Minehunters Of France
A minehunter is a naval vessel that seeks, detects, and destroys individual naval mines. Minesweepers, on the other hand, clear mined areas as a whole, without prior detection of mines. A vessel that combines both of these roles is known as a mine countermeasures vessel (MCMV). Description A minehunter uses an imaging sonar to detect and classify targets and then sends out divers or remotely operated vehicles to inspect and neutralise the threat, often using small charges that are detonated remotely. As minehunters will often be operating in close proximity to mines, they are designed so as to reduce their own acoustic and magnetic signatures, two common forms of trigger for mines. For example, they are often soundproofed by mounting machinery on shock absorbers or by using quiet electrical drive, low magnetic electric motors and usually have a wood, fiberglass or non-ferrous metal hull, or are degaussed to reduce magnetic signature.Design Guide and Requirements for Eq ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fiberglass
Fiberglass (American English) or fibreglass (Commonwealth English) is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass cloth. The plastic matrix may be a thermoset polymer matrix—most often based on thermosetting polymers such as epoxy, polyester resin, or vinyl ester resin—or a thermoplastic. Cheaper and more flexible than carbon fiber, it is stronger than many metals by weight, non- magnetic, non-conductive, transparent to electromagnetic radiation, can be molded into complex shapes, and is chemically inert under many circumstances. Applications include aircraft, boats, automobiles, bath tubs and enclosures, swimming pools, hot tubs, septic tanks, water tanks, roofing, pipes, cladding, orthopedic casts, surfboards, and external door skins. Other common names for fiberglass are glass-reinforced plastic (GRP), glass-fiber reinforced plastic (GFRP) or GF ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Lerici-class Minehunter
The ''Lerici'' class is a class of minehunters constructed by Intermarine SpA and owned and operated by the Italian Navy. The class incorporates two subclasses: the first four ships are referred to specifically as the first series of the ''Lerici'' class, while eight more ships produced to a slightly modified design are known as "second series ''Lerici''s" or as the ''Gaeta'' class. The class design has also been used as the basis for ships of the Royal Malaysian Navy (as the ''Mahamiru'' class), the Nigerian Navy, the United States Navy (as the ), the Royal Australian Navy (as the ), and the Royal Thai Navy (as the ''Lat Ya'' class). Three updated vessels were constructed for the Finnish Navy (the ). The Republic of Korea Navy operates an unlicensed derivative, known as the ''Ganggyeong'' class. Design and service history Twelve ships were constructed by Intermarine SpA between 1985 and 1996. The first four, referred to as the ''Lerici'' subclass) were ordered on 7 January 1 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bedok-class Mine Countermeasures Vessel
The ''Bedok'' class are mine countermeasures vessels of the Republic of Singapore Navy (RSN). They play an important role in the maritime security of Singapore, ensuring that the Singapore Strait and the sea lanes surrounding Singapore remain mine-free and open to international shipping. It is estimated that closure of Singapore's ports would result in direct trade losses amounting to more than US$1.2 billion daily, posing a serious threat to Singapore's economy. The four ships form the Sixth Flotilla of the RSN. Planning and acquisition The RSN first acquired mine countermeasures capabilities in 1975, when the United States Navy's and were re-activated by the RSN's engineers and technicians in California. These s were commissioned as RSS ''Jupiter'' and RSS ''Mercury'' respectively. RSS ''Jupiter'' was scrapped on 15 August 1986 and RSS ''Mercury'' was decommissioned on 31 March 1993. The need for modern minehunting vessels saw Singapore entering into an agreement with Swede ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tripartite-class Minehunter
The Tripartite class is a class of minehunters developed from an agreement between the navies of Belgium, France and the Netherlands. A total of 35 ships were constructed for the three navies. The class was constructed in the 1980s–1990s in all three countries, using a mix of minehunting, electrical and propulsion systems from the three member nations. In France, where they are known as the ''Éridan'' class they are primarily used as minehunters, but have been used for minesweeping and ammunition transport in Belgium and the Netherlands, where the Tripartites are known as the ''Alkmaar'' class. In 1992, the Pakistan Navy acquired three vessels from France, one that was already built, one to be built in France and one built in France and Pakistan. Known as the ''Munsif'' class, all three are still in service. The Indonesian Navy acquired two minehunters in the 1990s from the Dutch to a modified design. Known as the ''Pulau Rengat'' class, the two ships are still in service. In ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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List Of Mine Warfare Vessels Of The United States Navy
This is a list of mine warfare vessels of the United States Navy. Ship status is indicated as either currently active (including ready reserve), inactive or precommissioning Ships in the inactive category include only ships in the inactive reserve, ships which have been disposed from US service have no listed status. Ships in the precommissioning category include ships under construction or on order. Overview Mine warfare consists of: minelaying, the deployment of explosive naval mines at sea to sink enemy ships or to prevent their access to particular areas; minesweeping, the removal or detonation of naval mines; and degaussing, the process of decreasing or eliminating a remnant magnetic field in a ship's hull to prevent its detection by magnetic mines. The US Navy has operated ships and craft for all three purposes. Mine planting is the laying and maintenance of controlled mines for harbor defense, which was traditionally a role of the US Army. Classifications Mine warf ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fluid Dynamics
