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French Cruiser Dupuy De Lôme
''Dupuy de Lôme'' was an armoured cruiser built for the French Navy (''Marine Nationale'') during the late 1880s and 1890s. She is considered by some to be the world's first armoured cruiser and was intended to attack enemy merchant ships. The ship was named after the naval architect Henri Dupuy de Lôme. ''Dupuy de Lôme''s completion was delayed by almost two years by problems with her boilers, but she was finally commissioned in 1895 and assigned to the Northern Squadron (''Escadre du Nord''), based at Brest, for most of her career. The ship made a number of visits to foreign ports before she began a lengthy reconstruction in 1902. By the time this was completed in 1906, the cruiser was regarded as obsolete and ''Dupuy de Lôme'' was placed in reserve, aside from one assignment in Morocco. The ship was sold to the Peruvian Navy in 1912, but they never paid the last two installments and the ship remained inactive at Brest during World War I. The French agreed to take the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henri Dupuy De Lôme
Stanislas Charles Henri Dupuy de Lôme (; 15 October 18161 February 1885) was a French naval architect. He was the son of a naval officer and was born in Ploemeur near Lorient, Brittany, in western France. He was educated at the École Polytechnique and ENSTA. He was particularly active during the 1840–1870 period. After finishing his professional education, he went to England about 1842, and made a thorough study of iron shipbuilding and steam navigation. He wrote a report, subsequently published under the title of ''Mémoire sur la construction des bâtiments en fer'' in 1844. The first steam battleship After his return from England, Dupuy de Lôme started work at the arsenal in Toulon. At the time the only armed steamships in the French Navy were propelled by paddle-wheels, and there was great opposition to the introduction of steam power into line-of-battle ships. The paddle-wheel was seen to be unsuited to such large fighting vessels, and there was no confidence in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ship Commissioning
Ship commissioning is the act or ceremony of placing a ship in active service and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to placing a warship in active duty with its country's military forces. The ceremonies involved are often rooted in centuries-old naval tradition. Ship naming and launching endow a ship hull with her identity, but many milestones remain before it is completed and considered ready to be designated a commissioned ship. The engineering plant, weapon and Electronics, electronic systems, Galley (kitchen), galley, and other equipment required to transform the new hull into an operating and habitable warship are installed and tested. The prospective commanding officer, ship's officers, the petty officers, and seamen who will form the crew report for training and familiarization with their new ship. Before commissioning, the new ship undergoes sea trials to identify a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacentric Height
The metacentric height (GM) is a measurement of the initial static stability of a floating body. It is calculated as the distance between the centre of gravity of a ship and its '' metacentre''. A larger metacentric height implies greater initial stability against overturning. The metacentric height also influences the natural period of rolling of a hull, with very large metacentric heights being associated with shorter periods of roll which are uncomfortable for passengers. Hence, a sufficiently, but not excessively, high metacentric height is considered ideal for passenger ships. Different centres The ''centre of buoyancy'' is at the centre of mass of the volume of water that the hull displaces. This point is referred to as B in naval architecture. The '' centre of gravity'' of the ship is commonly denoted as point G or CG. When a ship is at equilibrium, the centre of buoyancy is vertically in line with the centre of gravity of the ship. The metacentre is the point where th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Load
The displacement or displacement tonnage of a ship is its weight. As the term indicates, it is measured indirectly, using Archimedes' principle, by first calculating the volume of water displaced by the ship, then converting that value into weight. Traditionally, various measurement rules have been in use, giving various measures in long tons. Today, tonnes are more commonly used. Ship displacement varies by a vessel's degree of load, from its empty weight as designed (known as "lightweight tonnage") to its maximum load. Numerous specific terms are used to describe varying levels of load and trim, detailed below. Ship displacement should not be confused with measurements of volume or capacity typically used for commercial vessels and measured by tonnage: net tonnage and gross tonnage. Calculation The process of determining a vessel's displacement begins with measuring its draft.George, 2005. p. 5. This is accomplished by means of its "draft marks". A merchant vessel has three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Draft (ship)
The draft or draught of a ship is a determined depth of the vessel below the waterline, measured vertically to its hull's lowest—its propellers, or keel, or other reference point. Draft varies according to the loaded condition of the ship. A deeper draft means the ship will have greater vertical depth below the waterline. Draft is used in under keel clearance calculations, where the draft is calculated with the available depth of water (from Electronic navigational charts) to ensure the ship can navigate safely, without grounding. Navigators can determine their draught by calculation or by visual observation (of the ship's painted load lines). Related terminology A ship's draft/draught is the "depth of the vessel below the waterline measured vertically to the lowest part of the hull, propellers, or other reference point". That is, the draft or draught is the maximum depth of any part of the vessel, including appendages such as rudders, propellers and drop keels if depl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beam (nautical)
