The Soviet Union the Union of Soviet Socialist Republics, was a socialist state in Eurasia that existed from 1922 to 1991. Nominally a union of multiple national Soviet republics, its government and economy were centralized; the country was a one-party state, governed by the Communist Party with Moscow as its capital in its largest republic, the Russian Soviet Federative Socialist Republic. Other major urban centres were Leningrad, Minsk, Alma-Ata, Novosibirsk, it spanned over 10,000 kilometres east to west across 11 time zones, over 7,200 kilometres north to south. It had five climate zones: tundra, steppes and mountains; the Soviet Union had its roots in the 1917 October Revolution, when the Bolsheviks, led by Vladimir Lenin, overthrew the Russian Provisional Government which had replaced Tsar Nicholas II during World War I. In 1922, the Soviet Union was formed by a treaty which legalized the unification of the Russian, Transcaucasian and Byelorussian republics that had occurred from 1918. Following Lenin's death in 1924 and a brief power struggle, Joseph Stalin came to power in the mid-1920s.
Stalin committed the state's ideology to Marxism–Leninism and constructed a command economy which led to a period of rapid industrialization and collectivization. During his rule, political paranoia fermented and the Great Purge removed Stalin's opponents within and outside of the party via arbitrary arrests and persecutions of many people, resulting in at least 600,000 deaths. In 1933, a major famine struck the country. Before the start of World War II in 1939, the Soviets signed the Molotov–Ribbentrop Pact, agreeing to non-aggression with Nazi Germany, after which the USSR invaded Poland on 17 September 1939. In June 1941, Germany broke the pact and invaded the Soviet Union, opening the largest and bloodiest theatre of war in history. Soviet war casualties accounted for the highest proportion of the conflict in the effort of acquiring the upper hand over Axis forces at intense battles such as Stalingrad and Kursk; the territories overtaken by the Red Army became satellite states of the Soviet Union.
The post-war division of Europe into capitalist and communist halves would lead to increased tensions with the United States-led Western Bloc, known as the Cold War. Stalin died in 1953 and was succeeded by Nikita Khrushchev, who in 1956 denounced Stalin and began the de-Stalinization; the Cuban Missile Crisis occurred during Khrushchev's rule, among the many factors that led to his downfall in 1964. In the early 1970s, there was a brief détente of relations with the United States, but tensions resumed with the Soviet–Afghan War in 1979. In 1985, the last Soviet premier, Mikhail Gorbachev, sought to reform and liberalize the economy through his policies of glasnost and perestroika, which caused political instability. In 1989, Soviet satellite states in Eastern Europe overthrew their respective communist governments; as part of an attempt to prevent the country's dissolution due to rising nationalist and separatist movements, a referendum was held in March 1991, boycotted by some republics, that resulted in a majority of participating citizens voting in favor of preserving the union as a renewed federation.
Gorbachev's power was diminished after Russian President Boris Yeltsin's high-profile role in facing down a coup d'état attempted by Communist Party hardliners. In late 1991, Gorbachev resigned and the Supreme Soviet of the Soviet Union met and formally dissolved the Soviet Union; the remaining 12 constituent republics emerged as independent post-Soviet states, with the Russian Federation—formerly the Russian SFSR—assuming the Soviet Union's rights and obligations and being recognized as the successor state. The Soviet Union was a powerhouse of many significant technological achievements and innovations of the 20th century, including the world's first human-made satellite, the first humans in space and the first probe to land on another planet, Venus; the country had the largest standing military in the world. The Soviet Union was recognized as one of the five nuclear weapons states and possessed the largest stockpile of weapons of mass destruction, it was a founding permanent member of the United Nations Security Council as well as a member of the Organization for Security and Co-operation in Europe, the World Federation of Trade Unions and the leading member of the Council for Mutual Economic Assistance and the Warsaw Pact.
