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Iranian High-aspect-ratio Twin-hull Vessels
A high-aspect-ratio twin-hull vessel (acronymed HARTH) refers to a certain design of catamaran vessels with small waterplane area. These vessels are built and used by the Islamic Revolutionary Guard Corps (IRGC) of Iran. Such design is considered relatively rare in military usage. Design The design of vessels is being described as looking "almost like a pond skater" because of the superstructure sitting above tall legs. Due to the large length of the hulls in the water (also known as pontoons) and also the high height of the deck above the surface, it has a high length-to-width ratio (and is thus called high-aspect-ratio). This design enables small speedboats to move under the ship, which can technically make certain tactical scenarios possible. In comparison to a conventional catamaran, HARTH design allows decreasing the drag forces of the hull and thus breaking the seawater during sailing more easily, as well as more transverse stability in harsh sea states as a result of low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Shahid Soleimani Missile Corvette
''Shahid Soleimani'' (Persian: شهید سلیمانی) is the lead ship of an Iranian class of missile corvettes with the same name. It was built by the Shahid Mahallati Shipyard and is operated by the Islamic Revolutionary Guard Corps Navy of Iran. Design Hull The ship has a catamaran (twin hull) design with sharp angles to give it a more stealthy design. Its design has been compared to the Chinese Type 22 missile boat and the Taiwanese ''Tuo Chiang'' class. According to Iranian officials the ship's hull is made of aluminium instead of steel which decreases the weight and is a new innovation in the Iranian shipbuilding industry. Armament This warship is equipped with six anti-ship cruise missiles including four long-range ones (likely Noor or Ghadir) and two short-range anti-ship missiles (likely Nasir) in an order of two long-range and one short-range box launchers on each side behind the superstructure. It is also the first Iranian warship to be equipped with VLS. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ship Classes Of The Islamic Revolutionary Guard Corps
A ship is a large watercraft that travels the world's oceans and other sufficiently deep waterways, carrying cargo or passengers, or in support of specialized missions, such as defense, research, and fishing. Ships are generally distinguished from boats, based on size, shape, load capacity, and purpose. Ships have supported exploration, trade, warfare, migration, colonization, and science. After the 15th century, new crops that had come from and to the Americas via the European seafarers significantly contributed to world population growth. Ship transport is responsible for the largest portion of world commerce. The word ''ship'' has meant, depending on the era and the context, either just a large vessel or specifically a ship-rigged sailing ship with three or more masts, each of which is square-rigged. As of 2016, there were more than 49,000 merchant ships, totaling almost 1.8 billion dead weight tons. Of these 28% were oil tankers, 43% were bulk carriers, and 13% were cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iranian Naval Rigid Inflatable Speedboats
Various series of rigid inflatable boat (RIB) are operated by naval forces of Iran. Based on a design by Italian Fabio Buzzi, they have been manufactured and modified in Iran. History The cooperation between FB Design and Iranians started in 1998, when frames and blueprints of patrol boat ''Levriero'' was purchased by Iran. It is likely that Shahid Joulaee Marine Industries (subordinate to Marine Industries Organization) obtained a license to produce RIB-33SC and FB-55SC models domestically. In 2005, American authorities questioned FB Design about their deals with Iran, effectively putting an end to the cooperation. Iran has reportedly altered some original designs and manufactured similar modifications. Types According to 2015 edition of ''Jane's Fighting Ships'', Iran is known to operate the following models and modifications of rigid inflatable boat: *RIB 42SC ( long, at least one in service) *FB 55 ( long, at least one in service) *FB 38 ( long, at least two in service) *RI ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type 22 Missile Boat
The Type 22 ( NATO designation: ''Houbei'' class) missile boat is a ship class in the Chinese People's Liberation Army Navy. The first boat was launched in April 2004 by the Hudong-Zhonghua Shipyard at Shanghai. The boats incorporate stealth features and are based on Australian-designed wave-piercing catamaran hulls that are more stable than other fast missile craft in high sea conditions. 82 of these missile boats are currently in service with three flotillas having been produced over a span of seven years, operating in squadrons of eight vessels each.This is What a Chinese Stealth Warship Looks Like on Radar ''''. 27 Sept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bandar Abbas
