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Calvi Class Submarine
The ''Calvi'' class was a class of three submarines built by Oderno-Terni-Orlando in Genoa for the Royal Italian Navy ( it, Regia Marina). The submarines were built in 1935, and all three served in the Mediterranean at the start of the Second World War. The boats were transferred to the BETASOM Atlantic submarine base at Bordeaux in August 1940. In December 1941 the boats were used for a rescue mission of 254 sailors from the sunken . After ''Calvi'' had been sunk, ''Finzi'' and ''Tazzoli'' were selected for conversion to " transport submarines" in order to exchange rare or irreplaceable trade goods with Japan. Cargo capacity of 160 tons reduced reserve buoyancy from 20–25% to 3.5–6%; and armament was reduced to defensive machine guns. Design and description The ''Calvi'' class was an improved and enlarged version of the preceding submarine cruisers. They displaced surfaced and submerged. The submarines were long, had a beam of and a draft of . They had an operati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OTO Melara
OTO Melara was a subsidiary of the Italian company Finmeccanica, today Leonardo, active in the defence sector, with factories in Brescia and La Spezia. The Mod 56 pack howitzer, in service throughout the world, and the 76mm naval gun, adopted by 53 navies and installed on over 1,000 naval vessels, are among OTO Melara's best known weapons since World War II. From 1 January 2016, the activities of OTO Melara merged into Leonardo's Defence Systems Division, within the Electronics, Defence and Security Systems Sector. History Pre–World War I It was founded in 1905 as a joint venture of Vickers and Terni Steelworks, Cantiere navale fratelli Orlando and Cantieri navali Odero. Investment was also provided by Giuseppe Orlando and Attilio Odero. During World War I, Vickers Terni produced many weapons with calibre 40 mm and upwards. In 1929 the company was renamed Odero Terni Orlando with the abbreviation OTO. During World War II, mostly heavy guns for battleships were pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BETASOM
BETASOM (an Italian language acronym of ''Bordeaux Sommergibile'' or ''Sommergibili'') was a submarine base established at Bordeaux, France by the Italian '' Regia Marina Italiana'' during World War II. From this base, Italian submarines participated in the Battle of the Atlantic from 1940 to 1943 as part of the Axis anti-shipping campaign against the Allies. Establishment Axis naval co-operation started after the signing of the Pact of Steel in June 1939 with meetings in Friedrichshafen, Germany, and an agreement to exchange technical information. After the Italian entry into the war and the Fall of France, the Italian Royal Navy established a submarine base at Bordeaux, which was within the German occupation zone. The Italians were allocated a sector of the Atlantic south of Lisbon to patrol. The base was opened in August 1940, and in 1941 the captured French passenger ship was used as a depot ship before being returned to the Vichy French Government in June 1942. Admir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pennant Number
In the Royal Navy and other navies of Europe and the Commonwealth of Nations, ships are identified by pennant number (an internationalisation of ''pendant number'', which it was called before 1948). Historically, naval ships flew a flag that identified a flotilla or type of vessel. For example, the Royal Navy used a red burgee for torpedo boats and a pennant with an H for torpedo boat destroyers. Adding a number to the type-identifying flag uniquely identified each ship. In the current system, a letter prefix, called a ''flag superior'', identifies the type of ship, and numerical suffix, called a flag inferior, uniquely identifies an individual ship. Not all pennant numbers have a flag superior. Royal Navy systems The Royal Navy first used pennants to distinguish its ships in 1661 with a proclamation that all of his majesty's ships must fly a union pennant. This distinction was further strengthened by a proclamation in 1674 which forbade merchant vessels from flying any pennants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-aircraft Warfare
Anti-aircraft warfare, counter-air or air defence forces is the battlespace response to aerial warfare, defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It includes Surface-to-air missile, surface based, subsurface (Submarine#Armament, submarine launched), and air-based weapon systems, associated sensor systems, command and control arrangements, and passive measures (e.g. barrage balloons). It may be used to protect naval, ground, and air forces in any location. However, for most countries, the main effort has tended to be homeland defence. NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defense, Missile defence is an extension of air defence, as are initiatives to adapt air defence to the task of intercepting any projectile in flight. In some countries, such as Britain and Germany during the World War II, Second World War, the Soviet Union, and modern NATO a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conning Tower
A conning tower is a raised platform on a ship or submarine, often armored, from which an officer in charge can conn the vessel, controlling movements of the ship by giving orders to those responsible for the ship's engine, rudder, lines, and ground tackle. It is usually located as high on the ship as practical, to give the conning team good visibility of the entirety of the ship, ocean conditions, and other vessels. The naval term "conn" may derive from the Middle English ''conne'' (study, become acquainted with) or French ''conduire'' from Latin ''conducere'' (conduct). Surface ships On surface ships, the conning tower was a feature of all battleships and armored cruisers from about 1860 to the early years of World War II. Located at the front end of the superstructure, the conning tower was a heavily armored cylinder, with tiny slit windows on three sides providing a reasonable field of view. Designed to shield just enough personnel and devices for navigation during battle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such a device was called an automotive, automobile, locomotive, or fish torpedo; colloquially a ''fish''. The term ''torpedo'' originally applied to a variety of devices, most of which would today be called naval mine, mines. From about 1900, ''torpedo'' has been used strictly to designate a self-propelled underwater explosive device. While the 19th-century battleship had evolved primarily with a view to engagements between armored warships with naval artillery, large-caliber guns, the invention and refinement of torpedoes from the 1860s onwards allowed small torpedo boats and other lighter surface combatant , surface vessels, submarines/submersibles, even improvised fishing boats or frogmen, and later light aircraft, to destroy large shi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propeller Shaft
A drive shaft, driveshaft, driving shaft, tailshaft (Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power and torque and rotation, usually used to connect other components of a drivetrain that cannot be connected directly because of distance or the need to allow for relative movement between them. As torque carriers, drive shafts are subject to torsion and shear stress, equivalent to the difference between the input torque and the load. They must therefore be strong enough to bear the stress, while avoiding too much additional weight as that would in turn increase their inertia. To allow for variations in the alignment and distance between the driving and driven components, drive shafts frequently incorporate one or more universal joints, jaw couplings, or rag joints, and sometimes a splined joint or prismatic joint. History The term ''driveshaft'' first appeared during the mid-19th centu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submarine Depth Ratings
Depth ratings are primary design parameters and measures of a submarine's ability to operate underwater. The depths to which submarines can dive are limited by the strengths of their hulls. Ratings The hull of a submarine must be able to withstand the forces created by the outside water pressure being greater than the inside air pressure. The outside water pressure increases with depth and so the stresses on the hull also increase with depth. Each 10 metres (33 feet) of depth puts another atmosphere (1 bar, 14.7 psi, 101 kPa) of pressure on the hull, so at 300 metres (1,000 feet), the hull is withstanding thirty atmospheres (30 bar, 441 psi, 3,000 kPa) of water pressure. Test depth The maximum depth at which a submarine is permitted to operate under normal peacetime circumstances, and is tested during sea trials. The test depth is set at two-thirds (0.66) of the design depth for United States Navy submarines, while the Royal Navy sets test depth at 4/7 (0.57) the design depth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
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 extremities 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 cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Displacement (ship)
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" (or "load lines"). A mer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submarine Cruiser
A cruiser submarine was a very large submarine designed to remain at sea for extended periods in areas distant from base facilities. Their role was analogous to surface cruisers, cruising distant waters, commerce raiding, and scouting for the battle fleet. Cruiser submarines were successful for a brief period of World War I, but were less successful than smaller submarines during World War II. Large submarines remained vulnerable to damage from defensively equipped merchant ships (DEMS), were slow to dive if found by aircraft, offered a large sonar echo surface, and were less able to defensively maneuver during depth charge attacks.Blair, p.501 History The cruiser submarine concept originated during the unrestricted submarine warfare campaign of 1917. Three German Type U 139 submarines and seven former merchant submarines, each armed with two guns, patrolled areas distant from their North Sea bases to sink Allied merchant shipping as part of an effort to end World War I by starv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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