The beam of a ship is its width at its widest point. The maximum beam (BMAX) is the distance between planes passing through the outer sides of the ship, beam of the hull (BH) only includes permanently fixed parts of the hull, and beam at waterline (BWL) is the maximum width where the hull intersects the surface of the water. Generally speaking, the wider the beam of a ship (or boat), the more initial stability it has, at the expense of secondary stability in the event of a capsize, where more energy is required to right the vessel from its inverted position. A ship that heels on her ''beam ends'' has her deck beams nearly vertical. Typical values Typical length-to-beam ratios ( aspect ratios) for small sailboats are from 2:1 (dinghies to trailerable sailboats around ) to 5:1 (racing sailboats over ). Large ships have widely varying beam ratios, some as large as 20:1. Rowing shells designed for flatwater racing may have length to beam ratios as high as 30:1, while a cora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casemate
A casemate is a fortified gun emplacement or armoured structure from which guns are fired, in a fortification, warship, or armoured fighting vehicle.Webster's New Collegiate Dictionary When referring to antiquity, the term "casemate wall" means a double city wall with the space between the walls separated into chambers, which could be filled up to better withstand battering rams in case of siege (see .) In its original early modern meaning, the term referred to a vaulted chamber in a fort, which may have been used for storage, accommodation, or artillery which could fire through an opening or embrasure. Although the outward faces of brick or masonry casemates proved vulnerable to advances in artillery performance, the invention of reinforced concrete allowed newer designs to be produced well into the 20th century. With the introduction of ironclad warships, the definition was widened to include a protected space for guns in a ship, either within the hull or in the low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gun Turret
A gun turret (or simply turret) is a mounting platform from which weapons can be fired that affords protection, visibility and ability to turn and aim. A modern gun turret is generally a rotatable weapon mount that houses the crew or mechanism of a projectile-firing weapon and at the same time lets the weapon be aimed and fired in some degree of azimuth and elevation (cone of fire). Description Rotating gun turrets protect the weapon and its crew as they rotate. When this meaning of the word "turret" started being used at the beginning of the 1860s, turrets were normally cylindrical. Barbettes were an alternative to turrets; with a barbette the protection was fixed, and the weapon and crew were on a rotating platform inside the barbette. In the 1890s, armoured hoods (also known as "gun houses") were added to barbettes; these rotated with the platform (hence the term "hooded barbette"). By the early 20th century, these hoods were known as turrets. Modern warships have gun-m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quick-firing Gun
A quick-firing or rapid-firing gun is an artillery piece, typically a gun or howitzer, that has several characteristics which taken together mean the weapon can fire at a fast rate. Quick-firing was introduced worldwide in the 1880s and 1890s and had a marked impact on war both on land and at sea. Characteristics The characteristics of a quick-firing artillery piece are: *A breechloader, breech-loading weapon with a breech mechanism that allows rapid reloading *Single-part casing (ammunition), cased ammunition, i.e. a cartridge (firearms), cartridge containing both shell and propellant *Recoil buffers to limit recoil, so the barrel can quickly return to the same position after firing *The use of smokeless powder – nitrocellulose, nitroglycerine, or cordite – which create far less smoke than gunpowder, meaning that gun crews could still see their target These innovations, taken together, meant that the quick-firer could fire aimed shells much more rapidly than an older weapon. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protected Cruiser
Protected cruisers, a type of cruiser of the late 19th century, took their name from the armored deck, which protected vital machine-spaces from fragments released by explosive shells. Protected cruisers notably lacked a belt of armour along the sides, in contrast to armored cruisers which carried both deck and belt armour. Outside of a handful of very large designs in the major navies (which preceded the revival of armored cruisers), the majority of protected cruisers were of 'second-' or 'third-class' types, lighter in displacement and mounting fewer and/or lighter guns than armored cruisers. By the early 20th-century, with the advent of increasingly lighter yet stronger armour, even smaller vessels could afford some level of both belt and deck armour. In the place of protected cruisers, these new ' light armored cruisers' would evolve into light cruisers and heavy cruisers, the former especially taking on many of the roles originally envisioned for protected cruisers. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jeune École
The ''Jeune École'' ("Young School") was a strategic naval concept developed during the 19th century. It advocated the use of small, heavily armed vessels to combat larger battleships, and the use of commerce raiders to cripple the trade of the rival nation. The idea was developed among French naval theorists: the French government had the second largest navy of the time, and the theorists desired to counteract the strength of the larger British Royal Navy. Small units against battleships One of the first proponents of the ''Jeune École'' was the artillery general Henri-Joseph Paixhans, who invented explosive shell guns for warships during the 1820s. He advocated the use of these powerful guns on numerous small steam warships that could destroy much larger battleships. Later, the French Navy developed the concept more elaborately as it experimented with torpedoes and torpedo boats. The French Navy became one of the strongest proponents of this combat system by the end of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ship Breaking
Ship breaking (also known as ship recycling, ship demolition, ship scrapping, ship dismantling, or ship cracking) is a type of ship disposal involving the breaking up of ships either as a source of Interchangeable parts, parts, which can be sold for re-use, or for the extraction of raw materials, chiefly scrap. Modern ships have a lifespan of 25 to 30 years before corrosion, Fatigue (material), metal fatigue and a lack of parts render them uneconomical to operate. Ship-breaking allows the materials from the ship, especially steel, to be recycled and made into new products. This lowers the demand for mined iron ore and reduces energy use in the steelmaking process. Fixtures and other equipment on board the vessels can also be reused. While ship-breaking is sustainable, there are concerns about its use by poorer countries without stringent environmental legislation. It is also labour-intensive, and considered one of the world's most dangerous industries. In 2012, roughly 1,250 oce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