Bandar Abbas or Bandar-e ‘Abbās ( fa, , , ), is a port city and capital of Hormozgān Province on the southern coast of Iran, on the Persian Gulf. The city occupies a strategic position on the narrow Strait of Hormuz (just across from Musandam Governorate, Oman), and it is the location of the main base of the Iranian Navy. Bandar Abbas is also the capital and largest city of Bandar Abbas County. At the 2016 census, its population was 526,648. Etymology Bandar Abbas has always been a port, and as such its various names have all reflected this function. The most common name over time, Gameroon, traditionally derived from Turkish ''gümrük'', "customhouse" (from Late Greek ''kommerkion'', from Latin ''commercium'', "commerce"), but is now speculated to come from Persian ''kamrūn'', "shrimp" (in Portuguese: ''camarão'', similar to the former Portuguese name). Its current name derives from that of Abbas the Great () paired with ''bandar'' - "port", meaning "Port of Abbas" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bushehr
Bushehr, Booshehr or Bushire ( fa, بوشهر ; also romanised as ''Būshehr'', ''Bouchehr'', ''Buschir'' and ''Busehr''), also known as Bandar Bushehr ( fa, ; also romanised as ''Bandar Būshehr'' and ''Bandar-e Būshehr''), previously Antiochia in Persis ( grc, Ἀντιόχεια τῆς Περσίδος, Antiócheia tês Persídos) and Bukht Ardashir, is the capital city of Bushehr Province, Iran and a port city in south of Iran. At the 2006 census, its population was 161,674, in 40,771 families. Bushehr lies in a vast plain running along the coastal region on the Persian Gulf coast of south-western Iran. It is built near the ancient port city of Rishahr (Sassanian, Riv Ardasher). It was the chief seaport of the country and is the administrative center of its province. Its location is about south of Tehran. Bushehr has a Desert climate#Hot desert climates, desert climate. Bushehr was the main trade center of Iran in the past centuries. The city structures are traditional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ship Motions
Ship motions are defined by the six degrees of freedom that a ship, boat or any other craft can experience. Reference axes The '' vertical/Z axis'', or ''yaw axis'', is an imaginary line running vertically through the ship and through its centre of mass . A yaw motion is a side-to side movement of the bow and stern of the ship. The '' transverse/Y axis'', ''lateral axis'', or ''pitch axis'' is an imaginary line running horizontally across the ship and through the centre of mass. A pitch motion is an up-or-down movement of the bow and stern of the ship. The '' longitudinal/X axis'', or ''roll axis'', is an imaginary line running horizontally through the length of the ship, through its centre of mass, and parallel to the ''waterline''. A roll motion is a side-to-side or port-starboard tilting motion of the superstructure around this axis. Rotational There are three special axes in any ship, called longitudinal, transverse and vertical axes. The movements around them a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small-waterplane-area Twin Hull
A small waterplane area twin hull, better known by the acronym SWATH, is a catamaran design that minimizes hull cross section area at the sea's surface. Minimizing the ship's volume near the surface area of the sea, where wave energy is located, minimizes a vessel's response to sea state, even in high seas and at high speeds. The bulk of the displacement necessary to keep the ship afloat is located beneath the waves, where it is less affected by wave action. Wave excitation drops exponentially as depth increases, so wave action normally does not affect a submerged submarine at all. Placing the majority of a ship's displacement under the waves is similar in concept to creating a ship that rides atop twin submarines. Effects The twin-hull design provides a stable platform and large, broad decks. Compared with conventional catamarans, SWATH vessels have more surface drag, but less wave drag. They are less susceptible to wave motion but more sensitive to payload, which affect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drag (physics)
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface. Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity. Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number. Even though the ultimate cause of drag is viscous friction, turbulent drag is independent of viscosity. Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path. Examples Examples of drag include the component of the net aerodynamic or hydrodynamic force acting opposite to the di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deck (ship)
A deck is a permanent covering over a compartment or a hull of a ship. On a boat or ship, the primary or upper deck is the horizontal structure that forms the "roof" of the hull, strengthening it and serving as the primary working surface. Vessels often have more than one level both within the hull and in the superstructure above the primary deck, similar to the floors of a multi-storey building, that are also referred to as decks, as are certain compartments and decks built over specific areas of the superstructure. Decks for some purposes have specific names. Structure The main purpose of the upper or primary deck is structural, and only secondarily to provide weather-tightness and support people and equipment. The deck serves as the lid to the complex box girder which can be identified as the hull. It resists tension, compression, and racking forces. The deck's scantling is usually the same as the topsides, or might be heavier if the deck is expected to carry heavier loads ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_Class_Fast_Attack_Craft.JPG "Click for more on -> Type 22 Missile Boat")
_and_battleship_in_typhoon_1944.jpeg "Click for more on -> Ship Motions")