The word "Soviet" is derived from a Russian word сове́т meaning council, advice, harmony and all deriving from the proto-Slavic verbal stem of vět-iti, related to Slavic věst, English "wise", the root in "ad-vis-or", or the Dutch weten. The word sovietnik means "councillor". A number of organizations in Russian history were called "council". For example, in the Russian Empire the State Council, which functioned from 1810 to 1917, was referred to as a Council of Ministers after the revolt of 1905. During the Georgian Affair, Vladimir Lenin envisioned an expression of Great Russian ethnic chauvinism by Joseph Stalin and his supporters, calling for these nation-states to join Russia as semi-independent parts of a greater union, which he named as the Union of Soviet Republics of Europe and Asia. Stalin resisted the proposal, but accepted it, although with Lenin's agreement changed the name of the newly proposed sta
Reactive armour is a type of vehicle armour that reacts in some way to the impact of a weapon to reduce the damage done to the vehicle being protected. It is most effective in protecting against shaped charges and specially hardened kinetic energy penetrators; the most common type is explosive reactive armour, but variants include self-limiting explosive reactive armour, non-energetic reactive armour, non-explosive reactive armour, electric reactive armour. NERA and NxRA modules can withstand multiple hits, unlike ERA and SLERA, but a second hit in the same location may penetrate any of those. All anti-tank munitions work by piercing the armour and killing the crew inside, disabling vital mechanical systems, or both. Reactive armour can be defeated with multiple hits in the same place, as by tandem-charge weapons, which fire two or more shaped charges in rapid succession. Without tandem charges, hitting the same spot twice is much more difficult; the idea of counterexplosion in armour was first proposed by the Scientific Research Institute of Steel in 1949 in the USSR by academician Bogdan Vjacheslavovich Voitsekhovsky.
The first pre-production models were produced during the 1960s. However, insufficient theoretical analysis during one of the tests resulted in all of the prototype elements being blown up. For a number of reasons, including the accident, as well as a belief that Soviet tanks had sufficient armour, the research was ended. No more research was conducted until 1974 when the Ministry of the Defensive Industry announced a contest to find the best tank protection project. A West German researcher, Manfred Held carried out similar work with the IDF in 1967–69. Reactive armour created on the basis of the joint research was first installed on Israeli tanks during the 1982 Lebanon war and was judged effective. An element of explosive reactive armour is made out of a sheet or slab of high explosive sandwiched between two plates metal, called the reactive or dynamic elements. On attack by a penetrating weapon, the explosive detonates, forcibly driving the metal plates apart to damage the penetrator. Against a shaped charge, the projected plates disrupt the metallic jet penetrator providing a greater path-length of material to be penetrated.
Against a kinetic energy penetrator, the projected plates serve to break up the rod. The disruption is attributed to two mechanisms. First, the moving plates change the effective velocity and angle of impact of the shaped charge jet, reducing the angle of incidence and increasing the effective jet velocity versus the plate element. Second, since the plates are angled compared to the usual impact direction of shaped charge warheads, as the plates move outwards the impact point on the plate moves over time, requiring the jet to cut through fresh plates material; this second effect increases the effective plate thickness during the impact. To be effective against kinetic energy projectiles, ERA must use much thicker and heavier plates and a correspondingly thicker explosive layer; such "heavy ERA," such as the Soviet-developed Kontakt-5, can break apart a penetrating rod, longer than the ERA is deep, again reducing penetration capability. An important aspect of ERA is the detonation speed of its explosive element.
A more brisant explosive and greater plate velocity will result in more plate material being fed into the path of the oncoming jet increasing the plate's effective thickness. This effect is pronounced in the rear plate receding away from the jet, which triples in effective thickness with double the velocity. ERA counters explosively forged projectiles, as produced by a shaped charge; the counter-explosion must disrupt the incoming projectile so that its momentum is distributed in all directions rather than towards the target diminishing its effectiveness. Explosive reactive armour has been valued by the Soviet Union and its now-independent component states since the 1980s, every tank in the eastern-European military inventory today has either been manufactured to use ERA or had ERA tiles added to it, including the T-55 and T-62 tanks built forty to fifty years ago, but still used today by reserve units; the U. S. Army uses reactive armour on its Abrams tanks as part of the TUSK package and on Bradley vehicles and the Israelis use it on their American built M60 tanks.
ERA tiles are used as add-on armour to the portions of an armoured fighting vehicle that are most to be hit the front of the hull and the front and sides of the turret. Their use requires that a vehicle be heavily armoured to protect itself and its crew from the exploding ERA. A further complication to the use of ERA is the inherent danger to anyone near the tank when a plate detonates, disregarding that a high explosive anti-tank warhead explosion would cause great danger to anyone near the tank. Although ERA plates are intended only to bulge following detonation, the combined energy of the ERA explosive, coupled with the kinetic or explosive energy of the projectile, will cause explosive fragmentation of the plate; the explosion of an ERA plate creates a significant amount of shrapnel, bystanders are in grave danger of fatal injury. Thus, infantry must operate some distance from vehicles protected by ERA in combined arms operations. NERA and NxRA operate to explosive reactive armour, but without the explosive liner.
Two metal plates sandwich an inert liner, such as rubber. When struck by a shaped charge's metal jet, some of the impact energy is dissipated into the in
In modern language, a missile known as a guided missile, is a guided self-propelled system, as opposed to an unguided self-propelled munition, referred to as a rocket. Missiles have four system components: targeting or missile guidance, flight system and warhead. Missiles come in types adapted for different purposes: surface-to-surface and air-to-surface missiles, surface-to-air missiles, air-to-air missiles, anti-satellite weapons. All known existing missiles are designed to be propelled during powered flight by chemical reactions inside a rocket engine, jet engine, or other type of engine. Non-self-propelled airborne explosive devices are referred to as shells and have a shorter range than missiles. In ordinary British-English usage predating guided weapons, a missile is such as objects thrown at players by rowdy spectators at a sporting event; the first missiles to be used operationally were a series of missiles developed by Nazi Germany in World War II. Most famous of these are the V-1 flying bomb and V-2 rocket, both of which used a simple mechanical autopilot to keep the missile flying along a pre-chosen route.
Less well known were a series of anti-shipping and anti-aircraft missiles based on a simple radio control system directed by the operator. However, these early systems in World War II were only built in small numbers. Guided missiles have a number of different system components: Guidance system Targeting system Flight system Engine Warhead The most common method of guidance is to use some form of radiation, such as infrared, lasers or radio waves, to guide the missile onto its target; this radiation may emanate from the target, it may be provided by the missile itself, or it may be provided by a friendly third party. The first two are known as fire-and-forget as they need no further support or control from the launch vehicle/platform in order to function. Another method is to use a TV guidance, with a visible light or infrared picture produced in order to see the target; the picture may be used either by a human operator who steering the missile onto its target or by a computer doing much the same job.
One of the more bizarre guidance methods instead used a pigeon to steer a missile to its target. Some missiles have a home-on-jam capability to guide itself to a radar-emitting source. Many missiles use a combination of two or more of the methods to improve accuracy and the chances of a successful engagement. Another method is to target the missile by knowing the location of the target and using a guidance system such as INS, TERCOM or satellite guidance; this guidance system guides the missile by knowing the missile's current position and the position of the target, calculating a course between them. This job can be performed somewhat crudely by a human operator who can see the target and the missile and guide it using either cable- or radio-based remote control, or by an automatic system that can track the target and the missile. Furthermore, some missiles use initial targeting, sending them to a target area, where they will switch to primary targeting, using either radar or IR targeting to acquire the target.
Whether a guided missile uses a targeting system, a guidance system or both, it needs a flight system. The flight system uses the data from the targeting or guidance system to maneuver the missile in flight, allowing it to counter inaccuracies in the missile or to follow a moving target. There are two main systems: aerodynamic maneuvering. Missiles are powered by an engine either a type of rocket engine or jet engine. Rockets are of the solid propellant type for ease of maintenance and fast deployment, although some larger ballistic missiles use liquid-propellant rockets. Jet engines are used in cruise missiles, most of the turbojet type, due to its relative simplicity and low frontal area. Turbofans and ramjets are the only other common forms of jet engine propulsion, although any type of engine could theoretically be used. Long-range missiles may have multiple engine stages in those launched from the surface; these stages may all be of similar types or may include a mix of engine types − for example, surface-launched cruise missiles have a rocket booster for launching and a jet engine for sustained flight.
Some missiles may have additional propulsion from another source at launch. Missiles have one or more explosive warheads, although other weapon types may be used; the warheads of a missile provide its primary destructive power. Warheads are most of the high explosive type employing shaped charges to exploit the accuracy of a guided weapon to destroy hardened targets. Other warhead types include submunitions, nuclear weapons, biological or radiological weapons or kinetic energy penetrators. Warheadless missiles are used for testing and training purposes. Missiles are categorized by their launch platform and intended target. In broadest terms, these will either be surface or air, t
South Korea the Republic of Korea, is a country in East Asia, constituting the southern part of the Korean Peninsula and lying to the east of the Asian mainland. The name Korea is derived from Goguryeo, one of the great powers in East Asia during its time, ruling most of the Korean Peninsula, parts of the Russian Far East and Inner Mongolia, under Gwanggaeto the Great. South Korea has a predominantly mountainous terrain, it comprises an estimated 51.4 million residents distributed over 100,363 km2. Its capital and largest city is Seoul, with a population of around 10 million. Archaeology indicates that the Korean Peninsula was inhabited by early humans starting from the Lower Paleolithic period; the history of Korea begins with the foundation of Gojoseon in 2333 BCE by the mythic king Dangun, but no archaeological evidence and writing was found from this period. The Gija Joseon was purportedly founded in 11th century BCE, its existence and role has been controversial in the modern era; the written historical record on Gojoseon was first mentioned in Chinese records in the early 7th century BCE.
Following the unification of the Three Kingdoms of Korea under Unified Silla in CE 668, Korea was subsequently ruled by the Goryeo dynasty and the Joseon dynasty. It was annexed by the Empire of Japan in 1910. At the end of World War II, Korea was divided into Soviet and U. S. zones of occupations. A separate election was held in the U. S. zone in 1948 which led to the creation of the Republic of Korea, while the Democratic People's Republic of Korea was established in the Soviet zone. The United Nations at the time passed a resolution declaring the ROK to be the only lawful government in Korea; the Korean War began in June 1950. The war lasted three years and involved the U. S. China, the Soviet Union and several other nations; the border between the two nations remains the most fortified in the world. Under long-time military leader Park Chung-hee, the South Korean economy grew and the country was transformed into a G-20 major economy. Military rule ended in 1987, the country is now a presidential republic consisting of 17 administrative divisions.
South Korea is a developed country and a high-income economy, with a "very high" Human Development Index, ranking 22nd in the world. The country is considered a regional power and is the world's 11th largest economy by nominal GDP and the 12th largest by PPP as of 2010. South Korea is a global leader in the industrial and technological sectors, being the world's 5th largest exporter and 8th largest importer, its export-driven economy focuses production on electronics, ships, machinery and robotics. South Korea is a member of the ASEAN Plus mechanism, the United Nations, Uniting for Consensus, G20, the WTO and OECD and is a founding member of APEC and the East Asia Summit; the name Korea derives from the name Goryeo. The name Goryeo itself was first used by the ancient kingdom of Goguryeo in the 5th century as a shortened form of its name; the 10th-century kingdom of Goryeo succeeded Goguryeo, thus inherited its name, pronounced by the visiting Persian merchants as "Korea". The modern spelling of Korea first appeared in the late 17th century in the travel writings of the Dutch East India Company's Hendrick Hamel.
Despite the coexistence of the spellings Corea and Korea in 19th century publications, some Koreans believe that Imperial Japan, around the time of the Japanese occupation, intentionally standardised the spelling on Korea, making Japan appear first alphabetically. After Goryeo was replaced by Joseon in 1392, Joseon became the official name for the entire territory, though it was not universally accepted; the new official name has its origin in the ancient country of Gojoseon. In 1897, the Joseon dynasty changed the official name of the country from Joseon to Daehan Jeguk; the name Daehan, which means "Great Han" derives from Samhan, referring to the Three Kingdoms of Korea, not the ancient confederacies in the southern Korean Peninsula. However, the name Joseon was still used by Koreans to refer to their country, though it was no longer the official name. Under Japanese rule, the two names Han and Joseon coexisted. There were several groups who fought for independence, the most notable being the Provisional Government of the Republic of Korea.
Following the surrender of Japan, in 1945, the Republic of Korea was adopted as the legal English name for the new country. Since the government only controlled the southern part of the Korean Peninsula, the informal term South Korea was coined, becoming common in the Western world. While South Koreans use Han to refer to the entire country, North Koreans and ethnic Koreans living in China and Japan use the term Joseon as the name of the country; the Korean name "Daehan Minguk" is sometimes used by South Koreans as a metonym to refer to the Korean ethnicity as a whole, rather than just the South Korean state. The history of Korea begins with the founding of Joseon in 2333 BCE by Dangun, according to Korea's foundation mythology. Gojoseon expanded until it controlled parts of Manchuria. Gija Joseon was purportedly founded in the 12th century BC, but its existence and role have been controversial in the modern era. In 108 BCE, the Han dynasty defeated Wiman Joseon and installed four commanderies in the n
K2 Black Panther
The K2 Black Panther is a next generation South Korean main battle tank designed by the South Korean Agency for Defense Development and manufactured by Hyundai Rotem. Developed as modern main battle tank that will replace most of the remaining M48 Patton tanks and complement the K1 series of main battle tanks fielded by the South Korean military, the K2 Black Panther combines an auto-loaded 55 calibre 120 mm main gun, advanced composite armour along with hard and soft-kill active protection systems. Mass production commenced in 2013 and the first K2s were deployed with the armed forces in June 2014; the K2 costs over US$8.5 million per unit, making it one of the most expensive main battle tanks in service. In 1995, the South Korean Agency for Defense Development was given the task of developing a modern armored fighting vehicle based upon South Korean state-of-the-art domestic technologies, it was intended for this development program to further modernize the South Korean army, despite the superior capability of existing K1 and K1A1 designs versus existing North Korean tanks, most of which are aging T-55s and Type 59s.
Emphasis upon indigenous technologies would allow the proposed vehicle to enter the export market without licensing difficulties. Early design variants included a version with an unmanned turret, scrapped in favor of manned turret designs, it was planned for the vehicle to be equipped with Rheinmetall's experimental 140 mm smoothbore gun, though this had to be abandoned when Rheinmetall ceased development upon the rationale that its current weapon, the 120 mm/L55 would be more than adequate to counter prospective armored threats for the foreseeable future. The K2 was subsequently reconfigured for the 120 mm/L55, though it is capable of mounting the 140 mm gun with minimum modifications should the need arise; the design became production-ready in 2006, following 11 years in development and a research budget expenditure of US$230 million, entered the production phase on March 2, 2007 in Changwon, South Korea. It was planned that the K2 would feature a domestically-designed powerpack, based upon the German-designed MTU-890, comprising a Doosan Infracore Corporation 1,500 horsepower 12-cylinder diesel engine and a S&T Dynamics transmission.
However, this encountered recurrent technical trouble in testing, leading to a delay in operational deployment of the K2 for 2 years. In March 2011, South Korea's Defense Acquisition Program Administration announced that mass production of the K2, which the Army was expecting to deploy in 2012, would not happen due to problems concerning its engine and transmission. In April 2012, DAPA announced that due to ongoing issues with the reliability and durability of the domestically-produced powerpack, the first 100 production K2s would use German-made MTU powerpack and that service entry would be delayed until March 2014; when compared to the K1A1 tank, the K2's main gun reloads quicker and reaches targets faster. Although both are 120 mm, the K2's barrel is 1.3 m longer, resulting in a higher muzzle velocity of 1,400 m/s for greater accuracy and armor penetration. Other features include the tank's ability to cross a 4 m -deep river, a posture control function that can lower its height by 40 cm, a laser warning system that turns the turret towards the source of hostile fire instantaneously.
The first 15 K2 Black Panther tanks were put into service in June 2014. Faulty indigenous engines and transmissions halted production, but the lowering of required acceleration performance allowed it to enter service; the powerpack will be produced locally, but until that occurs the K2 employs German-made MTU power plants which makes possible the deployment of around 100 vehicles by 2017. Tanks under the second contract, after the first 100 models, were to be built with the domestic Doosan DST 1,500 hp engine and S&T Dynamics automatic transmission, beginning delivery in late 2016. Hyundai Rotem signed a contract from the second batch of 106 K2 tanks in December 2014, but the vehicles continued to have powerplant issues due to the S&T Dynamics transmission failing durability tests. In February 2018, DAPA announced the second batch would have a "hybrid" powerpack consisting of the locally developed engine with the German RENK transmission system, allowing them to start entering service in 2019.
An additional contract for the production of a third batch of about 110 K2s is to follow within the next several years. The Black Panther is armed with a 120mm L/55 smoothbore gun indigenously developed by Hyundai Wia; this is complemented by an autoloader, similar to that designed for the Leclerc tank. The ammunition for the main gun is loaded in a 16-shell magazine; the tank has a total ammunition capacity of 40 rounds for its main armament. Secondary weapons include a 12.7 mm K6 Machine Gun heavy machine gun and a 7.62 mm coaxial machine gun. The K2 is equipped with an advanced fire-control system linked to an Extremely High Frequency radar system deployed on the frontal arc of the turret, along with a traditional laser rangefinder and crosswind sensor; the system is capable of a "lock-on" mode, which can acquire and track specific targets up to a range of 9.8 km using a thermographic camera. This allows the crew to fire while moving as well as engage low-flying aircraft; the fire-control system is linked to an advanced gun stabilizer and trigger-delay mechanism to optimise accuracy while moving in uneven terrain.
If the trigger on the main gun is pulled at the same time the tank encounters an irregularity in the terrain
Radar is a detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, spacecraft, guided missiles, motor vehicles, weather formations, terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna and a receiver and processor to determine properties of the object. Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the object's location and speed. Radar was developed secretly for military use by several nations in the period before and during World War II. A key development was the cavity magnetron in the UK, which allowed the creation of small systems with sub-meter resolution; the term RADAR was coined in 1940 by the United States Navy as an acronym for RAdio Detection And Ranging The term radar has since entered English and other languages as a common noun, losing all capitalization.
The modern uses of radar are diverse, including air and terrestrial traffic control, radar astronomy, air-defense systems, antimissile systems, marine radars to locate landmarks and other ships, aircraft anticollision systems, ocean surveillance systems, outer space surveillance and rendezvous systems, meteorological precipitation monitoring and flight control systems, guided missile target locating systems, ground-penetrating radar for geological observations, range-controlled radar for public health surveillance. High tech radar systems are associated with digital signal processing, machine learning and are capable of extracting useful information from high noise levels. Radar is a key technology that the self-driving systems are designed to use, along with sonar and other sensors. Other systems similar to radar make use of other parts of the electromagnetic spectrum. One example is "lidar". With the emergence of driverless vehicles, Radar is expected to assist the automated platform to monitor its environment, thus preventing unwanted incidents.
As early as 1886, German physicist Heinrich Hertz showed that radio waves could be reflected from solid objects. In 1895, Alexander Popov, a physics instructor at the Imperial Russian Navy school in Kronstadt, developed an apparatus using a coherer tube for detecting distant lightning strikes; the next year, he added a spark-gap transmitter. In 1897, while testing this equipment for communicating between two ships in the Baltic Sea, he took note of an interference beat caused by the passage of a third vessel. In his report, Popov wrote that this phenomenon might be used for detecting objects, but he did nothing more with this observation; the German inventor Christian Hülsmeyer was the first to use radio waves to detect "the presence of distant metallic objects". In 1904, he demonstrated the feasibility of detecting a ship in dense fog, but not its distance from the transmitter, he obtained a patent for his detection device in April 1904 and a patent for a related amendment for estimating the distance to the ship.
He got a British patent on September 23, 1904 for a full radar system, that he called a telemobiloscope. It operated on a 50 cm wavelength and the pulsed radar signal was created via a spark-gap, his system used the classic antenna setup of horn antenna with parabolic reflector and was presented to German military officials in practical tests in Cologne and Rotterdam harbour but was rejected. In 1915, Robert Watson-Watt used radio technology to provide advance warning to airmen and during the 1920s went on to lead the U. K. research establishment to make many advances using radio techniques, including the probing of the ionosphere and the detection of lightning at long distances. Through his lightning experiments, Watson-Watt became an expert on the use of radio direction finding before turning his inquiry to shortwave transmission. Requiring a suitable receiver for such studies, he told the "new boy" Arnold Frederic Wilkins to conduct an extensive review of available shortwave units. Wilkins would select a General Post Office model after noting its manual's description of a "fading" effect when aircraft flew overhead.
Across the Atlantic in 1922, after placing a transmitter and receiver on opposite sides of the Potomac River, U. S. Navy researchers A. Hoyt Taylor and Leo C. Young discovered that ships passing through the beam path caused the received signal to fade in and out. Taylor submitted a report, suggesting that this phenomenon might be used to detect the presence of ships in low visibility, but the Navy did not continue the work. Eight years Lawrence A. Hyland at the Naval Research Laboratory observed similar fading effects from passing aircraft. Before the Second World War, researchers in the United Kingdom, Germany, Japan, the Netherlands, the Soviet Union, the United States, independently and in great secrecy, developed technologies that led to the modern version of radar. Australia, New Zealand, South Africa followed prewar Great Britain's radar development, Hungary generated its radar technology during the war. In France in 1934, following systematic studies on the split-anode magnetron, the research branch of the Compagnie Générale de Télégraphie Sans Fil headed by Maurice Ponte with Henri Gutton, Sylvain Berline and M. Hugon, began developing an obstacle-locatin
Multiple rocket launcher
A multiple rocket launcher or multiple launch rocket system is a type of rocket artillery system. Rockets have different capabilities than artillery, like longer range and different payloads considerably larger warheads than a sized artillery platform or multiple warheads. Unguided rocket artillery is notoriously slow to reload compared to artillery. To overcome this rockets are combined in systems that can launch multiple rockets simultaneously. Modern rockets can use GPS or inertial guidance to combine the advantages of rockets with high accuracy; the first multiple rocket launchers were made during the mediaeval Chinese Song dynasty. It was designed to launch multiple rocket arrows from a gunpowder box; these appeared in an expanded version, in the Joseon Dynasty of Korea where they were used with great effectiveness against the Japanese invasions of 1592–98, most notably the Battle of Haengju. In parallel with Song Chinese development of guns and cannons the Song military invested great efforts in producing military rockets, including multiple rocket launchers mounted on wheelbarrows.
Multiple rocket launchers evolved from Chinese fire lances when the Song military favored multiple rocket launchers that fired up to 100 small fire-arrow rockets after the Mongol siege of Kaifeng. The typical powder section of such an arrow-rocket was 1/3 to 1/2 ft long. Bamboo arrow shafts varied from 1.5 ft to 2.5 ft long and the striking distance reached 300 to 400 paces. The Chinese enhanced rocket tips with poison and made sure that the launchers were mobile. Song Chinese rocket designers designed multiple rocket launchers that could be carried and operated by a single soldier. European armies preferred large single-launch rockets prior to World War II. Napoleonic armies of both sides followed British adoption of Mysore Army; these were explosive steel-cased bombardment rockets with minimal launchers. European navies developed naval multiple launcher mounts with improving explosive rockets for light and coastal vessels; these weapons were replaced by conventional light artillery during the late nineteenth century.
The first self-propelled multiple rocket launchers — and arguably the most famous — were the Soviet BM-13 Katyusha, first used during World War II and exported to Soviet allies afterwards. They were simple systems; this set the template for modern multiple rocket launchers. The Americans mounted tubular launchers atop M4 Sherman tanks to create the T34 Calliope rocket launching tank, only used in small numbers, as their closest equivalent to the Katyusha; the Germans began using a towed six-tube multiple rocket launcher during World War II, the Nebelwerfer called the "Screaming Mimi" by the Allies. The system was developed prior to the war to skirt the limitations of the treaty of Versailles. In the war the 15cm Nebelwerfer 41 was mounted on modified Opel Maultier "Mule" halftracks becoming the Panzerwerfer 42 4/1. Another version produced in limited numbers towards the end of the war was a conversion of sWS "heavy military transport" halftrack to a similar configuration as the Panzerwerfer 42 4/1 mounting the 10-barreled 15cm Nebelwerfer.
Another German halftrack MRL system was inspired by the Russian BM-13. Keeping the Soviet 82mm rocket calibre as well as the launch and rocket stabilisation designs it was developed into a system of 2 rows of 12 guide rails mounted to the Maultier chassis; this vehicle was designated as the 8cm Raketen Vielfachwerfer "8cm multiple rocket launcher". As the launch system was inspired by and looked similar to the BM-13 which the Germans had nicknamed "Stalin-Orgel" or "Stalin-Organ" the Vielfachwerfer soon became known as the "Himmler-Orgel" or "Himmler-Organ" There are two main types of multiple rocket launchers: With tubes or pipes, in modern times made of steel - non removable from launcher, with options to be reloaded in on the battlefield with rockets loaded manually or semi-automatically; this was the most usual type until the 21st century. It is more convenient for battlefield usage because it does not require special tools to reload modules and test them before using them on launchers as with other types.
With containers, pods or modules that can be removed from the launcher and replaced with same or different types of rockets and calibres. They are reloaded at factory or within specially-equipped army workshops; these are more modern types of weapons as they are not related to just one type of rocket and give more options to commanders on field to deal with different tactical situations using different types of rockets or to reload. They are easier to upgrade for different/new types of rockets. Simple MRL types still have a reputation of having a devastating morale effect on ill-disciplined or shaken troops; the material effect depends on circumstances, as well-covered field fortifications may provide reasonable protection. MRL are still unable properly to engage reverse slope positions in mountain warfare because it is more difficult to determine the trajectory compared to that of a howitzer by adding or removing propellant increments. Simple MRL rocket types have a rather long minimum firing range for the same reason.
An approach to lessen this limit is the addition of drag rings to the rocket nose. The increased drag slows the rocket down relative to a clean configuration and creates a less flat trajectory. Pre-packaged MRL munitions such as those forMLRS do not offer this option but some MRL types with individually-lo