In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids— liquids and gases. It has several subdisciplines, including ''aerodynamics'' (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation. Fluid dynamics offers a systematic structure—which underlies these practical disciplines—that embraces empirical and semi-empirical laws derived from flow measurement and used to solve practical problems. The solution to a fluid dynamics problem typically involves the calculation of various properties of the fluid, such as flow velocity, pressure, density, and temperature, as functions of space and time. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Catamaran
A Formula 16 beachable catamaran Powered catamaran passenger ferry at Salem, Massachusetts, United States A catamaran () (informally, a "cat") is a multi-hulled watercraft featuring two parallel hulls of equal size. It is a geometry-stabilized craft, deriving its stability from its wide beam, rather than from a ballasted keel as with a monohull boat. Catamarans typically have less hull volume, smaller displacement, and shallower draft (draught) than monohulls of comparable length. The two hulls combined also often have a smaller hydrodynamic resistance than comparable monohulls, requiring less propulsive power from either sails or motors. The catamaran's wider stance on the water can reduce both heeling and wave-induced motion, as compared with a monohull, and can give reduced wakes. Catamarans were invented by the Austronesian peoples which enabled their expansion to the islands of the Indian and Pacific Oceans. Catamarans range in size from small sailing or rowing ve ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Voith-Schneider
A cyclorotor, cycloidal rotor, cycloidal propeller or cyclogiro, is a fluid propulsion device that converts shaft power into the acceleration of a fluid using a rotating axis perpendicular to the direction of fluid motion. It uses several blades with a spanwise axis parallel to the axis of rotation and perpendicular to the direction of fluid motion. These blades are cyclically pitched twice per revolution to produce force (thrust or lift) in any direction normal to the axis of rotation. Cyclorotors are used for propulsion, lift, and control on air and water vehicles. An aircraft using cyclorotors as the primary source of lift, propulsion, and control is known as a cyclogyro or cyclocopter. A unique aspect is that it can change the magnitude and direction of thrust without the need of tilting any aircraft structures. The patented application, used on ships with particular actuation mechanisms both mechanical or hydraulic, is named after German company Voith Turbo. Operating princip ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Harbour
A harbor (American English), harbour (British English; see spelling differences), or haven is a sheltered body of water where ships, boats, and barges can be docked. The term ''harbor'' is often used interchangeably with ''port'', which is a man-made facility built for loading and unloading vessels and dropping off and picking up passengers. Ports usually include one or more harbors. Alexandria Port in Egypt is an example of a port with two harbors. Harbors may be natural or artificial. An artificial harbor can have deliberately constructed breakwaters, sea walls, or jettys or they can be constructed by dredging, which requires maintenance by further periodic dredging. An example of an artificial harbor is Long Beach Harbor, California, United States, which was an array of salt marshes and tidal flats too shallow for modern merchant ships before it was first dredged in the early 20th century. In contrast, a natural harbor is surrounded on several sides of land. Examples ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Shipping Channel
In physical geography, a channel is a type of landform consisting of the outline of a path of relatively shallow and narrow body of water or of other fluids (e.g., lava), most commonly the confine of a river, river delta or strait. The word is cognate to canal, and sometimes takes this form, e.g. the Hood Canal. Formation Channel initiation refers to the site on a mountain slope where water begins to flow between identifiable banks.Bierman, R. B, David R. Montgomery (2014). Key Concepts in Geomorphology. W. H. Freeman and Company Publishers. United States. This site is referred to as the channel head and it marks an important boundary between hillslope processes and fluvial processes. The channel head is the most upslope part of a channel network and is defined by flowing water between defined identifiable banks. A channel head forms as overland flow and/or subsurface flow accumulate to a point where shear stress can overcome erosion resistance of the ground surface. Channel hea ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Draft (hull)
The draft or draught of a ship's hull is the vertical distance between the waterline and the bottom of the hull (keel). The draught of the vessel is the maximum depth of any part of the vessel, including appendages such as rudders, propellers and drop keels if deployed. Draft determines the minimum depth of water a ship or boat can safely navigate. The related term air draft is the maximum height of any part of the vessel above the water. The more heavily a vessel is loaded, the deeper it sinks into the water, and the greater its draft. After construction, the shipyard creates a table showing how much water the vessel displaces based on its draft and the density of the water (salt or fresh). The draft can also be used to determine the weight of cargo on board by calculating the total displacement of water, accounting for the content of the ship's bunkers, and using Archimedes' principle. The closely related term "trim" is defined as the difference between the forward and aft ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |