1.
Trident nuclear programme
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It is operated by the Royal Navy and based at Clyde Naval Base on the west coast of Scotland,25 miles from Glasgow—Scotlands largest city and the UKs third largest city. At least one submarine is always on patrol to provide a continuous at-sea capability, each one is armed with up to 8 missiles and 40 warheads, their capacity is much larger. The programme was announced in July 1980 and patrols began in December 1994, since tactical WE.177 free-fall bombs were decommissioned in 1998, Trident has been the only nuclear weapon system that is operated by the UK. Its stated purpose by the Ministry of Defence is to deter the most extreme threats to our security and way of life. Trident replaced the submarine-based Polaris system, in operation from 1968 until 1996, a programme for the replacement of the Vanguard-class is under way. Trident would replace the Polaris system of four Resolution-class submarines equipped with U. S. -built Polaris A3 missiles and these missiles were originally armed with triple ET.317 warheads aimed at a single target, later upgraded by the UK Chevaline programme to two hardened warheads. Following the acceleration of the U. S. Trident II D-5 programme, under the agreement, the UK would lease 65 Trident II D-5 missiles from a larger pool of weapons based at Naval Submarine Base Kings Bay in the United States. The U. S. would maintain and support the missiles, the option for a fifth submarine was discussed at the time but later discounted, and the number of missiles leased was later reduced from 65 to 58. Tridents future was secured the year when the Conservative Party won the 1983 general election. The Vanguard-class submarines were built between 1986 and 1998 by Vickers at Barrow-in-Furness, Cumbria, the first British Trident missile was test-fired from HMS Vanguard on 26 May 1994, and the submarine began its first patrol in December of that year. According to the Royal Navy, at least one submarine has always been on ever since. Trident has been the UKs sole nuclear weapons system since the retirement of the WE.177 tactical nuclear weapon following the 1998 Strategic Defence Review, subsequent media reports said the delay was at the request of the United States. Successful Royal Navy test firings had occurred in 2000,2005,2009 and 2012 and they are infrequent due to the missiles £17 million price tag. In total, there have been 161 successful test flights of the D5 missile since design completion in 1989, fewer than 10 test flights have been failures, and the Royal Navy is not known to have had a previous failure. The Trident programme was initiated during the Cold War, and its capabilities were designed to deter powerful Warsaw Pact forces. By the time of the first Vanguard patrol in December 1994, the Soviet Union no longer existed, the final decision on firing the missiles is the responsibility of the prime minister of the United Kingdom. Upon taking office, the prime minister writes four identical letters of last resort, if contact with the UK is lost, the commanding officer of a submarine has to follow the instructions in the letter if they believe that the United Kingdom has suffered an overwhelming attack. Options include retaliating with nuclear weapons, not retaliating, and putting the submarine under the command of an ally, the exact content of the letters is never disclosed, and they are destroyed without being read upon the election of a new prime minister
2.
USS Francis Scott Key (SSBN-657)
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The Francis Scott Key was part of Submarine Squadron 16 based in Rota, Spain. The squadron and submarines moved to Kings Bay, Georgia in 1979, the Key conducted the first submerged launch of a Trident missile in 1979. She also became the first submarine to go on deterrent patrol with Trident I missiles, the Gold crew performed the submarines last SSBN deterrent patrol, Patrol #72, in 1992. The Key combined crews and changed homeport from Charleston, SC to Pearl Harbor, Francis Scott Key was decommissioned on 2 September 1993 with Commander Carl D. Olson in command, and stricken from the Naval Vessel Register the same day. Her scrapping via the U. S. Navys Nuclear-Powered Ship and this article includes information collected from the Naval Vessel Register, which, as a U. S. government publication, is in the public domain. The entry can be found here, photo gallery of USS Francis Scott Key at NavSource Naval History SSBN657 USS Francis Scott Key Crew Home Page. USS Francis Scott Key Navy Unit Commendation September 1978 - October 1979
3.
Submarine-launched ballistic missile
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A submarine-launched ballistic missile is a ballistic missile capable of being launched from submarines. Modern variants usually deliver multiple independently targetable reentry vehicles each of which carries a nuclear warhead, submarine-launched ballistic missiles operate in a different way from submarine-launched cruise missiles. Modern submarine-launched ballistic missiles are closely related to ballistic missiles. The war ended before it could be tested, but the engineers who had worked on it went on to work for the USA and USSR on their SLBM programs. These and other early SLBM systems required vessels to be surfaced when they fired missiles, a converted Project 611 submarine launched the worlds first SLBM, an R-11FM on 16 September 1955. Five additional Project V611 and AV611 submarines became the worlds first operational ballistic missile submarines with two R-11FM missiles each, entering service in 1956–57. The United States Navy initially worked on a variant of the US Army Jupiter intermediate-range ballistic missile, projecting four of the large. Red Raborn headed a Special Project Office to develop Jupiter for the Navy, soon Chief of Naval Operations Admiral Arleigh Burke concentrated all Navy strategic research on Polaris, still under Admiral Raborns Special Project Office. All US SLBMs have been solid-fueled while all Soviet and Russian SLBMs have been liquid-fueled except for the Russian RSM-56 Bulava, george Washington also conducted the first successful submerged SLBM launch with a Polaris A-1 on 20 July 1960. The Soviets were only a year behind the US with their first SSBN, however, the Hotel class carried only three R-13 missiles each and had to surface and raise the missile to launch. Submerged launch was not an operational capability for the Soviets until 1963, the Soviet Union was able to beat the U. S. The United States eventually conducted a similar test in the Pacific Ocean on 6 May 1962, the first Soviet SSBN with 16 missiles was the Project 667A, which first entered service in 1967 with 32 boats completed by 1974. By the time the first Yankee was commissioned the US had built 41 SSBNs, the short range of the early SLBMs dictated basing and deployment locations. By the late 1960s the Polaris A-3 was deployed on all US SSBNs with a range of 4,600 kilometres, the A-3 also had three warheads that landed in a pattern around a single target. The Yankee class was equipped with the R-27 Zyb missile with a range of 2,400 kilometres. The US was much more fortunate in its basing arrangements than the Soviets, the SSBN facilities at the Advanced Refit Sites were austere, with only a submarine tender and floating dry dock. Converted merchant ships designated T-AKs were provided to ferry missiles and supplies to the sites, with two rotating crews per boat, about one-third of the total US force could be in a patrol area at any time. These missiles were the R-29 Vysota series, equipped on Projects 667B, 667BD, 667BDR, the SS-N-8, with a range of 7,700 kilometres, entered service on the first Delta-I boat in 1972, before the Yankee class was even completed
4.
Multiple independently targetable reentry vehicle
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A multiple independently targetable reentry vehicle is a ballistic missile payload containing several warheads, each capable of being aimed to hit one of a group of targets. By contrast a unitary warhead is a single warhead on a single missile, an intermediate case is the multiple reentry vehicle missile which carries several warheads which are dispersed but not individually aimed. Only the United States, United Kingdom, Russia, France, the military purpose of a MIRV is fourfold, Enhance first-strike proficiency for strategic forces. Providing greater target damage for a given thermonuclear weapon payload, several small warheads cause much more target damage area than a single warhead alone. This in turn reduces the number of missiles and launch facilities required for a destruction level - much the same as the purpose of a cluster munition. With single warhead missiles, one missile must be launched for each target, by contrast with a MIRV warhead, the post-boost stage can dispense the warheads against multiple targets across a broad area. Reduces the effectiveness of a missile system that relies on intercepting individual warheads. While a MIRV attacking missile can have multiple warheads, interceptors may have only one warhead per missile, decoy reentry vehicles can be used alongside actual warheads to minimize the chances of the actual warheads being intercepted before they reach their targets. A system that destroys the missile earlier in its trajectory is not affected by this but is more difficult, MIRV land-based ICBMs were considered destabilizing because they tended to put a premium on striking first. Later on the US feared the Soviets MIRVs because Soviet missiles had a greater throw-weight, for example, the US MIRVs might have increased their warhead per missile count by a factor of 6 while the Soviets increased theirs by a factor of 10. Furthermore, the US had a smaller proportion of its nuclear arsenal in ICBMs than the Soviets. Bombers could not be outfitted with MIRVs so their capacity would not be multiplied, thus the US did not seem to have as much potential for MIRV usage as the Soviets. However, the US had a number of Submarine-launched ballistic missiles, which could be outfitted with MIRVs. It is because of their first-strike capability that land-based MIRVs were banned under the START II agreement, START II was ratified by the Russian Duma on 14 April 2000, but Russia withdrew from the treaty in 2002 after the US withdrew from the ABM treaty. In a MIRV, the rocket motor pushes a bus into a free-flight suborbital ballistic flight path. After the boost phase the bus maneuvers using small on-board rocket motors and it takes up a ballistic trajectory that will deliver a reentry vehicle containing a warhead to a target, and then releases a warhead on that trajectory. It then maneuvers to a different trajectory, releasing another warhead, the precise technical details are closely guarded military secrets, to hinder any development of enemy counter-measures. The bus on-board propellant limits the distances between targets of individual warheads to perhaps a few hundred kilometers, some warheads may use small hypersonic airfoils during the descent to gain additional cross-range distance
5.
Thermonuclear weapon
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A thermonuclear weapon is a nuclear weapon that uses the energy from a primary nuclear fission reaction to compress and ignite a secondary nuclear fusion reaction. The result is greatly increased power when compared to single-stage fission weapons. It is colloquially referred to as a bomb or an H-bomb because it employs the fusion of isotopes of hydrogen. The first full scale thermonuclear test was carried out by the United States in 1952, similar devices were developed by the Soviet Union, United Kingdom, China, and France. The radiation implosion mechanism is an engine that exploits the temperature difference between the secondary stages hot, surrounding radiation channel and its relatively cool interior. This temperature difference is maintained by a massive heat barrier called the pusher. If made of uranium, as is almost always the case, it can capture neutrons produced by the reaction and undergo fission itself. In many Teller–Ulam weapons, fission of the pusher dominates the explosion, detailed knowledge of fission and fusion weapons is classified to some degree in virtually every industrialized nation. Born secret is rarely invoked for cases of private speculation, in a small number of prior cases, the U. S. government has attempted to censor weapons information in the public press, with limited success. According to the New York Times, physicist Kenneth Ford defied government orders to remove classified information from his new book, Building the H Bomb, the state of public knowledge about the Teller–Ulam design has been mostly shaped from a few specific incidents outlined in a section below. At a bare minimum, this implies a primary section consists of an implosion-type fission bomb. The energy released by the primary compresses the secondary through a process called radiation implosion, at which point it is heated, surrounding the other components is a hohlraum or radiation case, a container that traps the first stage or primarys energy inside temporarily. The outside of this case, which is also normally the outside casing of the bomb, is the only direct visual evidence publicly available of any thermonuclear bomb components configuration. Numerous photographs of various thermonuclear bomb exteriors have been declassified, generally, a research program with the capacity to create a thermonuclear bomb has already mastered the ability to engineer boosted fission. The secondary is usually shown as a column of fusion fuel, around the column is first a pusher-tamper, a heavy layer of uranium-238 or lead that serves to help compress the fusion fuel. Inside this is the fuel itself, usually a form of lithium deuteride. This dry fuel, when bombarded by neutrons, produces tritium, inside the layer of fuel is the spark plug, a hollow column of fissile material that, when compressed, can itself undergo nuclear fission. The tertiary, if one is present, would be set below the secondary, separating the secondary from the primary is the interstage
6.
