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German Type XIV Submarine
The Type XIV U-boat was designed to resupply other U-boats,Rössler (2001), p. 151. being the only submarine tenders built which were not surface ships. It was nicknamed in German the "''Milchkuh/Milchkühe (pl.)''" (English: milk cows).Williamson (2005), p. 16. Design The Type XIV was based on the Type IXD long-range U-boat design, but with a shorter and deeper hull. The boats had a displacement of when at the surface and while submerged. The U-boats had a total length of , a pressure hull length of , a beam of , a height of , and a draught of . The submarines were powered by two Germaniawerft supercharged four-stroke, six-cylinder diesel engines producing a total of for use while surfaced, two Siemens-Schuckert 2 GU 345/38-8 double-acting electric motors producing a total of for use while submerged. They had two shafts and two propellers. The boats were capable of operating at depths of up to . The submarines had a maximum surface speed of and a maximum submerged s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vickers Wellington
The Vickers Wellington (nicknamed the Wimpy) is a British twin-engined, long-range medium bomber. It was designed during the mid-1930s at Brooklands in Weybridge, Surrey. Led by Vickers-Armstrongs' chief designer Rex Pierson, a key feature of the aircraft is its geodetic airframe fuselage structure, which was principally designed by Barnes Wallis. Development had been started in response to Air Ministry List Of Air Ministry Specifications, Specification B.9/32, issued in the middle of 1932, for a bomber for the Royal Air Force. This specification called for a twin-engined day bomber capable of delivering higher performance than any previous design. Other aircraft developed to the same specification include the Armstrong Whitworth Whitley and the Handley Page Hampden. During the development process, performance requirements such as for the tare weight changed substantially, and the engine used was not the one originally intended. Despite the original specification, the Wellingto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propeller
A propeller (often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working fluid such as water or air. Propellers are used to pump fluid through a pipe or duct, or to create thrust to propel a boat through water or an aircraft through air. The blades are shaped so that their rotational motion through the fluid causes a pressure difference between the two surfaces of the blade by Bernoulli's principle which exerts force on the fluid. Most marine propellers are screw propellers with helical blades rotating on a propeller shaft (ship), propeller shaft with an approximately horizontal axis. History Early developments The principle employed in using a screw propeller is derived from stern sculling. In sculling, a single blade is moved through an arc, from side to side taking care to keep presenting the blade to the wat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultra (cryptography)
Ultra was the designation adopted by United Kingdom, British military intelligence in June 1941 for wartime signals intelligence obtained by breaking high-level encrypted enemy radio and teleprinter communications at the Government Code and Cypher School (GC&CS) at Bletchley Park. ''Ultra'' eventually became the standard designation among the western Allies of World War II, Allies for all such intelligence. The name arose because the intelligence obtained was considered more important than that designated by the highest British Classified information, security classification then used (''Most Secret'' and so was regarded as being ''Ultra Secret''. Several other cryptonyms had been used for such intelligence. The code name "Boniface" was used as a cover name for ''Ultra''. In order to ensure that the successful code-breaking did not become apparent to the Germans, British intelligence created a fictional MI6 master spy, Boniface, who controlled a fictional series of agents throug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allies Of World War II
The Allies, formally referred to as the United Nations from 1942, were an international Coalition#Military, military coalition formed during World War II (1939–1945) to oppose the Axis powers. Its principal members were the "Four Policemen, Big Four" – the United Kingdom, United States, Soviet Union, and Republic of China (1912–1949), China. Membership in the Allies varied during the course of the war. When the conflict broke out on 1 September 1939, the Allied coalition consisted of the United Kingdom, French Third Republic, France, and Second Polish Republic, Poland, as well as their respective Dependent territory, dependencies, such as British Raj, British India. They were joined by the independent dominions of the British Commonwealth: Canada, Australia, Dominion of New Zealand, New Zealand and Union of South Africa, South Africa. Consequently, the initial alliance resembled Allies of World War I, that of the First World War. As Axis forces began German invasion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battle Of The Atlantic
The Battle of the Atlantic, the longest continuous military campaign in World War II, ran from 1939 to the defeat of Nazi Germany in 1945, covering a major part of the naval history of World War II. At its core was the Allies of World War II, Allied naval Blockade of Germany (1939–1945), blockade of Germany, announced the day after the declaration of war, and Germany's subsequent counter-blockade. The campaign peaked from mid-1940 to the end of 1943. The Battle of the Atlantic pitted U-boats and other warships of the German (navy) and aircraft of the (air force) against the Royal Navy, Royal Canadian Navy, United States Navy, and Merchant Navy (United Kingdom), Allied merchant shipping. Convoys, coming mainly from North America and predominantly going to the United Kingdom and the Soviet Union, were protected for the most part by the British and Canadian navies and air forces. These forces were aided by ships and aircraft of the United States beginning on 13 September 1941. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Second Happy Time
