soleil Royal, by Jean Bérain the Elder. ...


Jetboats were originally designed by Sir William Hamilton (who invented the waterjet in 1954) for operation in the fast-flowing and shallow rivers of New Zealand, specifically to overcome the problem of propellers striking rocks in such waters, although Italian inventor Secondo Campini had demonstrated a similar vessel as early as 1931 in Venice. Sir Charles William Feilden Hamilton (July 26, 1899 _ March 30, 1978), commonly known as Bill Hamilton, was a New Zealander who developed the modern jetboat. ... 1954 (MCMLIV) was a common year starting on Friday of the Gregorian calendar. ... Secondo Campini (born August 28, 1904 in Bologna, died February 7, 1980 in Milan) was an Italian engineer and one of the pioneers of the jet engine. ... 1931 (MCMXXXI) was a common year starting on Thursday (link is to a full 1931 calendar). ... Venice (Italian: Venezia, Venetian: Venezsia) is the capital of region Veneto, and has a population of 271,663 (census estimate January 1, 2004). ...


The difference between Campini's and Hamilton's inventions is that Campini's waterjet had a very short lifetime in operation due to some unsolved material problems. Hamilton, unlike Campini, filed for a patent. A patent is a set of exclusive rights granted by a state to a patentee (the inventor or assignee) for a fixed period of time in exchange for the regulated, public disclosure of certain details of a device, method, process or composition of matter (substance) (known as an invention) which...


Jet boats are highly maneuverable, and many can, from full speed, be reversed and brought to a stop within their own length, in a maneuver known as a Hamilton turn.


There is no engineering limit to the size of jet boats, though the classic prop-drive is more economical than the jet-drive. Thus, the biggest jet-driven vessels are found in military use. South Africa's Valour class frigates (approximately 120m long) are the biggest jet-propelled vessels so far. Even these German-built vessels are capable of performing the Hamilton turn. The South African Valour class frigates are the major surface ships of the South African Navy. ...

Contents

How jet boats work

A conventional screw impeller accelerates a large volume of water by a small amount, 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. A Pratt and Whitney turbofan engine for the F-15 Eagle is tested at Robins Air Force Base, Georgia, USA. The tunnel behind the engine muffles noise and allows exhaust to escape. ... Sir Isaac Newton, (4 January 1643 – 31 March 1727) [ OS: 25 December 1642 – 20 March 1727][1] was an English physicist, mathematician, astronomer, natural philosopher, and alchemist, regarded by many as the greatest figure in the history of science. ... Newtons First and Second laws, in Latin, from the original 1687 edition of the Principia Mathematica. ...


In a jetboat, pumping a small volume of water and accelerating it by a large amount delivers the thrust. The acceleration of the water is achieved by using multiple impeller stages. Steering is accomplished by small vanes that direct the water jet. An impeller is a rotor inside a tube or conduit to increase the pressure and flow of a fluid. ...


Unlike hydrofoils, which use underwater wings or struts to lift the vessel clear of the water, jetboats normally plane across the water surface, with only the rear portion of the hull displacing any water. With the majority of the hull clear of the water, there is reduced drag, greatly enhancing speed and maneuverability, so jetboats are normally operated at planing speed. Any slower, the jetboat loses most of its maneuverability and quickly slows down even more due to greatly increased drag. For this reason a jetboat is difficult to operate at speeds other than very fast or dead slow. For stability, the jetboat has a very shallow-angled (but not flat-bottomed) hull. At speed, jetboats can be safely operated in less than 12 inches (30 cm) of water. The Jetfoil Toppi is a ferry which connects Yakushima, Tanegashima Island and Kagoshima port in Japan. ... A Laughing Gull with its wings extended in a gull wing profile Aircraft wing planform shapes: a swept wing KC-10 Extender (top) refuels a trapezoid-wing F/A-22 Raptor A wing is a surface used to produce lift and therefore flight, for travel in the air or another... Planing has several meanings: With boats, planing or hydroplaning is a method by which a hull skims over the surface of the water, rather than plowing through it. ...


The jet of water is expelled above the water line, contrary to many people's intuition. Hamilton discovered early on that this greatly improved performance, compared to expelling below the waterline. From a physical point of view, this is understandable because it is the momentum of the expelled jet which provides the equal and opposite thrust. By expelling below the waterline, the momentum is rapidly absorbed by the surrounding stationary water; the jet does not "push against" the surrounding water. In classical mechanics, momentum (pl. ...


Queenstown, New Zealand, where jetboats are used extensively for adventure tourism, claims to be the jetboat capital of the world. Queenstown is a resort town in Otago in the south-west of New Zealands South Island. ... Adventure tourism is a type of niche tourism involving exploration or travel to remote areas, where the traveler should expect the unexpected. ...


Manufacturers

  • 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.
  • Sword Marine
  • Bombardier of Canada makes many models of both jetboats and jetskis.

Cabora builds light weight high powered jetdrive inflatables also know as BlowBoats. logo Bombardier Inc. ...


Applications

Applications for jetboats include adventure tourism, surf rescue, farming, fishing and marine law enforcement, exploration, pleasure boating and other water activities where a motor boats are used. Jetboats can also be raced for sport, both on rivers and on specially designed racecourses. Many jetboats are small enough to be carried on a trailer and towed by car. Recently there has been increasing use of jetboats in the form of rigid-hulled inflatable boats and as luxury yacht tenders. Severn class lifeboat in Poole Harbour, Dorset, England. ... Farming, ploughing rice paddy, in Indonesia Agriculture is the process of producing food, feed, fiber and other desired products by cultivation of certain plants and the raising of domesticated animals (livestock). ... Fishing is the activity of hunting for fish by hooking, trapping, or gathering animals not classifiable as insects which breathe in water or pass their lives in water. ... Exploration is the act of searching or traveling for the purpose of discovery, e. ... // A rigid-inflatable boat (RIB) or rigid-hulled inflatable boat, (RHIB) is a light-weight but high performance and high capacity boat constructed with a solid, shaped hull and flexible tubes at the gunwale. ... A luxury yacht tender is used to service and to provide support and entertainment to a private or charter luxury yacht. ...


One very important feature of the Jet boat is the fact that it has no external rotating parts, it is essentially safe for swimmers and marine life, excluding being clobbered by the hull. This in itself can be reason enough to use this type of propulsion.


See also

Pump-jet PWCs such as this Yamaha Waverunner are extremely popular for their speed and maneuverability. ... Jet Sprint Boat racing is a form of racing sport where trailerable speed boats, powered by water jet propulsion rather than by conventional propellers, race around shallow, artificial watercourses characterised by many tight turns. ...

External links


  Results from FactBites:
 
NationMaster - Encyclopedia: Jetboat (1580 words)
Unlike a powerboat or motorboat that uses a propeller in the water behind the boat, a jetboat draws the water from under the boat into a pump-jet inside the boat, then expels it through a nozzle at the stern.
Jetboats were originally designed by Sir William Hamilton (who invented the waterjet in 1954) for operation in the fast-flowing and shallow rivers of New Zealand, specifically to overcome the problem of propellers striking rocks in such waters, although Italian inventor Secondo Campini had demonstrated a similar vessel as early as 1931 in Venice.
Queenstown, New Zealand, where jetboats are used extensively for adventure tourism, claims to be the jetboat capital of the world.
Cariboo Chilcotin Jetboat Adventures, British Columbia, Canada. Jetboat tours on BC's Fraser River, Chilcotin River, ... (767 words)
Combine your Jetboat Tour with a 4x4 Van Tour or a Native Cultural Tour and truly experience our corner of the world.
When we are at camp we can easily get into our jetboat and cross the water to explore the other side or find fishing spots etc.
We don't have to wear wet suits that can be restricting and sweaty on a hot day this allows us to wear our more comfortable clothes while out on the river.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m