Nuclear submarine
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A nuclear submarine is a submarine powered by a nuclear reactor. The performance advantages of nuclear submarines over conventional submarines are considerable, Nuclear propulsion, being completely independent of air, frees the submarine from the need to surface frequently, as is necessary for conventional submarines. Current generations of nuclear submarines never need to be refueled throughout their 25-year lifespans, the high cost of nuclear technology means that relatively few states have fielded nuclear submarines. Some of the most serious nuclear and radiation accidents ever to occur have involved Soviet nuclear submarine mishaps, the idea for a nuclear-powered submarine was first proposed in the United States Navy by the Naval Research Laboratorys Ross Gunn in 1939. In July 1951 the U. S. Congress authorized construction of the first nuclear-powered submarine, Nautilus, under the leadership of Captain Hyman G. Rickover, the Westinghouse Corporation was assigned to build its reactor. On 17 January 1955, she departed Groton, Connecticut to begin sea trials, the submarine was 320 feet long, and cost about $55 million. The Soviet Union soon followed the United States in developing nuclear-powered submarines in the 1950s, in 1956, the first Soviet propulsion reactor designed by his team began operational testing. Meanwhile, a team under Vladimir N. Peregudov worked on the vessel that would house the reactor. Nuclear power proved ideal for the propulsion of strategic ballistic missile submarines, the Soviets already had several SSBs of the Project 629, and were only a year behind the US with their first SSBN, the ill-fated K-19 of Project 658, commissioned in November 1960. However, this carried the same three-missile armament as the Golfs. The first Soviet SSBN with 16 missiles was the Project 667A, at the height of the Cold War, approximately five to ten nuclear submarines were being commissioned from each of the four Soviet submarine yards. From the late 1950s through the end of 1997, the Soviet Union, today, six countries deploy some form of nuclear-powered strategic submarines, the United States, Russia, France, the United Kingdom, China, and India. Several other countries, including Argentina and Brazil, have ongoing projects in different phases to build nuclear-powered submarines, in the United Kingdom, all former and current nuclear submarines of the British Royal Navy have been constructed in Barrow-in-Furness where construction of nuclear submarines continues. Conqueror is the only nuclear-powered submarine ever to have engaged an enemy ship with torpedoes, the main difference between conventional submarines and nuclear submarines is the power generation system. Nuclear submarines employ nuclear reactors for this task and they either generate electricity that powers electric motors connected to the propeller shaft or rely on the reactor heat to produce steam that drives steam turbines. All naval nuclear reactors currently in use are operated with diesel generators as a power system. These engines are able to provide electrical power for reactor decay heat removal. Submarines may carry nuclear fuel for up to 30 years of operation, the only resource that limits the time underwater is the food supply for the crew and maintenance of the vessel
7.
Ballistic missile submarine
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A ballistic missile submarine is a submarine deploying submarine-launched ballistic missiles with nuclear warheads. These submarines became a weapon system in the Cold War because of their nuclear deterrence capability. Their deployment has been dominated by the United States and the Soviet Union / Russia, with numbers in service with France, the United Kingdom, China. This submarine launched the worlds first SLBM, an R-11FM on 16 September 1955, five additional Project V611 and AV611 submarines became the worlds first operational SSBs with two R-11FM missiles each, entering service in 1956-57. They were followed by a series of 23 specifically designed Project 629 SSBs completed 1958-62, the Polaris missile and the first US SSBNs were developed by a Special Project office under Rear Admiral W. F. Red Raborn, appointed by Chief of Naval Operations Admiral Arleigh Burke, George Washington was redesigned and rebuilt early in construction from a Skipjack-class fast attack submarine, USS Scorpion, with a 130 ft missile compartment welded into the middle. Nuclear power was an advance, allowing a ballistic missile submarine to remain undetected at sea by remaining submerged or occasionally at periscope depth for an entire patrol. With more missiles on one US SSBN than on five Golf-class boats, the Soviets were only a year behind the US with their first SSBN, the ill-fated K-19 of Project 658, commissioned in November 1960. However, this carried the same three-missile armament as the Golfs. The first Soviet SSBN with 16 missiles was the Project 667A, the short range of the early SLBMs dictated basing and deployment locations. By the late 1960s the Polaris A-3 was deployed on all US SSBNs with a range of 4,600 kilometres, the A-3 also had three warheads that landed in a pattern around a single target. The Yankee class was equipped with the R-27 Zyb missile with a range of 2,400 kilometres. The US was much more fortunate in its basing arrangements than the Soviets, with two rotating crews per SSBN, about one-third of the total US force could be in a patrol area at any time. These missiles were the R-29 Vysota series, equipped on Projects 667B, 667BD, 667BDR, the SS-N-8, with a range of 7,700 kilometres, entered service on the first Delta-I boat in 1972, before the Yankee class was even completed. A total of 43 Delta-class boats of all entered service 1972-90, with the SS-N-18 on the Delta III class. The new missiles had increased range and eventually Multiple Independently-targeted Re-entry Vehicles, the Delta-I class had 12 missiles each, the others have 16 missiles each. All Deltas have a superstructure to accommodate their large liquid-fueled missiles. Although the US did not commission any new SSBNs from 1967 through 1981, thirty-one of the 41 original US SSBNs were built with larger diameter launch tubes with future missiles in mind
8.
United States Navy
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The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U. S. Navy is the largest, most capable navy in the world, the U. S. Navy has the worlds largest aircraft carrier fleet, with ten in service, two in the reserve fleet, and three new carriers under construction. The service has 323,792 personnel on duty and 108,515 in the Navy Reserve. It has 274 deployable combat vessels and more than 3,700 operational aircraft as of October 2016, the U. S. Navy traces its origins to the Continental Navy, which was established during the American Revolutionary War and was effectively disbanded as a separate entity shortly thereafter. It played a role in the American Civil War by blockading the Confederacy. It played the role in the World War II defeat of Imperial Japan. The 21st century U. S. Navy maintains a global presence, deploying in strength in such areas as the Western Pacific, the Mediterranean. The Navy is administratively managed by the Department of the Navy, the Department of the Navy is itself a division of the Department of Defense, which is headed by the Secretary of Defense. The Chief of Naval Operations is an admiral and the senior naval officer of the Department of the Navy. The CNO may not be the highest ranking officer in the armed forces if the Chairman or the Vice Chairman of the Joint Chiefs of Staff. The mission of the Navy is to maintain, train and equip combat-ready Naval forces capable of winning wars, deterring aggression, the United States Navy is a seaborne branch of the military of the United States. The Navys three primary areas of responsibility, The preparation of naval forces necessary for the prosecution of war. The development of aircraft, weapons, tactics, technique, organization, U. S. Navy training manuals state that the mission of the U. S. Armed Forces is to prepare and conduct prompt and sustained combat operations in support of the national interest, as part of that establishment, the U. S. Navys functions comprise sea control, power projection and nuclear deterrence, in addition to sealift duties. It follows then as certain as that night succeeds the day, that without a decisive naval force we can do nothing definitive, the Navy was rooted in the colonial seafaring tradition, which produced a large community of sailors, captains, and shipbuilders. In the early stages of the American Revolutionary War, Massachusetts had its own Massachusetts Naval Militia, the establishment of a national navy was an issue of debate among the members of the Second Continental Congress. Supporters argued that a navy would protect shipping, defend the coast, detractors countered that challenging the British Royal Navy, then the worlds preeminent naval power, was a foolish undertaking. Commander in Chief George Washington resolved the debate when he commissioned the ocean-going schooner USS Hannah to interdict British merchant ships, and reported the captures to the Congress
9.
Ohio-class submarine
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The Ohio class is a class of nuclear-powered submarines currently used by the United States Navy. The navy has 18 Ohio-class submarines,14 ballistic missile submarines, the Ohio class was named after the lead submarine of this class, USS Ohio. The 14 Trident II SSBNs together carry approximately fifty percent of the total US active inventory of strategic thermonuclear warheads. All the Ohio-class submarines, except for USS Henry M. Jackson, are named for U. S. states, the Ohio-class submarines are the largest submarines ever built for the U. S. Navy. The Ohio-class submarines were designed specifically for extended war-deterrence patrols, each of these submarines is provided with two complete crews, called the Blue crew and the Gold crew, with each crew serving typically on 70- to 90-day deterrent patrols. To decrease the time in port for crew turnover and replenishment, the classs design allows the warship to operate for about fifteen years between major overhauls. These submarines are reported to be as quiet at their speed of 20 knots or more than the previous Lafayette-class submarines at 6 knots. Fire control for their Mark 48 torpedoes is carried out by Mark 118 Mod 2 system, the Ohio-class submarines were constructed from sections of hull, with each four-deck section being 42 ft in diameter. The sections were produced at the General Dynamics Electric Boat facility, Quonset Point, Rhode Island, the US Navy has a total of 18 Ohio-class submarines which consist of 14 ballistic missile submarines, and four cruise missile submarines. The SSBN submarines are known as Trident submarines, and provide the sea-based leg of the U. S. nuclear triad. Each SSBN submarine is armed with up to 24 Trident II submarine-launched ballistic missiles, each SSGN is capable of carrying 154 Tomahawk cruise missiles, plus a complement of Harpoon missiles to be fired through their torpedo tubes. The first eight Ohio-class submarines were armed at first with 24 Trident I C4 SLBMs, beginning with the ninth Trident submarine, Tennessee, the remaining boats were equipped with the larger, three-stage Trident II D5 missile. Starting with Alaska in 2000, the Navy began converting its remaining ballistic missile submarines armed with C4 missiles to carry D5 missiles and this task was completed in mid-2008. The first eight submarines had their home ports at Bangor, Washington, the remaining ten submarines originally had their home ports at Kings Bay, Georgia, replacing the Poseidon and Trident Backfit submarines of the Atlantic Fleet. During the conversion of the first four submarines to SSGNs, five of the submarines, Pennsylvania, Kentucky, Nebraska, Maine, further transfers occur as the strategic weapons goals of the United States change. In 2011, Ohio-class submarines carried out 28 deterrent patrols, each patrol lasts around 70 days. Four boats are on station in designated areas at any given time. From January to June 2014, Pennsylvania carried out a 140-day-long patrol, after the end of the Cold War, plans called for Ohio to be retired in 2002, followed by three of her sister boats
10.
Royal Navy
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The Royal Navy is the United Kingdoms naval warfare force. Although warships were used by the English kings from the medieval period. The modern Royal Navy traces its origins to the early 16th century, from the middle decades of the 17th century and through the 18th century, the Royal Navy vied with the Dutch Navy and later with the French Navy for maritime supremacy. From the mid 18th century it was the worlds most powerful navy until surpassed by the United States Navy during the Second World War. The Royal Navy played a key part in establishing the British Empire as the world power during the 19th. Due to this historical prominence, it is common, even among non-Britons, following World War I, the Royal Navy was significantly reduced in size, although at the onset of the Second World War it was still the worlds largest. By the end of the war, however, the United States Navy had emerged as the worlds largest, during the Cold War, the Royal Navy transformed into a primarily anti-submarine force, hunting for Soviet submarines, mostly active in the GIUK gap. The Royal Navy is part of Her Majestys Naval Service, which includes the Royal Marines. The professional head of the Naval Service is the First Sea Lord, the Defence Council delegates management of the Naval Service to the Admiralty Board, chaired by the Secretary of State for Defence. The strength of the fleet of the Kingdom of England was an important element in the power in the 10th century. English naval power declined as a result of the Norman conquest. Medieval fleets, in England as elsewhere, were almost entirely composed of merchant ships enlisted into service in time of war. Englands naval organisation was haphazard and the mobilisation of fleets when war broke out was slow, early in the war French plans for an invasion of England failed when Edward III of England destroyed the French fleet in the Battle of Sluys in 1340. Major fighting was confined to French soil and Englands naval capabilities sufficed to transport armies and supplies safely to their continental destinations. Such raids halted finally only with the occupation of northern France by Henry V. Henry VII deserves a large share of credit in the establishment of a standing navy and he embarked on a program of building ships larger than heretofore. He also invested in dockyards, and commissioned the oldest surviving dry dock in 1495 at Portsmouth, a standing Navy Royal, with its own secretariat, dockyards and a permanent core of purpose-built warships, emerged during the reign of Henry VIII. Under Elizabeth I England became involved in a war with Spain, the new regimes introduction of Navigation Acts, providing that all merchant shipping to and from England or her colonies should be carried out by English ships, led to war with the Dutch Republic. In the early stages of this First Anglo-Dutch War, the superiority of the large, heavily armed English ships was offset by superior Dutch tactical organisation and the fighting was inconclusive
11.
Vanguard-class submarine
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The Vanguard class is a class of nuclear-powered ballistic missile submarines in service with the Royal Navy. The class was introduced in 1994 as part of the Trident nuclear programme and they were built between 1986 and 1999 at Barrow-in-Furness by Vickers Shipbuilding and Engineering, which is now owned by BAE Systems. All four boats are based at HM Naval Base Clyde,40 km west of Glasgow, since the decommissioning of the Royal Air Force WE.177 free-fall thermonuclear weapons in 1998, the four Vanguard submarines are the sole platforms for the United Kingdoms nuclear weapons. Each submarine is armed with up to 16 UGM-133 Trident II missiles, the class is scheduled to be replaced starting 2028, though its replacement would not enter service until early 2030s. Beginning in the late 1960s, the United Kingdom operated four Resolution-class submarines, the Polaris missile was supplied to Britain following the terms of the 1963 Polaris Sales Agreement. This nuclear deterrent system was known as the UK Polaris programme, on the 24 January 1980, the House of Commons backed government policy, by 308 votes to 52, to retain an independent nuclear deterrent. Options that were examined included, A British designed and built ballistic missile, Although Britain had no capability in this field since the 1960s, it was considered to not be impossible. However, it would come at the cost of being expensive, would be full of uncertainty. Thus the option was considered unattractive, retain Polaris, but fitted on a new submarine class, This option would have a cheaper initial capital cost, but would lack in terms of required capability and reliability. Also, it was concluded that any initial capital savings would have been lost beyond the 1990s, a European solution and the US UGM-73 Poseidon were also briefly considered, but ultimately rejected, primarily on capability, cost and uncertainty grounds. An agreement was made in March 1982 between the two countries, and under the agreement, Britain made a 5% research and development contribution. Beginning in 1985, both HMNB Clyde and the Royal Naval Armaments Depot Coulport at Faslane underwent extensive redevelopment in preparation for the Vanguard class submarines, rosyth dockyard also underwent significant redevelopment. The work included enhanced handling, storage, armament processing, berthing, docking, engineering, training and refitting facilities at an estimates cost of £550 million. Similarly, due to the scale of the Vanguard-class design. Construction started in 1982 and was completed in 1986, the Vanguard class were designed in the early 1980s by Vickers Shipbuilding and Engineering based at Barrow-in-Furness, now BAE Systems Maritime – Submarines. They were designed from the outset as nuclear-powered ballistic missile submarines, as such, the missile compartment is based on the same system used on the American Ohio class, which is also equipped with the UGM-133 Trident II. Thatcher laid the keel of the first boat, HMS Vanguard, Vanguard was launched in 1992 and commissioned in 1993. 1992 saw a debate whether the fourth vessel, Vengeance, should be cancelled
12.
Trident of Poseidon
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The trident of Poseidon and his Roman equivalent, Neptune, has been their traditional divine attribute featured in many ancient depictions. In Hesiods account, Poseidons trident was crafted by the three Cyclopes, in another view shared by Friedrich Wieseler, E. M. W. Tillyard and several other researchers, Poseidons trident is a fish spear, typical for coast-dwelling Greeks. In that sense it resembles the arrow-headed pronged fork, used by the Mediterranean fishermen to catch eels, Poseidon became particularly worshipped in coastal countries, where fish formed a basic commodity of trade. According to competing proposal by H. B, walters, Poseidons trident is derived from Zeus lotus sceptre, with Poseidon being Zeus in his marine aspect. In Greek myths, Poseidon wields his trident on a number of occasions, during the contest with Athena over the possession of Attica Poseidon strikes the Acropolis with the trident to produce a well of seawater. In a similar myth Poseidon strikes the ground with trident to produce a horse for mankind, the oldest coins of Poseidonia from the 6th century BC depict trident wielded by Poseidon in his right hand, similar to Zeuss thunderbolt. An Attic red figure kylix from c. 475 BC depicts Poseidon killing the Giant Polybotes with his trident, in another myth, Poseidon creates a spring or springs with the strike of his trident to reward Amymone for her encounter with him. In a version of another myth Poseidon wields his trident to scare off a satyr who tries to rape Amymone after she hits him with a hunting spear. There is also a myth where Poseidon touches the island of Delos with his trident, another myth tells how Poseidon, enraged by sacrilegious behavior of Ajax the Lesser, splits with trident the rock to which Ajax was clinging. According to the second and third Vatican Mythographer, Neptunes trident symbolizes the three properties of water, liquidity, fecundity and drinkability, a series of American fleet ballistic missiles Trident is named after Neptunes trident, as well as Operation Neptune Spear. The personification of Great Britain, Britannia is depicted with the trident of Poseidon as a symbol of naval power, the logo of car manufacturer Maserati is based on the trident from the statue of Neptune in Bologna. The trident of Poseidon is an artifact with destructive powers in Michael Livingstons 2015 historical fantasy novel The Shards of Heaven
13.
Polaris Sales Agreement
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The Polaris Sales Agreement was an agreement between the United States and the United Kingdom which began the UK Polaris programme. The agreement formally arranged for the Polaris missile system to be provided to the UK, the arrangement had been set up in principle as a result of the Nassau Agreement. The agreement was amended in 1982 to provide the Trident missile system to the UK, the United Kingdom had been planning to buy the air-launched Skybolt missile but the USA decided to cancel the Skybolt program in 1962 as they no longer needed the missile. The British bought the Polaris submarine-launched ballistic missile instead, the Nassau Agreement was signed on December 18,1962 resulting in the signing of the Polaris Sales Agreement on April 6,1963. The United States would supply the United Kingdom with Polaris missiles, launch tubes, the UK would make the warheads and submarines. In return, the U. S. was given assurances by the United Kingdom regarding the use of the missile. The British Polaris submarines were the Resolution-class ballistic missile submarines, the first of which entered service in 1968, the Polaris system underwent a British-designed life extension programme called Chevaline that reduced the number of warheads and added defensive measures. The Polaris Sales Agreement was used as the model for the UKs purchase of the Trident weapon system to replace Polaris in British service. The arrangements were almost identical to that for Polaris, the United Kingdom procured the Trident system from America and fitted them to their own submarines, HMS Vanguard entered operational service in December 1994. British Prime Minister Margaret Thatcher had written to President Carter on July 10,1980 to request that he approve supply of Trident I missiles. However, in 1982 Thatcher wrote to President Reagan to request the United Kingdom be allowed to procure the Trident II system and this was agreed in March 1982. Under the Polaris Sales Agreement, the United Kingdom paid a 5% levy on the cost of equipment supplied in recognition of US research, the R&D contribution to Trident comprised payments amounting to $116M with no on-going R&D levy. U. S. suppliers are paid via the U. S. based Polaris Trust Fund, British replacement of the Trident system Nuclear weapons and the United Kingdom 1958 US-UK Mutual Defence Agreement
14.
Margaret Thatcher
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She was the longest-serving British prime minister of the 20th century, and the first woman to have held the office. A Soviet journalist dubbed her The Iron Lady, a nickname that became associated with her uncompromising politics, as Prime Minister, she implemented policies that have come to be known as Thatcherism. A research chemist before becoming a barrister, Thatcher was elected Member of Parliament for Finchley in 1959, Edward Heath appointed her Secretary of State for Education and Science in his 1970 government. In 1975, Thatcher defeated Heath in the Conservative Party leadership election to become Leader of the Opposition and she became Prime Minister after winning the 1979 general election. Her political philosophy and economic policies emphasised deregulation, flexible labour markets, the privatisation of state-owned companies and she narrowly escaped an assassination attempt in 1984. Thatcher was re-elected for a term in 1987. During this period her support for a Community Charge was widely unpopular and she resigned as Prime Minister and party leader in November 1990, after Michael Heseltine launched a challenge to her leadership. After retiring from the Commons in 1992, she was given a peerage as Baroness Thatcher which entitled her to sit in the House of Lords. After a series of strokes in 2002, she was advised to withdraw from public speaking. Despite this, she managed to pre-record a eulogy to Ronald Reagan prior to his death, in 2013, she died of another stroke in London, at the age of 87. Always a controversial figure, she has described as one of the greatest and most influential politicians in British history. Thatcher was born Margaret Hilda Roberts on 13 October 1925, in Grantham and her father was Alfred Roberts, originally from Northamptonshire, and her mother was Beatrice Ethel from Lincolnshire. She spent her childhood in Grantham, where her father owned two grocery shops, Prior to the Second World War, in 1938 the Roberts family gave sanctuary to a teenage Jewish girl escaping Nazi Germany. Thatcher was to describe this in her memoirs as among the significant events of her formative years, Alfred Roberts was an alderman and a Methodist local preacher, and brought up his daughter as a strict Wesleyan Methodist attending the Finkin Street Methodist Church. He came from a Liberal family but stood as an Independent and he was Mayor of Grantham in 1945–46 and lost his position as alderman in 1952 after the Labour Party won its first majority on Grantham Council in 1950. Margaret Roberts attended Huntingtower Road Primary School and won a scholarship to Kesteven and her school reports showed hard work and continual improvement, her extracurricular activities included the piano, field hockey, poetry recitals, swimming and walking. She was head girl in 1942–43, in her upper sixth year she applied for a scholarship to study chemistry at Somerville College, Oxford, but she was initially rejected and was offered a place only after another candidate withdrew. Her dissertation was on the structure of the antibiotic gramicidin, even while working on chemistry, she was already thinking towards law and politics
15.
Jimmy Carter
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James Earl Jimmy Carter Jr. is an American politician who served as the 39th President of the United States from 1977 to 1981. In 2002, he was awarded the Nobel Peace Prize for his work with the Carter Center, Carter was a Democrat who was raised in rural Georgia. He was a farmer who served two terms as a Georgia State Senator from 1963 to 1967, and one as the Governor of Georgia from 1971 to 1975. He was elected President in 1976, defeating incumbent President Gerald Ford in a close election. On his second day in office, Carter pardoned all evaders of the Vietnam War drafts, during Carters term as President, two new cabinet-level departments, the Department of Energy and the Department of Education, were established. He established an energy policy that included conservation, price control. In foreign affairs, Carter pursued the Camp David Accords, the Panama Canal Treaties, the round of Strategic Arms Limitation Talks. On the economic front he confronted persistent stagflation, a combination of inflation, high unemployment. The end of his tenure was marked by the 1979–1981 Iran hostage crisis, the 1979 energy crisis, the Three Mile Island nuclear accident. In response to the Soviet move he ended détente, escalated the Cold War, Carter won the 1980 primary with 51. 13% of the vote but lost the general election in an electoral landslide to Republican nominee Ronald Reagan, who won 44 of 50 states. His presidency has drawn medium-low responses from historians, with many considering him to have accomplished more with his post-presidency work and he set up the Carter Center in 1982 as his base for advancing human rights. He has also traveled extensively to conduct negotiations, observe elections. Additionally, Carter is a key figure in the Habitat for Humanity project, since surpassing Herbert Hoover in September 2012, he has been the longest-retired president in American history. He is also the first president to mark the 40th anniversary of his election and inauguration, in reference to current political views, he has criticized some of Israels actions and policies in regards to the Israeli–Palestinian conflict and has advocated for a two-state solution. James Earl Carter, Jr. was born on October 1,1924, at the Wise Sanitarium in Plains and he is a descendant of English immigrant Thomas Carter, who settled in Virginia in 1635. Numerous generations of Carters lived as farmers in Georgia. Carter is also a descendant of Thomas Cornell, an ancestor of Cornell Universitys founder and of Richard Nixon, Plains was a boomtown of 600 people at the time of Carters birth. His father, James Earl Carter, Sr. was a local businessman who ran a general store and had begun to invest in farmland
16.
Ronald Reagan
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Ronald Wilson Reagan was an American politician and actor who was the 40th President of the United States, from 1981 to 1989. Before his presidency, he was the 33rd Governor of California, from 1967 to 1975, after a career as a Hollywood actor and union leader. Raised in a family in small towns of northern Illinois, Reagan graduated from Eureka College in 1932. After moving to Hollywood in 1937, he became an actor, Reagan was twice elected President of the Screen Actors Guild, the labor union for actors, where he worked to root out Communist influence. In the 1950s, he moved into television and was a speaker at General Electric factories. Having been a lifelong Democrat, his views changed and he became a conservative and in 1962 switched to the Republican Party. In 1964, Reagans speech, A Time for Choosing, in support of Barry Goldwaters foundering presidential campaign, Building a network of supporters, he was elected Governor of California in 1966. Entering the presidency in 1981, Reagan implemented sweeping new political, in his first term he survived an assassination attempt, spurred the War on Drugs, and fought public sector labor. During his re-election bid, Reagan campaigned on the notion that it was Morning in America, foreign affairs dominated his second term, including ending of the Cold War, the bombing of Libya, and the Iran–Contra affair. Publicly describing the Soviet Union as an empire, and during his famous speech at the Brandenburg Gate. Jack, a salesman and storyteller, was the grandson of Irish Catholic immigrants from County Tipperary, Reagan had one older brother, John Neil Reagan, who became an advertising executive. As a boy, Reagans father nicknamed his son Dutch, due to his fat little Dutchman-like appearance and Dutchboy haircut, Reagans family briefly lived in several towns and cities in Illinois, including Monmouth, Galesburg, and Chicago. In 1919, they returned to Tampico and lived above the H. C, Pitney Variety Store until finally settling in Dixon. After his election as president, residing in the upstairs White House private quarters, for the time, Reagan was unusual in his opposition to racial discrimination, and recalled a time in Dixon when the local inn would not allow black people to stay there. Reagan brought them back to his house, where his mother invited them to stay the night and have breakfast the next morning, after the closure of the Pitney Store in late 1920 and the familys move to Dixon, the midwestern small universe had a lasting impression on Reagan. Reagan attended Dixon High School, where he developed interests in acting, sports and his first job was as a lifeguard at the Rock River in Lowell Park in 1927. Over a six-year period, Reagan reportedly performed 77 rescues as a lifeguard and he attended Eureka College, a Disciples-oriented liberal arts school, where he became a member of the Tau Kappa Epsilon fraternity, a cheerleader, and studied economics and sociology. While involved, the Miller Center of Public Affairs described him as an indifferent student and he majored in economics and sociology, and graduated with a C grade
17.
Lockheed Martin
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Lockheed Martin is an American global aerospace, defense, security and advanced technologies company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995 and it is headquartered in Bethesda, Maryland, in the Washington, DC, area. Lockheed Martin employs 126,000 people worldwide, Marillyn Hewson is the current President and Chief Executive Officer. Lockheed Martin is one of the largest companies in the aerospace, defense, security and it is the worlds largest defense contractor based on revenue for fiscal year 2014. In 2013, 78% of Lockheed Martins revenues came from sales, it topped the list of US federal government contractors. In 2009 US government contracts accounted for $38.4 billion, foreign government contracts $5.8 billion, Lockheed Martin operates in five business segments, Aeronautics, Information Systems & Global Solutions, Missiles and Fire Control, Rotary and Mission Systems, and Space Systems. The company also invests in healthcare systems, renewable energy systems, intelligent energy distribution, merger talks between Lockheed Corporation and Martin Marietta began in March 1994, with the companies announcing their $10 billion planned merger on August 30,1994. The deal was finalized on March 15,1995, when the two companies approved the merger. The segments of the two companies not retained by the new company formed the basis for the present L-3 Communications, Lockheed Martin also later spun off the materials company Martin Marietta Materials. Both companies contributed important products to the new portfolio, Lockheed products included the Trident missile, P-3 Orion, F-16 Fighting Falcon, F-22 Raptor, C-130 Hercules, A-4AR Fightinghawk and the DSCS-3 satellite. Martin Marietta products included Titan rockets, Sandia National Laboratories, Space Shuttle External Tank, Viking 1 and Viking 2 landers, the Transfer Orbit Stage and various satellite models. On April 22,1996, Lockheed Martin completed the acquisition of Loral Corporations defense electronics and system integration businesses for $9.1 billion, the remainder of Loral became Loral Space & Communications. Lockheed Martin abandoned plans for a $8, the development of the spacecraft cost $193.1 million. In May 2001, Lockheed Martin sold Lockheed Martin Control Systems to BAE Systems, on November 27,2000, Lockheed completed the sale of its Aerospace Electronic Systems business to BAE Systems for $1.67 billion, a deal announced in July 2000. This group encompassed Sanders Associates, Fairchild Systems, and Lockheed Martin Space Electronics & Communications. In 2001, Lockheed Martin won the contract to build the F-35 Lightning II, in 2001, Lockheed Martin settled a nine–year investigation conducted by NASAs Office of Inspector General with the assistance of the Defense Contract Audit Agency. The company paid the United States government $7.1 million based on allegations that its predecessor, Lockheed Engineering Science Corporation, submitted false lease costs claims to NASA. On August 31,2006, Lockheed Martin won a $3.9 billion contract from NASA to design and build the CEV capsule, in 2009, NASA reduced the capsule crew requirements from the initial six seats to four for transport to the International Space Station
18.
Tony Blair
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Anthony Charles Lynton Blair is a British politician who served as the Prime Minister of the United Kingdom from 1997 to 2007 and the Leader of the Labour Party from 1994 to 2007. From 1983 to 2007, Blair was the MP for Sedgefield, under Blairs leadership, the party used the phrase New Labour, to distance it from previous Labour policies and the traditional conception of socialism. Critics of Blair denounced him for having the Labour Party abandon genuine socialism, in May 1997, the Labour Party won a landslide general election victory, the largest in its history, allowing Blair, at 43 years old, to become the youngest Prime Minister since 1812. In September 1997, Blair attained early personal popularity, receiving a 93% public approval rating, the Labour Party went on to win two more elections under his leadership, in 2001, in which it won another landslide victory, and in 2005, with a reduced majority. In the first years of the New Labour government, Blairs government introduced the National Minimum Wage Act, Human Rights Act, Blairs government also devolved power, establishing the Scottish Parliament, the National Assembly for Wales, and the Northern Ireland Assembly. In Northern Ireland, Blair was involved in the 1998 Good Friday Agreement, Blair has faced strong criticism for his role in the invasion of Iraq, including calls for having him tried for war crimes and waging a war of aggression. In 2016, the Iraq Inquiry strongly criticised his actions and described the invasion of Iraq as unjustified, Blair also intervened militarily in Kosovo and Sierra Leone. Blair was succeeded as the leader of the Labour Party and as Prime Minister by Gordon Brown in June 2007. On the day that Blair resigned as Prime Minister, he was appointed the official Special Envoy of the Quartet on the Middle East and he now runs a consultancy business and has set up various foundations in his own name, including the Tony Blair Faith Foundation. Anthony Charles Lynton Blair was born in Edinburgh, Scotland, on 6 May 1953 and he was the second son of Leo and Hazel Blair. Leo Blair was the son of two entertainers and adopted as a baby by Glasgow shipyard worker James Blair and his wife. Hazel Corscadden was the daughter of George Corscadden, a butcher, in 1923 he returned to Ballyshannon, County Donegal. In Ballyshannon Corscaddens wife, Sarah Margaret, gave birth above the grocery shop to Blairs mother. Blair has one brother, Sir William Blair, a High Court judge. Blairs first home was with his family at Paisley Terrace in the Willowbrae area of Edinburgh, during this period, his father worked as a junior tax inspector whilst also studying for a law degree from the University of Edinburgh. Blairs first relocation was when he was 19 months old, at the end of 1954 Blairs parents and their two sons moved from Paisley Terrace to Adelaide, South Australia. His father lectured in law at the University of Adelaide and it was when in Australia that Blairs sister Sarah was born. The Blairs lived in the suburb of Dulwich close to the university, the family returned to the UK in summer 1958
19.
Dreadnought-class submarine
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The Dreadnought class is the replacement for the Vanguard class of ballistic missile submarines which entered service in the United Kingdom in the 1990s with an intended service life of 25 years. They will carry Trident D-5 missiles – the vehicle for delivering the UKs nuclear weapons, replacing the Vanguard submarines is necessary if the Royal Navy is to maintain a continuous at-sea deterrent, the principle of operation behind the Trident system. In May 2011 the government approved the initial assessment phase for the new submarines, in May 2015 the Conservative Party won the UK General Election on a manifesto which included a commitment to maintaining a CASD with four Successor submarines. The final decision to commit to the Successor programme was approved on 18 July 2016 when the House of Commons voted to renew Trident by 472 votes to 117, construction started in late 2016 at the Barrow-in-Furness shipyard operated by BAE Systems Maritime – Submarines. The first submarine is expected to enter service in 2028. Previously named Successor class, it was announced on 21 October 2016 that the first of class would be named Dreadnought. The next three boats will also be given names with historical resonance, since the retirement of the last Royal Air Force WE.177 nuclear bomb in 1998, the British nuclear arsenal has been wholly submarine-based. This is intended to deter an enemy because they cannot ensure eliminating the entire stockpile in a first strike if a ballistic missile submarine remains undetected. Since the Strategic Defence Review, the UK has maintained a stockpile of around 215 warheads, with around 120 active. In a policy known as Continuous at Sea Deterrence, at least one Vanguard-class SSBN is kept on patrol with up to 16 Trident missiles sharing up to 48 warheads from the stockpile at any given time, the SDR considered this was the minimum number of warheads adequate for deterrence. It is collectively known as the Trident system, the majority of this system is based in Scotland at HM Naval Base Clyde, which includes the Faslane home of the Vanguard submarines, and at the Coulport nuclear depot. Since 1998, the system has provided the Government with the option of a lower-yield. The oldest Vanguard-class submarine is expected to remain in service until 2019 without a refit, prompting consideration of a replacement before the end of 2010 to allow for development time
20.
USS Tennessee (SSBN-734)
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USS Tennessee is a United States Navy Ohio-class ballistic missile submarine that has been in commission since 1988. She is the ship and first submarine of the U. S. Navy to be named for Tennessee. Her keel was laid there on 9 June 1986. The Tennessee was the first Ohio-class submarine commissioned capable of launching the Trident II ballistic missile, on 21 March 1989, off the coast of Cape Canaveral, Florida, the Tennessee attempted the first submerged launch of the D5 which failed four seconds into the flight. Once the problem was understood, relatively simple changes were made and this article includes information collected from the Naval Vessel Register, which, as a U. S. government publication, is in the public domain. The entry can be found here, USS Tennessee at GlobalSecurity. org Photo gallery of USS Tennessee at NavSource Naval History
21.
UGM-96 Trident I
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The UGM-96 Trident I, or Trident C4, was an American submarine-launched ballistic missile, built by Lockheed Martin Space Systems in Sunnyvale, California. First deployed in 1979, the Trident I replaced the Poseidon missile and it was retired in 2005, having been replaced by the Trident II. In 1980, the Royal Navy requested Trident I missiles under the Polaris Sales Agreement, in 1982 and it was the first Trident missile to enter service. The Trident I is a three-stage, solid-fuelled missile, the first eight Ohio-class submarines were armed with Trident I missiles. Twelve James Madison- and Benjamin Franklin-class submarines were also retrofitted with Trident I missiles, which replaced older Poseidon missiles
22.
Cape Canaveral Air Force Station
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Cape Canaveral Air Force Station is an installation of the United States Air Force Space Commands 45th Space Wing, headquartered at nearby Patrick Air Force Base. Located on Cape Canaveral in Brevard County, Florida, CCAFS is the primary head of Americas Eastern Range with three launch pads currently active. The Cape Canaveral Air Force Station Skid Strip provides a 10, 000-foot runway close to the launch complexes for military airlift aircraft delivering heavy, a number of American space exploration firsts were launched from CCAFS, including the first U. S. Earth satellite, first U. S. astronaut, first U. S. astronaut in orbit, first two-man U. S. spacecraft, first U. S. unmanned lunar landing, and first three-man U. S. spacecraft. The CCAFS area had used by the United States government to test missiles since 1949. On June 1,1948, the U. S. Navy transferred the former Banana River Naval Air Station to the U. S. Air Force, with USAF renaming the facility the Joint Long Range Proving Ground Base on June 10,1949. On October 1,1949, the Joint Long Range Proving Ground Base was transferred from the Air Materiel Command to the Air Force Division of the Joint Long Range Proving Ground. On May 17,1950, the base was renamed the Long Range Proving Ground Base, in 1951, the Air Force established the Air Force Missile Test Center. Early American sub-orbital rocket flights were achieved at Cape Canaveral in 1956 and these flights occurred shortly after sub-orbital flights launched from White Sands Missile Range, such as the Viking 12 sounding rocket on February 4,1955. Following the Soviet Unions successful Sputnik 1, the US attempted its first launch of a satellite from Cape Canaveral on December 6,1957. However, the rocket carrying Vanguard TV3 blew up on the launch pad, NASA was founded in 1958, and Air Force crews launched missiles for NASA from the Cape, known then as Cape Canaveral Missile Annex. The row of Titan and Atlas launch pads along the coast came to be known as Missile Row in the 1960s, nASAs first manned spaceflight program was prepared for launch from Canaveral by U. S. Air Force crews. Mercurys objectives were to place a spacecraft in Earth orbit, investigate human performance and ability to function in space. Suborbital flights were launched by derivatives of the Armys Redstone missile from LC-5, Orbital flights were launched by derivatives of the Air Forces larger Atlas D missile from LC-14. The first American in orbit was John Glenn on February 20,1962, three more orbital flights followed through May 1963. Flight control for all Mercury missions was provided at the Mercury Control Center located at Canaveral near LC-14 and he had also convinced Gov. C. Farris Bryant to change the name of Cape Canaveral to Cape Kennedy and this resulted in some confusion in public perception, which conflated the two. This name was used through the Gemini and early Apollo programs, however, the geographical name change proved to be unpopular, owing to the historical longevity of Cape Canaveral
23.
Nitrogen
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Nitrogen is a chemical element with symbol N and atomic number 7. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772, although Carl Wilhelm Scheele and Henry Cavendish had independently done so at about the same time, Rutherford is generally accorded the credit because his work was published first. Nitrogen is the lightest member of group 15 of the periodic table, the name comes from the Greek πνίγειν to choke, directly referencing nitrogens asphyxiating properties. It is an element in the universe, estimated at about seventh in total abundance in the Milky Way. At standard temperature and pressure, two atoms of the element bind to form dinitrogen, a colourless and odorless diatomic gas with the formula N2, dinitrogen forms about 78% of Earths atmosphere, making it the most abundant uncombined element. Nitrogen occurs in all organisms, primarily in amino acids, in the nucleic acids, the human body contains about 3% nitrogen by mass, the fourth most abundant element in the body after oxygen, carbon, and hydrogen. The nitrogen cycle describes movement of the element from the air, into the biosphere and organic compounds, many industrially important compounds, such as ammonia, nitric acid, organic nitrates, and cyanides, contain nitrogen. The extremely strong bond in elemental nitrogen, the second strongest bond in any diatomic molecule. Synthetically produced ammonia and nitrates are key industrial fertilisers, and fertiliser nitrates are key pollutants in the eutrophication of water systems. Apart from its use in fertilisers and energy-stores, nitrogen is a constituent of organic compounds as diverse as Kevlar used in high-strength fabric, Nitrogen is a constituent of every major pharmacological drug class, including antibiotics. Many notable nitrogen-containing drugs, such as the caffeine and morphine or the synthetic amphetamines. Nitrogen compounds have a long history, ammonium chloride having been known to Herodotus. They were well known by the Middle Ages, alchemists knew nitric acid as aqua fortis, as well as other nitrogen compounds such as ammonium salts and nitrate salts. The mixture of nitric and hydrochloric acids was known as aqua regia, celebrated for its ability to dissolve gold, the discovery of nitrogen is attributed to the Scottish physician Daniel Rutherford in 1772, who called it noxious air. Though he did not recognise it as a different chemical substance, he clearly distinguished it from Joseph Blacks fixed air. The fact that there was a component of air that does not support combustion was clear to Rutherford, Nitrogen was also studied at about the same time by Carl Wilhelm Scheele, Henry Cavendish, and Joseph Priestley, who referred to it as burnt air or phlogisticated air. Nitrogen gas was inert enough that Antoine Lavoisier referred to it as air or azote, from the Greek word άζωτικός. In an atmosphere of nitrogen, animals died and flames were extinguished
24.
Drag-reducing aerospike
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A drag-reducing aerospike is a device used to reduce the forebody pressure aerodynamic drag of blunt bodies at supersonic speeds. The aerospike creates a detached shock ahead of the body, between the shock and the forebody a zone of recirculating flow occurs which acts like a more streamlined forebody profile, reducing the drag. This concept was used on the UGM-96 Trident I and is estimated to have increased the range by 550 km, the use of the aerospike allowed a much blunter nose shape, providing increased internal volume for payload and propulsion without increasing the drag. This was required because the Trident I C-4 was fitted with a third stage to achieve the desired increase in range over the Poseidon C-3 missile it replaced. To fit within the submarine launch tubes the third-stage motor had to be mounted in the center of the post-boost vehicle with the reentry vehicles arranged around the motor. At the same time aerospike was developed in KBM for 9M39 surface-to-air missile of 9K38 Igla MANPADS, simplified Igla-1 version with a different kind of target seeker featured a tripod instead of needle for the same purpose. Further development of concept has resulted in the air-spike. This is formed by concentrated energy, either from an electric arc torch or a laser, projected forwards from the body. This has the advantage over a structural aerospike that the air density is lower than that behind a shock wave providing increased drag reduction, the UGM-133 Trident II missile is also fitted with a drag-reducing aerospike. AIAA 95-0737 - Experimental Results on the Feasibility of an Aerospike for Hypersonic Missiles, american Institute of Aeronautics and Astronautics
25.
Sub-orbital spaceflight
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For example, the path of an object launched from Earth that reaches 100 km above sea level, and then falls back to Earth, is considered a sub-orbital spaceflight. Some sub-orbital flights have been undertaken to test spacecraft and launch vehicles later intended for orbital spaceflight, other vehicles are specifically designed only for sub-orbital flight, examples include manned vehicles such as the X-15 and SpaceShipOne, and unmanned ones such as ICBMs and sounding rockets. Flights which attain sufficient velocity to go into low Earth orbit, examples of this include Yuri Gagarins Vostok 1, and flights of the Fractional Orbital Bombardment System. Usually a rocket is used, but experimental sub-orbital spaceflight has also achieved with a space gun. By one definition a sub-orbital spaceflight reaches a higher than 100 km above sea level. The US military and NASA award astronaut wings to those flying above 50 mi, during freefall the trajectory is part of an elliptic orbit as given by the orbit equation. The perigee distance is less than the radius of the Earth R including atmosphere, hence the ellipse intersects the Earth, the major axis is vertical, the semi-major axis a is more than R/2. The specific orbital energy ϵ is given by, ε = − μ2 a > − μ R where μ is the standard gravitational parameter, to minimize the required delta-v, the high-altitude part of the flight is made with the rockets off. The maximum speed in a flight is attained at the lowest altitude of this free-fall trajectory, if ones goal is simply to reach space, for example in competing for the Ansari X Prize, horizontal motion is not needed. In this case the lowest required delta-v, to reach 100 km altitude, is about 1.4 km/s, for sub-orbital spaceflights covering a horizontal distance the maximum speed and required delta-v are in between those of a vertical flight and a LEO. The maximum speed at the ends of the trajectory are now composed of a horizontal. The higher the horizontal distance covered, the greater both speeds will be, for the V-2 rocket, just reaching space but with a range of about 330 km, the maximum speed was 1.6 km/s. Scaled Composites SpaceShipTwo which is under development will have a similar free-fall orbit, for larger ranges, due to the elliptic orbit the maximum altitude can even be considerably more than for a LEO. It should be noted that any spaceflight that returns to the surface, including sub-orbital ones, the speed at the start of the reentry is basically the maximum speed of the flight. The aerodynamic heating caused will vary accordingly, it is less for a flight with a maximum speed of only 1 km/s than for one with a maximum speed of 7 or 8 km/s. Let θ be half the angle that the projectile is to go around the earth, the minimum-delta-v trajectory corresponds to an ellipse with one focus at the centre of the earth and the other at the point halfway between the launch point and the destination point. Longer ranges will have lower apogees in the minimal-delta-v solution and we see that the Δv increases with range, leveling off at 7.9 km/s as the range approaches 20000 km. The minimum-delta-v trajectory for going halfway around the world corresponds to a circular orbit just above the surface, see lower for the time of flight
26.
Charles Stark Draper Laboratory
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Draper is an American not-for-profit research and development organization, headquartered in Cambridge, Massachusetts, its official name is The Charles Stark Draper Laboratory, Inc. The laboratory specializes in the design, development, and deployment of advanced solutions to problems in national security, space exploration, health care. It was renamed for its founder in 1970 and separated from MIT in 1973 to become an independent, in 1932 Charles Stark Draper, an MIT aeronautics professor, created a teaching laboratory to develop the instrumentation needed for tracking, controlling and navigating aircraft. During World War II, Draper’s lab was known as the “Confidential Instrument Development Laboratory”, later, the name was changed to the MIT Instrumentation Laboratory. The laboratory was renamed for its founder in 1970 and remained a part of MIT until 1973 when it became an independent, not-for-profit research and development corporation. Draper has locations in several U. S. cities, Cambridge, MA Houston, TX at NASA Johnson Space Center Washington, DC Huntsville, AL Tampa, when appropriate, Draper works with partners to transition their technology to commercial production. Space Systems—As NASA’s technology development partner and transition agent for planetary exploration, development of GN&C, expertise also addresses the national security space sector. Special Programs—Concept development, prototyping, low-rate production, and field support for first-of-a-kind systems, biomedical Systems—Microelectromechanical systems, microfluidic applications of medical technology, and miniaturized smart medical devices. Air Warfare and ISR—Intelligence technology for targeting and target planning applications, project areas that have surfaced in the news referred to Draper Laboratorys core expertise in inertial navigation, as recently as 2003. The laboratory staff has studied ways to input from Global Positioning Systems into Inertial navigation system-based navigation in order to lower costs. Military inertial navigation systems cannot totally rely on GPS satellite availability for course correction—required by error growth—owing to blocking or jamming of signal, a less accurate inertial system usually means a less costly system, but one that requires more frequent checking of position from another source, like GPS. Systems that integrate GPS with INS are classified as “loosely coupled”, “tightly coupled”, or deeply integrated, to qualify for the prize, the robot must travel 500 meters across the lunar surface and transmit video, images and other data back to Earth. The algorithm takes into account everything that affects how the moves, including the position of its thrusters. Each CMG module is about the size of a deck of cards, the concept is for the garment to be worn in the lead-up to landing back on Earth or periodically throughout a long mission. The CMG-augmented suit would provide better counterforce than is now available for when astronauts use tools in low-gravity environments, counterforce is available on earth from gravity. Without it a force would result in an equal force in the opposite direction. In space this could send an astronaut out of control, currently, astronauts must affix themselves to the surface being worked on. The CMGs would offer an alternative to mechanical connection or gravitational force and this capability would allow an autonomous under fire to learn that that road is dangerous and find a safer route or to recognize that its fuel status and damage status
27.
Inertial navigation system
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It is used on vehicles such as ships, aircraft, submarines, guided missiles, and spacecraft. Other terms used to refer to inertial navigation systems or closely related devices include inertial guidance system, inertial instrument, inertial measurement units, older INS systems generally used an inertial platform as their mounting point to the vehicle, and the terms are sometimes considered synonymous. Inertial measurement units typically contain three orthogonal rate-gyroscopes and three accelerometers, measuring angular velocity and linear acceleration respectively. By processing signals from these devices it is possible to track the position and orientation of a device, Inertial navigation is used in a wide range of applications including the navigation of aircraft, tactical and strategic missiles, spacecraft, submarines and ships. Recent advances in the construction of systems have made it possible to manufacture small. These advances have widened the range of applications to include areas such as human. An inertial navigation system includes at least a computer and a platform or module containing accelerometers, gyroscopes, the advantage of an INS is that it requires no external references in order to determine its position, orientation, or velocity once it has been initialized. An INS can detect a change in its position, a change in its velocity. It does this by measuring the acceleration and angular velocity applied to the system. Since it requires no external reference, it is immune to jamming, Inertial navigation systems are used in many different moving objects, including vehicles—such as aircraft, submarines, spacecraft—and guided missiles. However, their cost and complexity place constraints on the environments in which they are practical for use, Gyroscopes measure the angular velocity of the sensor frame with respect to the inertial reference frame. By using the orientation of the system in the inertial reference frame as the initial condition and integrating the angular velocity. This can be thought of as the ability of a passenger in a car to feel the car turn left and right or tilt up. Based on this alone, the passenger knows what direction the car is facing but not how fast or slow it is moving. Accelerometers measure the acceleration of the moving vehicle in the sensor or body frame. Performing integration on the inertial accelerations using the correct kinematic equations yields the inertial velocities of the system, therefore, the position must be periodically corrected by input from some other type of navigation system. The inaccuracy of a good-quality navigational system is less than 0.6 nautical miles per hour in position and on the order of tenths of a degree per hour in orientation. Accordingly, inertial navigation is used to supplement other navigation systems
28.
Star tracker
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A star tracker is an optical device that measures the position of star using photocell or a camera. A star tracker may include a processor to identify stars by comparing the pattern of observed stars with the pattern of stars in the sky. Star trackers, which require high sensitivity, may become confused by sunlight reflected from the spacecraft, star trackers are also susceptible to a variety of errors in addition to a variety of optical sources of error. There are also many sources of confusion for the star identification algorithm. There are roughly 57 bright navigational stars in common use, however, for more complex missions, entire star field databases are used to determine spacecraft orientation. These types of star catalogs can have thousands of stored in memory on board the spacecraft, or else processed using tools at the ground station
29.