The Second Happy Time (; officially (), and also known among German submarine commanders as the "American Shooting Season") was a phase in the Battle of the Atlantic during which Axis submarines attacked merchant shipping and Allied naval vessels along the east coast of North America. The First Happy Time was in 1940–41 in the North Atlantic and North Sea. Adolf Hitler and Benito Mussolini declared war on the United States on 11 December 1941, and as a result their navies could begin the Second Happy Time. The Second Happy Time lasted from January 1942 to about August of that year and involved several German naval operations, including Operation Neuland. German submariners named it the "Happy Time" or the "Golden Time", as defense measures were weak and disorganized, and the U-boats were able to inflict massive damage with little risk. During this period, Axis submarines sank 609 ships totaling , against a loss of only 22 U-boats. This led to the loss of thousands of live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type VII U-boat
Type VII U-boats were the most common type of German World War II U-boat. 704 boats were built by the end of the war. The type had several modifications. The Type VII was the most numerous U-boat type to be involved in the Battle of the Atlantic. The lone surviving example, , is on display at the Laboe Naval Memorial located in Laboe, Schleswig-Holstein, Germany. At the start of the Second World War the ''Type VII'' class wastogether with the British ''U'', ''S'' and ''T'' class and Dutch ''O 21'' classone of the most advanced submarine classes in service. Design After the defeat in World War I, the Treaty of Versailles forbade Germany to build submarines. Germany circumvented the treaty by setting up the Dutch dummy company ''NV Ingenieurskantoor voor Scheepsbouw Den Haag'' (I.v.S) which continued to design submarines. Based on the World War I design of the Type UB III and its never-built successors Type UF and Type UG, IVS designed the Vetehinen-class submarine and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mid-Atlantic Gap
The Mid-Atlantic gap is a geographical term applied to an undefended area of the Atlantic Ocean during the Battle of the Atlantic in the Second World War. The region was beyond the reach of land-based RAF Coastal Command antisubmarine (A/S) aircraft. This resulted in heavy merchant shipping losses to U-boats. It is frequently known as The Black Pit, as well as the Atlantic Gap, Air Gap, Greenland Gap, Black Gap, or just "the Gap". The gap was eventually closed in May 1943, as growing numbers of VLR Liberators (Very Long Range models) and escort carriers became available, and as basing problems were addressed. History The Royal Air Force (RAF)'s Coastal Command, when it was created in 1936, was given responsibility for antisubmarine warfare (A/S or ASW) patrol. It was equipped only with small numbers of short-ranged aircraft, the most common being the Avro Anson (which was obsolete by the start of the Second World War) and Vickers Vildebeest (which was obsolete); for a time, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-aircraft Warfare
Anti-aircraft warfare (AAW) is the counter to aerial warfare and includes "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It encompasses surface-based, subsurface (Submarine#Armament, submarine-launched), and air-based weapon systems, in addition to associated sensor systems, command and control arrangements, and passive measures (e.g. barrage balloons). It may be used to protect naval, army, ground, and air forces in any location. However, for most countries, the main effort has tended to be homeland defense. Missile defense, Missile defense is an extension of air defence, as are initiatives to adapt air defence to the task of intercepting any projectile in flight. Most modern anti-aircraft (AA) weapons systems are optimized for short-, medium-, or long-range air defence, although some systems may incorporate multiple weapons (such as both autocannons and surface-to-air missiles). 'Layered air defence' usually refers to multiple 't ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Military Prison
A military prison is a prison operated by a military. Military prisons are used variously to house prisoners of war, unlawful combatants, those whose freedom is deemed a national security risk by the military or national authorities, and members of the military found guilty of military offenses. There are two types: penal and confinement-oriented, where captured enemy combatants are confined for military reasons until hostilities cease. Most militaries have some sort of military police unit operating at the divisional level or below to perform many of the same functions as civilian police, from traffic-control to the arrest of violent offenders and the supervision of detainees and prisoners of war. Australia The Australian Defence Force states it has no prisons. Instead they have a single facility, the Defence Force Correctional Establishment (Australia), Defence Force Correctional Establishment, which aims to rehabilitate members who have been sentenced to detention for breachi ... [...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, 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 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 large-caliber guns, the invention and refinement of torpedoes from the 1860s onwards allowed small torpedo boats and other lighter surface vessels, submarines/submersibles, even improvised fishing boats or frogmen, and later light aircraft, to destroy large ships without the need of large guns, though somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submarine
A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or informally to refer to remotely operated vehicles and Autonomous underwater vehicle, robots, or to medium-sized or smaller vessels (such as the midget submarine and the wet sub). Submarines are referred to as ''boats'' rather than ''ships'' regardless of their size. Although experimental submarines had been built earlier, submarine design took off during the 19th century, and submarines were adopted by several navies. They were first used widely during World War I (1914–1918), and are now used in many navy, navies, large and small. Their military uses include: attacking enemy surface ships (merchant and military) or other submarines; aircraft carrier protection; Blockade runner, blockade running; Ballistic missile submarine, nuclear deterrenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