Missile guidance
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Missile guidance refers to a variety of methods of guiding a missile or a guided bomb to its intended target. The missiles target accuracy is a factor for its effectiveness. Guidance systems improve missile accuracy by improving its Single Shot Kill Probability and these guidance technologies can generally be divided up into a number of categories, with the broadest categories being active, passive and preset guidance. The concept of missile guidance originated at least as early as World War I, in World War II, guided missiles were first developed, as part of the German V-weapons program. Project Pigeon was American behaviorist B. F. Skinners attempt to develop a pigeon-guided missile, Guidance systems are divided into different categories according to what type of target they are designed for - either fixed targets or moving targets. The weapons can be divided into two categories, Go-Onto-Target and Go-Onto-Location-in-Space guidance systems. A GOT missile can target either a moving or fixed target, the trajectory that a missile takes while attacking a moving target is dependent upon the movement of the target. Also, a target can be an immediate threat to the sender of the missile. The target needs to be eliminated in a fashion in order to preserve the integrity of the sender. In GOLIS systems the problem is simpler because the target is not moving, the target tracker is also placed on the launching platform. Homing Guidance, The guidance computers are in the missile and in the target tracker and these systems include, Command guidance - The missile tracker is on the launching platform. These missiles are controlled by the launching platform that sends all control orders to the missile. The 2 variants are Command to Line-Of-Sight Command Off Line-Of-Sight Line-Of-Sight Beam Riding Guidance - The target tracker is on board the missile, the missile already has some orientation capability meant for flying inside the beam that the launching platform is using to illuminate the target. It can be manual or automatic, the CLOS system uses only the angular coordinates between the missile and the target to ensure the collision. The missile is made to be in the line of sight between the launcher and the target, and any deviation of the missile from this line is corrected. That is, the missile is controlled to stay as close as possible on the LOS to the target after missile capture. is used to transmit signals from a ground controller to the missile. More specifically, if the acceleration is taken into account and added to the nominal acceleration generated by the beam-rider equations. Thus, the beam rider acceleration command is modified to include an extra term, the beam-riding performance described above can thus be significantly improved by taking the beam motion into account
30.
UGM-27 Polaris
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The UGM-27 Polaris missile was a two-stage solid-fueled nuclear-armed submarine-launched ballistic missile built during the Cold War by Lockheed Corporation for the United States Navy. It was designed to be used for second strike countervalue as part of the Navys contribution to the United States arsenal of nuclear weapons, replacing the Regulus cruise missile. Known as a Fleet Ballistic Missile, the Polaris was first launched from the Cape Canaveral, Florida, following the Polaris Sales Agreement in 1963, Polaris missiles were also carried on British Royal Navy submarines between 1968 and the mid-1990s. Plans to equip the Italian Navy with the missile ended in the mid-60s, despite the successful launching tests, the plan was abandoned due to the completion of initial SSBN vessels. The Polaris missile was replaced on 31 of the 41 original SSBNs in the US Navy by the MIRV-capable Poseidon missile beginning in 1972. During the 1980s, these missiles were replaced on twelve of these submarines by the Trident I missile, the ten George Washington- and Ethan Allen-class SSBNs retained Polaris A-3 until 1980 because their missile tubes were not large enough to accommodate Poseidon. With USS Ohio commencing sea trials in 1980, these submarines were disarmed and redesignated as attack submarines to avoid exceeding the SALT II strategic arms treaty limits. Many new project management techniques were introduced during the development of the Polaris missile program and this includes the use of the Program Evaluation and Review Technique. This technique replaced the simpler Gantt chart methodology which was largely employed prior to this program, the Polaris missile replaced an earlier plan to create a submarine-based missile force based on a derivative of the U. S. Army Jupiter Intermediate-range ballistic missile. Chief of Naval Operations Admiral Arleigh Burke appointed Rear Admiral W. F, red Raborn as head of a Special Project Office to develop Jupiter for the Navy in late 1955. The Jupiter missiles large diameter was a product of the need to keep the length short enough to fit in a reasonably-sized submarine, Polaris was spearheaded by the Special Project Offices Missile Branch under Rear Admiral Roderick Osgood Middleton, and is still under the Special Project Office. Admiral Burke later was instrumental in determining the size of the Polaris submarine force, eventually, the number of Polaris submarines was fixed at 41. There is a contention that the Navys Jupiter missile program was unrelated to the Army program, a huge surfaced submarine would carry four Jupiter missiles, which would be carried and launched horizontally. This was probably the never-built SSM-N-2 Triton program, however, a history of the Armys Jupiter program states that the Navy was involved in the Army program, but withdrew at an early stage. Submarines were very vulnerable to attack during launch, and a fully or partially fueled missile on deck was a serious hazard, rough weather was another major drawback for these designs, but rough sea conditions did not unduly affect Polaris submerged launches. The prime contractor for all three versions of Polaris was Lockheed Missiles and Space Company, now Lockheed Martin, the Polaris program started development in 1956. USS George Washington, the first US missile submarine, successfully launched the first Polaris missile from a submarine on July 20,1960. The A-2 version of the Polaris missile was essentially an upgraded A-1 and it was fitted on a total of 13 submarines and served until June 1974
31.
UGM-73 Poseidon
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The UGM-73 Poseidon missile was the second US Navy nuclear-armed submarine-launched ballistic missile system, powered by a two-stage solid-fuel rocket. It succeeded the UGM-27 Polaris beginning in 1972, bringing major advances in warheads and it was followed by Trident I in 1979, and Trident II in 1990. A development study for a longer version of the Polaris missile achieved by enlarging it to the maximum possible size allowed by existing launch tubes started in 1963. Tests had already shown that Polaris missiles could be operated without problems in launch tubes that had their fiberglass liners, the project was given the title Polaris B3 in November, but the missile was eventually named Poseidon C3 to emphasize the technical advances over its predecessor. The C3 was the version of the missile produced. MIRV capacity has been given as up to ten or fourteen W68 thermonuclear warheads contained in Mark 3 reentry vehicles to multiple targets. As with Polaris, starting a motor when the missile was still in the submarine was considered very dangerous. Therefore, the missile was ejected from its launch tube using high pressure produced by a solid-fueled boiler. The main rocket motor ignited automatically when the missile had risen approximately 10 metres above the submarine, the weapon officially entered service on 31 March 1971. It eventually equipped 31 Lafayette-, James Madison-, and Benjamin Franklin-class submarines, the Royal Navy also considered adopting Poseidon in the 1970s as an upgrade to its Polaris A3T boats, and like the US this would have kept the existing hulls. Beginning in 1979,12 Poseidon-equipped SSBNs were refitted with Trident I, United States United States Navy List of missiles
32.
James Madison-class submarine
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The James Madison class of submarine was an evolutionary development from the Lafayette class of fleet ballistic missile submarine. They were identical to the Lafayettes except for being designed to carry the Polaris A-3 missile instead of the earlier A-2. This class and the Benjamin Franklin class are combined with the Lafayettes in some references, in the early 1970s all were modified for the Poseidon C-3 missile. During the late 1970s and early 1980s, six boats were modified to carry the Trident I C-4 missile. These were James Madison, Daniel Boone, John C, calhoun, Von Steuben, Casimir Pulaski, and Stonewall Jackson. The James Madisons were decommissioned between 1986 and 1995 due to a combination of SALT II treaty limitations as the Ohio class SSBNs entered service, age, one remains out of commission but converted to a Moored Training Ship with the missile compartment removed. She is stationed at Nuclear Power Training Unit Charleston, South Carolina, conways All The Worlds Fighting Ships 1947-1995. Annapolis, USA, Naval Institute Press,1995, the Ships and Aircraft of the U. S. Fleet, Twelfth Edition. US Naval Vessel Register - List of SSBN BALLISTIC MISSILE SUBMARINE Class vessels This article incorporates text from the public domain Dictionary of American Naval Fighting Ships
33.
UGM-133 Trident II
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The UGM-133A Trident II, or Trident D5 is a submarine-launched ballistic missile, built by Lockheed Martin Space Systems in Sunnyvale, California, and deployed with the American and British navies. It was first deployed in March 1990, and remains in service, the Trident II Strategic Weapons System is an improved SLBM with greater accuracy, payload, and range than the earlier Trident C-4. It is a key element of the U. S. strategic nuclear triad, the Trident II is considered to be a durable sea-based system capable of engaging many targets. It enhances the U. S. position in strategic arms negotiation with performance, Trident II missiles are carried by 14 US Ohio and 4 British Vanguard-class submarines, with 24 missiles on each Ohio class and 16 missiles on each Vanguard class. There have been 161 successful test flights of the D5 missile since design completion in 1989, there have been fewer than 10 test flights that were failures, the most recent being from HMS Vengeance off the coast of Florida in June 2016. The D5 is the sixth in a series of missile generations deployed since the sea-based deterrent program began 60 years ago, the Trident D5LE version will remain in service until 2042. Lockheed Martin designs and manufactures the Trident II Missile as well as all generations of US Fleet Ballistic Missiles. The Trident II was designated to be the latest longer-range missile, in 1972, the US Navy projected an initial operating capability date for the Trident II in 1984. The US Navy continued to advance the IOC date to 1982, on 18 October 1973, a Trident program review was administered. On 14 March 1974, the US Deputy Secretary of Defense disseminated two requirements for the Trident program, the first was an accuracy improvement for the Trident C-4. The second requirement asked for an alternative to the C-4, or a new Trident II missile with a larger first stage motor than the C-4, studies were conducted to determine whether the more-expensive Trident II could be constructed similar to the US Air Forces MX ICBM. This was done primarily to decrease budget costs and it was established that the Trident II would be 83 inches in diameter and 44 ft in length in order to maintain performance with the existing MX ICBM. Modifications to the system, electronics hardening, and external protective coatings were incorporated into the design. While this satisfied the US Naval study requirements, it did not accommodate the US Air Force payload requirements, propulsion stages were proposed to be used between the first stage and second stage motors, effectively making the Trident II a longer three-stage missile than the C-4. Studies were delayed in 1978 when Congress only approved $5 million of the suggested $15 million for the Naval/Air Force program studies, by December 1978, the US Navy and Air Force studies agreed that the savings made by a similar missile structure would not be effective. It was determined that the US Navy and Air Force maintain, the US Navy continued with their own weapon design of the Trident II. In March 1980, US Secretary of Defense Harold Brown proposed an increased level of funding for the ballistic missile modernization. Emphasis was strained for the need of increased accuracy, the House Armed Services Committee recommended no funding, while the Senate Armed Services Committee recommended full funding of $97 million
34.
First strike
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In nuclear strategy, a first strike is a preemptive surprise attack employing overwhelming force. The preferred methodology is to attack the strategic nuclear weapon facilities, command and control sites. During the Cold War period, both superpowers, NATO and the Eastern Bloc, built massive nuclear arsenals, aimed, to a large extent, therefore, at times, both sides refrained from deploying systems capable of unanswerable nuclear strikes against either side. In addition, each side doubted the other sides commitment to not deploy first-strike weapons, or even in the event of their deployment, some first-strike weapons were deployed, however like most nuclear weapons, they were never used. Of the nuclear powers, only the Peoples Republic of China and India have declarative, unqualified, unconditional no-first-use policies. In 1982, at a session of the General Assembly of United Nations. This pledge was abandoned by post-Soviet Russia to compensate the overwhelming conventional weapon superiority enjoyed by NATO. The United States has a partial, qualified no-first-use policy, stating that they not use nuclear weapons against states that do not possess nuclear weapons or other weapons of mass destruction. Large-scale missile defense systems are not first-strike weapons, but certain critics view them as first-strike enabling weapons and these proposed defense systems, intended to lessen the risk of devastating nuclear war, would lead to it, according to these critics. Indeed, according to theory, the side not building large-scale missile defenses would have an incentive to launch a pre-emptive first strike while such a strike could still get through. First-strike attack, the use of a nuclear first strike capability, was feared during the Cold War between NATO and the Soviet Bloc. At various points, fear of a first strike attack existed on both sides, misunderstood changes in posture and well understood changes in technology used by either side often led to speculation regarding the enemys intentions. The USSR countered by developing their own nuclear weapons, surprising the US with their first test in 1949. The 1960 U-2 incident, involving Francis Gary Powers, as well as the Berlin Crisis, along with the test of the Tsar Bomba and this escalating situation came to a head with the Cuban Missile Crisis of 1962. However harsh and terrible the solution, there would be no other, the Cuban Missile Crisis resulted in Khrushchev publicly agreeing to remove the missiles from Cuba, while Kennedy secretly agreed to remove his countrys missiles from Turkey. Both sides in the Cold War realized how close they came to war over Cuba. Nonetheless, this reduction of tensions only applied to the US, the Soviet Union, in response, sent experts to spell out for Castro the ecological consequences for Cuba of nuclear strikes on the United States. Castro, according to the General, quickly became convinced of the undesirability of such outcomes. S, president Ronald Reagans talk of limited nuclear war
35.
Counterforce
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The intent of a counterforce strategy is to disarm an adversary by destroying its nuclear weapons before they can be launched, thereby minimizing the impact of a retaliatory second strike. However, counterforce attacks are possible in a second strike. A counterforce target is distinguished from a target, which includes an adversarys population, knowledge, economic. In other words, a strike is against an adversarys military while a countervalue strike is against an adversarys cities. In nuclear warfare, enemy targets are divided into two types, counterforce and countervalue, a counterforce target is an element of the military infrastructure, usually either specific weapons or the bases which support them. A counterforce strike is an attack which targets these elements whilst leaving the civilian infrastructure – the countervalue targets – as undamaged as possible, countervalue refers to the targeting of an opponents cities and civilian populations. An ideal counterforce attack would kill no civilians, military attacks are prone to causing collateral damage however, and this is especially true when nuclear weapons are employed. Counterforce weapons could be seen to provide more credible deterrence in future conflict by providing options for leaders, one of those options considered by the Soviet Union in the 1970s is basing missiles in orbit. Counterforce is a type of attack which was proposed during the Cold War. Later generation missiles with much improved accuracy made counterforce attacks against the opponents hardened military facilities possible, both sides in the Cold War took steps to protect at least some of their nuclear forces from counter-force attacks. At one point the US kept B-52 Stratofortress bombers permanently in flight, other bombers were kept ready for launch on short notice, allowing them to escape their bases before intercontinental ballistic missiles could destroy them. Submarines themselves, however, are immune from counter-force strikes. A counter-force exchange was one scenario mooted for a limited nuclear war. Critics of this idea claimed that even a counter-force strike would kill millions of civilians it is unlikely that escalation to a full-scale counter-value war could be prevented. MIRVed land-based ICBMs are considered destabilizing because they tend to put a premium on striking first. In this case, the side that strikes first can reduce the enemy ICBM force from 100 missiles to about 5 by firing 40 missiles with 200 warheads, and keeping the rest of 60 missiles in reserve. For such an attack to be successful, the warheads would have to strike their targets prior to the launching a counter-attack. It is because of this that this type of weapon was banned under the START II agreement, deployed in 1976, this counterforce MIRV ICBM had single or 10 MIRV warheads, CEP250 m
36.
Second strike
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In nuclear strategy, a second-strike capability is a countrys assured ability to respond to a nuclear attack with powerful nuclear retaliation against the attacker. The possession of second-strike capabilities counters a first-strike nuclear threat and can support a no first use nuclear strategy, reciprocal second-strike capabilities usually cause a mutual assured destruction defence strategy, though one side may have a lower level minimal deterrence response. Second-strike capabilities can be strengthened by implementing fail-deadly mechanisms. These mechanisms create a threshold and guaranteed consequences if that threshold is breached, for instance, a threshold may be for an allied nation not to be attacked. If a rival nation then breaches this threshold by attacking the allied nation and these predetermined consequences could include a wide range of responses, including a retaliatory nuclear second strike. The crucial goal in maintaining second-strike capabilities is preventing first-strike attacks from taking out a nuclear arsenal. In this manner, a country can carry out nuclear retaliation even after absorbing a nuclear attack, the United States and other countries have diversified their nuclear arsenals through the nuclear triad in order to better ensure second-strike capability. Using SLBMs as a second-strike capability has a problem, because in retaliation for a submarine-launched ICBM, the wrong country could be targeted. However, implementation of second strikes is crucial to deter a first strike, countries with nuclear weapons make it their primary purpose to convince their opponents that a first strike is not worth facing a second strike. Launch on warning is a strategy of nuclear retaliation that gained recognition during the Cold War between the Western Bloc and the Eastern Bloc. In addition to the triad, nations deploy an early warning system that detects incoming nuclear missiles. This gives that nation the capability and option to launch a second strike before the incoming nuclear first strike hits any of its targets. This is another method of solidifying second-strike capabilities and deterring a first strike from another nuclear power, because of the low accuracy of early-generation intercontinental ballistic missiles, second strike was initially only possible against very large, undefended countervalue targets like cities. Later-generation missiles with much improved accuracy made counterforce attacks against the opponents hardened military facilities possible. Perimetr PTS dates back to 1974, in response to Soviet fears of devastating nuclear strikes from US Ballistic Missile submarines and it became operational in January 1985, with SS-17 launch silos in Vypolzovo and Kostroma, each 100 and 150 miles north-west of Moscow respectively. The system was built with layers of redundancy, in case multiple layers of communications were destroyed in the initial strike. Launch authorisation would be transmitted by UHF radio, by transmitters buried deep underground, development continued over the years with the system incorporating the new SS-27 ICBMs in December 1990, and further refinements in 1996. Russian leadership was concerned that the system could trigger an accidental launch, initially, both the Vyuga nuclear command link to Russian leadership and the secure Kazbek communications system must be interrupted
37.
Carbon fiber reinforced polymer
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Carbon fiber reinforced polymer, carbon fiber reinforced plastic or carbon fiber reinforced thermoplastic, is an extremely strong and light fiber-reinforced plastic which contains carbon fibers. The spelling fibre is common in British Commonwealth countries, the binding polymer is often a thermoset resin such as epoxy, but other thermoset or thermoplastic polymers, such as polyester, vinyl ester or nylon, are sometimes used. The composite may contain other fibers, such as an aramid, aluminium, ultra-high-molecular-weight polyethylene or glass fibers, the properties of the final CFRP product can also be affected by the type of additives introduced to the binding matrix. The most frequent additive is silica, but other such as rubber. The material is referred to as graphite-reinforced polymer or graphite fiber-reinforced polymer. In product advertisements, it is referred to simply as graphite fiber for short. In this case the composite consists of two parts, a matrix and a reinforcement, in CFRP the reinforcement is carbon fiber, which provides the strength. The matrix is usually a resin, such as epoxy. Because CFRP consists of two elements, the material properties depend on these two elements. The reinforcement will give the CFRP its strength and rigidity, measured by stress, unlike isotropic materials like steel and aluminum, CFRP has directional strength properties. The properties of CFRP depend on the layouts of the carbon fiber, the following equation, E c = V m E m + V f E f is valid for composite materials with the fibers oriented in the direction of the applied load. Typical epoxy-based CFRPs exhibit virtually no plasticity, with less than 0. 5% strain to failure, although CFRPs with epoxy have high strength and elastic modulus, the brittle fracture mechanics present unique challenges to engineers in failure detection since failure occurs catastrophically. As such, recent efforts to toughen CFRPs include modifying the existing epoxy material, One such material with high promise is PEEK, which exhibits an order of magnitude greater toughness with similar elastic modulus and tensile strength. However, PEEK is much more difficult to process and more expensive, despite its high initial strength-to-weight ratio, a design limitation of CFRP is its lack of a definable fatigue endurance limit. This means, theoretically, that stress cycle failure cannot be ruled out, environmental effects such as temperature and humidity can have profound effects on the polymer-based composites, including most CFRPs. While the carbon fibers themselves are not affected by the moisture diffusing into the material, the carbon fibers can cause galvanic corrosion when CRP parts are attached to aluminum. The primary element of CFRP is a filament, this is produced from a precursor polymer such as polyacrylonitrile, rayon. Precursor compositions and mechanical processes used during spinning filament yarns may vary among manufacturers, after drawing or spinning, the polymer filament yarns are then heated to drive off non-carbon atoms, producing the final carbon fiber
38.
USS Maryland (SSBN-738)
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USS Maryland is a United States Navy Ohio-class ballistic missile submarine. Maryland is the 13th of 18 of the Ohio-class ballistic missile submarines, Maryland is the fourth United States Navy vessel to be named after the U. S. state of Maryland. Her mission is to provide the United States of America with an undetectable and unattackable nuclear launch platform in support of the strategy of strategic deterrence. The contract for the construction of the Maryland was awarded on 14 March 1986 and her keel was laid down by the Electric Boat Division of the General Dynamics Corporation at Groton, Connecticut, on 22 April 1986. Maryland was christened and launched in a ceremony on 10 August 1991 at the Electric Boat shipyard. The program opened with the U. S. national anthem, The Star-Spangled Banner, performed by the United States Navy Band, Northeast, mr. Roger E. Tetrault, Vice President and General Manager of Electric Boat Division, then gave welcoming remarks. Executive Vice President of Marine, Land Systems and Services, General Dynamics Corporation, the director of the Maryland Veterans Commission, Clarence M. Bacon, greeted guests and crew, then turned over the podium to Vice Admiral Kenneth C. Malley, Commander, Naval Sea Systems Command, Vice Admiral Henry G. Chiles, Jr. Commander Submarine Force U. S. Atlantic Fleet, introduced the speaker, The Honorable Helen Delich Bentley U. S. Representative for Marylands Second Congressional District, mr. James E. Turner Jr. then returned to the podium to introduce the sponsor, Sarah Sally Craig Larson. The principal speaker was Admiral Charles R. Larson, Commander-in-Chief U. S, at this point the Blue crew retained the ship for shakedown operations, while the Gold crew departed to Naval Submarine Base Kings Bay, Kings Bay, Georgia to start their offcrew training cycle. The first exchange of command occurred on 4 September 1992, with the Gold crew taking charge of Maryland, various other inspections and training exercises were conducted throughout 1992. The Blue crew relieved the Gold crew 26 January 1993 and continued preparations for strategic certification. Maryland returned to Groton on 30 January 1993 for post-shakedown maintenance prior to assuming responsibility for strategic deterrent patrols, Maryland returned to Kings Bay, Georgia on 9 April 1993. The initial loadout of Trident D-5 missiles was completed at this point, the Gold crew relieved the Blue crew 7 May 1993 and continued the refit. On 19 June 1993 Maryland went underway on her first strategic deterrent patrol, on 24 September 1993, Maryland ran aground at Port Canaveral, Florida, after conducting a medical evacuation of an ill crew member, and returned to Kings Bay to inspect for damage. Damage to the submarine was minimal, and the found that the crew was not responsible. Maryland then resumed her second deterrent patrol on 26 September 1993, on 5 May 2002, ETC LeRoy W. Young, USN, died of a heart attack while deployed on Maryland
39.
HMS Vengeance (S31)
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HMS Vengeance is the fourth and final Vanguard-class submarine of the Royal Navy. Vengeance carries the Trident ballistic missile, the UKs nuclear deterrent, Vengeance was built at Barrow-in-Furness by Vickers Shipbuilding and Engineering Ltd, was launched in September 1998, and commissioned in November 1999. Before she was commissioned, the British Government stated that once the Vanguard submarines became fully operational, Vengeance carries the unopened last instructions of the current British Prime Minister that are to be used in the event of a national catastrophe or a nuclear strike. On 31 March 2011, while on a training exercise Vengeance suffered a blockage in her propulsor causing a reduction in propulsion, the boat returned to Faslane naval base on the surface under her own power. According to the MOD the problems were not nuclear related, in 2012, Vengeance started a 40 month refit at HMNB Devonport near Plymouth which refueled her reactor and re-newed her machinery and electronics. During that period her sister ship Vigilant took her place in the patrol rotations and she sailed from Devonport on 4 December 2015, her place in refit being taken by Vanguard. Vengeance then went through trials from January 2016 to June 2016 and fired an unarmed D5 missile during her Demonstration, whilst the firing of the missile was a success, the missile itself suffered a failure during flight and the test was terminated
40.
Naval Submarine Base Kings Bay
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The Submarine Base is the U. S. Atlantic Fleets home port for U. S. Navy Fleet ballistic missile submarines armed with Trident missile nuclear weapons. This submarine base covers about 16,000 acres of land, archeological research has revealed a pre-Columbian Indian presence throughout the area, dating back thousands of years. Early in the 19th century, much of what is now the base was the site of several plantations, including Cherry Point, Harmony Hall, New Canaan, Marianna. Beginning in the 1790s, Thomas King built a plantation along the bay, john Houston McIntosh built a considerably larger plantation known as New Canaan, where he grew cotton and sugar cane. The plantation system declined following the Civil War, and the land was broken up into smaller holdings, no residents were paid the going rate for the land that was used to build the submarine base. One land owner was paid four dollars for 62 acres of deep water land. Such residents harvested shrimp, fish and other seafood, and trapped and hunted to supplement small-scale farming of corn, sugar and other vegetables. The US Army began to acquire 7,000 acres of land at Kings Bay in 1954 to build a military ocean terminal to ship ammunition in case of a national emergency, construction began in 1955 and was completed in 1958. A200 wide channel was dredged to Cumberland Sound, and included two turning basins, the most prominent feature of the terminal was its 2, 000-foot -long, 87-foot -wide concrete and steel wharf. It had three railroad tracks, enabling the simultaneous loading of several ammunition ships from rail cars. Elsewhere on the base, the Army laid 47 miles of railroad tracks, spurs off the main line ran into temporary storage areas protected by earthen barricades. These mounds of dirt, still prominent features in many areas of the base, were designed to damage in case of explosive accidents. Although the Army Post was never activated to serve its primary purpose, in 1964, as Hurricane Dora hammered the area, nearly 100 area residents were sheltered aboard base. Also, during the Cuban Missile Crisis, an Army Transportation Battalion of 1,100 personnel and 70 small boats took up position at Kings Bay, at that time, treaty negotiations between Spain and the United States were in progress. Anticipating that this would take place, the Chief of Naval Operations ordered studies to select a new site on the East Coast. In January 1976, the negotiators initialed a draft treaty between Spain and the United States and it called for withdrawal of the submarine squadron from Rota by July 1979. The U. S. Senate ratified the treaty in June 1976, after careful review, Kings Bay was selected in November 1976, shortly after the election of the Georgian Jimmy Carter as the President
41.
The Pentagon
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The Pentagon is the headquarters of the United States Department of Defense, located in Arlington County, Virginia, across the Potomac River from Washington, D. C. As a symbol of the U. S. military, The Pentagon is often used metonymically to refer to the U. S. Department of Defense, the Pentagon was designed by American architect George Bergstrom, and built by general contractor John McShain of Philadelphia. Ground was broken for construction on September 11,1941, General Brehon Somervell provided the major motive power behind the project, Colonel Leslie Groves was responsible for overseeing the project for the U. S. Army. The Pentagon is one of the worlds largest office buildings, with about 6,500,000 sq ft, approximately 23,000 military and civilian employees and about 3,000 non-defense support personnel work in the Pentagon. It has five sides, five floors above ground, two basement levels, and five ring corridors per floor with a total of 17.5 mi of corridors. It was the first significant foreign attack on Washingtons governmental facilities since the city was burned by the British, when World War II broke out in Europe, the War Department rapidly expanded in anticipation that the United States would be drawn into the conflict. Secretary of War Henry L. Stimson found the situation unacceptable, with the Munitions Building overcrowded, Stimson told U. S. President Franklin D. Roosevelt in May 1941 that the War Department needed additional space. On July 17,1941, a hearing took place, organized by Virginia congressman Clifton Woodrum. Reybold agreed to back to the congressman within five days. The War Department called upon its construction chief, General Brehon Somervell, Government officials agreed that the War Department building, officially designated Federal Office Building No 1, should be constructed across the Potomac River, in Arlington County, Virginia. Requirements for the new building were that it be no more than four stories tall, the requirements meant that, instead of rising vertically, the building would be sprawling over a large area. Possible sites for the building included the Department of Agricultures Arlington Experimental Farm, adjacent to Arlington National Cemetery, the site originally chosen was Arlington Farms which had a roughly pentagonal shape, so the building was planned accordingly as an irregular pentagon. Concerned that the new building could obstruct the view of Washington, D. C. from Arlington Cemetery, the building retained its pentagonal layout because a major redesign at that stage would have been costly, and Roosevelt liked the design. Freed of the constraints of the asymmetric Arlington Farms site, it was modified into a pentagon which resembled the star forts of the gunpowder age. While the project went through the process in late July 1941, Somervell selected the contractors, including John McShain, Inc. and Doyle and Russell. In addition to the Hoover Airport site and other government-owned land, construction of the Pentagon required an additional 287 acres, which were acquired at a cost of $2.2 million. The Hells Bottom neighborhood, a slum with numerous pawnshops, factories, approximately 150 homes, Later 300 acres of land were transferred to Arlington National Cemetery and to Fort Myer, leaving 280 acres for the Pentagon. Contracts totaling $31,100,000 were finalized with McShain and the contractors on September 11
42.
Atmospheric entry
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Atmospheric entry is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet or natural satellite. Technologies and procedures allowing the atmospheric entry, descent and landing of spacecraft are collectively abbreviated as EDL. Atmospheric drag and aerodynamic heating can cause atmospheric breakup capable of completely disintegrating smaller objects and these forces may cause objects with lower compressive strength to explode. Manned space vehicles must be slowed to subsonic speeds before parachutes or air brakes may be deployed, such vehicles have kinetic energies typically between 50 and 1800 MJoules, and atmospheric dissipation is the only way of expending the kinetic energy. While the high temperature generated at the surface of the shield is due to adiabatic compression. Other smaller energy losses include black body radiation directly from the hot gasses, ballistic warheads and expendable vehicles do not require slowing at re-entry, and in fact, are made streamlined so as to maintain their speed. Uncontrolled, objects accelerate through the atmosphere at extreme velocities under the influence of Earths gravity, most controlled objects enter at hypersonic speeds due to their suborbital, orbital, or unbounded trajectories. Various advanced technologies have developed to enable atmospheric reentry and flight at extreme velocities. Practical development of systems began as the range and reentry velocity of ballistic missiles increased. For early short-range missiles, like the V-2, stabilization and aerodynamic stress were important issues, medium-range missiles like the Soviet R-5, with a 1200 km range, required ceramic composite heat shielding on separable reentry vehicles. The first ICBMs, with ranges of 8000 to 12,000 km, were possible with the development of modern ablative heat shields. In the U. S. this technology was pioneered by H. Julian Allen at Ames Research Center, over the decades since the 1950s, a rich technical jargon has grown around the engineering of vehicles designed to enter planetary atmospheres. It is recommended that the review the jargon glossary before continuing with this article on atmospheric reentry. When atmospheric entry is part of a landing or recovery, particularly on a planetary body other than Earth, entry is part of a phase referred to as entry, descent and landing. When the atmospheric entry returns to the body that the vehicle had launched from. These four shadowgraph images represent early reentry-vehicle concepts, if the reentry vehicle is made blunt, air cannot get out of the way quickly enough, and acts as an air cushion to push the shock wave and heated shock layer forward. Since most of the hot gases are no longer in contact with the vehicle. The Allen and Eggers discovery, though initially treated as a secret, was eventually published in 1958
43.
Global Positioning System
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The Global Positioning System is a space-based radionavigation system owned by the United States government and operated by the United States Air Force. The GPS system operates independently of any telephonic or internet reception, the GPS system provides critical positioning capabilities to military, civil, and commercial users around the world. The United States government created the system, maintains it, however, the US government can selectively deny access to the system, as happened to the Indian military in 1999 during the Kargil War. The U. S. Department of Defense developed the system and it became fully operational in 1995. Roger L. Easton of the Naval Research Laboratory, Ivan A, getting of The Aerospace Corporation, and Bradford Parkinson of the Applied Physics Laboratory are credited with inventing it. Announcements from Vice President Al Gore and the White House in 1998 initiated these changes, in 2000, the U. S. Congress authorized the modernization effort, GPS III. In addition to GPS, other systems are in use or under development, mainly because of a denial of access. The Russian Global Navigation Satellite System was developed contemporaneously with GPS, GLONASS can be added to GPS devices, making more satellites available and enabling positions to be fixed more quickly and accurately, to within two meters. There are also the European Union Galileo positioning system and Chinas BeiDou Navigation Satellite System, special and general relativity predict that the clocks on the GPS satellites would be seen by the Earths observers to run 38 microseconds faster per day than the clocks on the Earth. The GPS calculated positions would quickly drift into error, accumulating to 10 kilometers per day, the relativistic time effect of the GPS clocks running faster than the clocks on earth was corrected for in the design of GPS. The Soviet Union launched the first man-made satellite, Sputnik 1, two American physicists, William Guier and George Weiffenbach, at Johns Hopkinss Applied Physics Laboratory, decided to monitor Sputniks radio transmissions. Within hours they realized that, because of the Doppler effect, the Director of the APL gave them access to their UNIVAC to do the heavy calculations required. The next spring, Frank McClure, the deputy director of the APL, asked Guier and Weiffenbach to investigate the inverse problem — pinpointing the users location and this led them and APL to develop the TRANSIT system. In 1959, ARPA also played a role in TRANSIT, the first satellite navigation system, TRANSIT, used by the United States Navy, was first successfully tested in 1960. It used a constellation of five satellites and could provide a navigational fix approximately once per hour, in 1967, the U. S. Navy developed the Timation satellite, which proved the feasibility of placing accurate clocks in space, a technology required by GPS. In the 1970s, the ground-based OMEGA navigation system, based on comparison of signal transmission from pairs of stations. Limitations of these systems drove the need for a more universal navigation solution with greater accuracy, during the Cold War arms race, the nuclear threat to the existence of the United States was the one need that did justify this cost in the view of the United States Congress. This deterrent effect is why GPS was funded and it is also the reason for the ultra secrecy at that time
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Tungsten
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Tungsten, also known as wolfram, is a chemical element with symbol W and atomic number 74. The word tungsten comes from the Swedish language tung sten, which translates to heavy stone. Its name in Swedish is volfram, however, in order to distinguish it from scheelite, a hard, rare metal under standard conditions when uncombined, tungsten is found naturally on Earth almost exclusively in chemical compounds. It was identified as a new element in 1781, and first isolated as a metal in 1783 and its important ores include wolframite and scheelite. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all the elements discovered, melting at 3,422 °C,6,192 °F. Its high density is 19.3 times that of water, comparable to that of uranium and gold, polycrystalline tungsten is an intrinsically brittle and hard material, making it difficult to work. However, pure single-crystalline tungsten is more ductile, and can be cut with a hard-steel hacksaw, tungstens many alloys have numerous applications, including incandescent light bulb filaments, X-ray tubes, electrodes in TIG welding, superalloys, and radiation shielding. Tungstens hardness and high density give it military applications in penetrating projectiles, tungsten compounds are also often used as industrial catalysts. Tungsten is the metal from the third transition series that is known to occur in biomolecules. It is the heaviest element known to be essential to any living organism, tungsten interferes with molybdenum and copper metabolism and is somewhat toxic to animal life. In its raw form, tungsten is a hard metal that is often brittle. If made very pure, tungsten retains its hardness, and becomes malleable enough that it can be worked easily and it is worked by forging, drawing, or extruding. Tungsten objects are commonly formed by sintering. Of all metals in pure form, tungsten has the highest melting point, lowest vapor pressure, although carbon remains solid at higher temperatures than tungsten, carbon sublimes, rather than melts, so tungsten is considered to have a higher melting point. Tungsten has the lowest coefficient of expansion of any pure metal. The low thermal expansion and high melting point and tensile strength of tungsten originate from strong covalent bonds formed between tungsten atoms by the 5d electrons, alloying small quantities of tungsten with steel greatly increases its toughness. Tungsten exists in two crystalline forms, α and β. The former has a cubic structure and is the more stable form
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Metre
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The metre or meter, is the base unit of length in the International System of Units. The metre is defined as the length of the path travelled by light in a vacuum in 1/299792458 seconds, the metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole. In 1799, it was redefined in terms of a metre bar. In 1960, the metre was redefined in terms of a number of wavelengths of a certain emission line of krypton-86. In 1983, the current definition was adopted, the imperial inch is defined as 0.0254 metres. One metre is about 3 3⁄8 inches longer than a yard, Metre is the standard spelling of the metric unit for length in nearly all English-speaking nations except the United States and the Philippines, which use meter. Measuring devices are spelled -meter in all variants of English, the suffix -meter has the same Greek origin as the unit of length. This range of uses is found in Latin, French, English. Thus calls for measurement and moderation. In 1668 the English cleric and philosopher John Wilkins proposed in an essay a decimal-based unit of length, as a result of the French Revolution, the French Academy of Sciences charged a commission with determining a single scale for all measures. In 1668, Wilkins proposed using Christopher Wrens suggestion of defining the metre using a pendulum with a length which produced a half-period of one second, christiaan Huygens had observed that length to be 38 Rijnland inches or 39.26 English inches. This is the equivalent of what is now known to be 997 mm, no official action was taken regarding this suggestion. In the 18th century, there were two approaches to the definition of the unit of length. One favoured Wilkins approach, to define the metre in terms of the length of a pendulum which produced a half-period of one second. The other approach was to define the metre as one ten-millionth of the length of a quadrant along the Earths meridian, that is, the distance from the Equator to the North Pole. This means that the quadrant would have defined as exactly 10000000 metres at that time. To establish a universally accepted foundation for the definition of the metre, more measurements of this meridian were needed. This portion of the meridian, assumed to be the length as the Paris meridian, was to serve as the basis for the length of the half meridian connecting the North Pole with the Equator
