1.
Swedish Air Force
–
The Swedish Air Force is the air force branch of the Swedish Armed Forces. The Swedish Air Force was created on July 1,1926 when the units of the Army. Because of the international tension during the 1930s the Air Force was reorganized and expanded from four to seven squadrons. When World War II broke out in 1939 further expansion was initiated, although Sweden never entered the war, a large air force was considered necessary to ward off the threat of invasion and to resist pressure through military threats from the great powers. By 1945 the Swedish Air Force had over 800 combat-ready aircraft, a major problem for the Swedish Air Force during World War II was the lack of fuel. Sweden was surrounded by countries at war and could not rely on imported oil, instead domestic oil shales were heated to produce the needed petrol. The Swedish Air Force underwent a rapid modernization from 1945 and it was no longer politically acceptable to equip it with second-rate models. When the Saab 29 Tunnan fighter was introduced around 1950, Sweden suddenly had planes that were equal to the best of the Royal Air Force, the Soviet Unions VVS, during the 1950s the air force started to build road bases after an idea taken from Germany. Built under the BASE60 distributed airfield scheme, the bases were ordinary highways constructed in such a way that they could serve as landing strips. In the early eighties road number 44 was rebuilt to four short runways. Along the road a number of turn-around-sites for rearming and refueling were built. These short runways are used today for training, landing and taking off with Gripen. During the Cold War large amounts of money were spent on the Swedish Air Force, in 1957 Sweden had the worlds fourth most powerful air force, with about 1000 modern planes in front-line service. During the 1950s, it introduced fighters such as the Saab J29 Tunnan, Saab A32 Lansen, in June 1952 the Swedish Air Force lost two aircraft on Cold War operations, in what became known as the Catalina affair. A signals intelligence Douglas DC-3 was intercepted by Soviet MiG-15s over the Baltic, a PBY Catalina rescue seaplane was then also downed, the five-man crew being rescued from the sea by a freighter. When the Soviet Union attacked Finland in November 1939, Sweden came to its neighbours assistance in most ways short of joining the war outright, a Swedish volunteer infantry brigade and a volunteer air squadron fought in northern Finland in January till March 1940. The squadron was designated F19 and consisted of 12 Gloster Gladiator fighters, the Swedish Air Force saw combat as part of the United Nations peace-keeping mission ONUC during the Congo Crisis in 1961 to 1964. It established an air wing, F22, equipped with a dozen semi-obsolete Saab 29 Tunnans
2.
Fighter aircraft
–
A fighter aircraft is a military aircraft designed primarily for air-to-air combat against other aircraft, as opposed to bombers and attack aircraft, whose main mission is to attack ground targets. The hallmarks of a fighter are its speed, maneuverability, many fighters have secondary ground-attack capabilities, and some are designed as dual-purpose fighter-bombers, often aircraft that do not fulfill the standard definition are called fighters. This may be for political or national security reasons, for advertising purposes, a fighters main purpose is to establish air superiority over a battlefield. Since World War I, achieving and maintaining air superiority has been considered essential for victory in conventional warfare, the word fighter did not become the official English-language term for such aircraft until after World War I. In the British Royal Flying Corps and Royal Air Force these aircraft were referred to as scouts into the early 1920s, the U. S. Army called their fighters pursuit aircraft from 1916 until the late 1940s. In most languages a fighter aircraft is known as a hunter, exceptions include Russian, where a fighter is an истребитель, meaning exterminator, and Hebrew where it is matose krav. As a part of nomenclature, a letter is often assigned to various types of aircraft to indicate their use. In Russia I was used, while the French continue to use C and this has always been the case, for instance the Sopwith Camel and other fighting scouts of World War I performed a great deal of ground-attack work. Several aircraft, such as the F-111 and F-117, have received fighter designations but had no fighter capability due to political or other reasons, the F-111B variant was originally intended for a fighter role with the U. S. Navy, but it was cancelled. This blurring follows the use of fighters from their earliest days for attack or strike operations against ground targets by means of strafing or dropping small bombs, versatile multirole fighter-bombers such as the F/A-18 Hornet are a less expensive option than having a range of specialized aircraft types. An interceptor is generally an aircraft intended to target bombers and so often trades maneuverability for climb rate, fighters were developed in World War I to deny enemy aircraft and dirigibles the ability to gather information by reconnaissance. Early fighters were very small and lightly armed by later standards, and most were built with a wooden frame, covered with fabric. As control of the airspace over armies became increasingly important all of the major powers developed fighters to support their military operations, between the wars, wood was largely replaced by steel tubing, then aluminium tubing, and finally aluminium stressed skin structures began to predominate. By World War II, most fighters were all-metal monoplanes armed with batteries of guns or cannons. By the end of the war, turbojet engines were replacing piston engines as the means of propulsion, further increasing aircraft speed. Since the weight of the engine was so less than on piston engined fighters. This in turn required the development of ejection seats so the pilot could escape, in the 1950s, radar was fitted to day fighters, since pilots could no longer see far enough ahead to prepare for any opposition. Since then, radar capabilities have grown enormously and are now the method of target acquisition
3.
Saab Group
–
Saab Group is a Swedish aerospace and defence company, founded in 1937. From 1947 to 1990 it was the parent company of automobile manufacturer Saab Automobile, between 1968 and 1995 the company was in a merger with commercial vehicle manufacturer Scania-Vabis, known as Saab-Scania. The two were de-merged in 1995 by the new owners, Investor AB, despite the demerger, both Saab and Scania share the right to use the griffin logo, which originates from the coat of arms of the Swedish region of Scania. Svenska Aeroplan AB was founded in 1937 in Trollhättan, with the merger of Svenska Aero AB, the style Saab replaced SAAB around 1950. Originally manufacturing aircraft, the company sought ways in which to diversify its business, in the late 1940s the company began manufacturing cars at its Saab Automobile division, based in Trollhättan. The first car was the Saab 92, full-scale production started December 12,1949, in the late 1950s Saab ventured into the computer market with Datasaab. The company was a partly of the need to make a computer that would be small enough to mount in an aeroplane as navigational equipment. During the 1960s several computers were developed and sold to European countries, the aircraft computer was used in 1971 in the Viggen. The company was sold in 1975 to Sperry UNIVAC, while Saab retained its flight computer development, in May 1965, the company name was changed to Saab AB to reflect its broad range of activities. In 1968 Saab AB merged with the Swedish lorry, bus and heavy-duty diesel engine manufacturer Scania-Vabis, in 1990 General Motors bought 51 percent of the car division Saab Automobile, and acquired the rest a decade later. In 1991 Investor AB completed a buyout of Saab-Scania AB. Investor AB acquired all the shares in Saab-Scania for approximately SEK21 billion. Saab-Scania became a wholly owned subsidiary of Investor AB and the company was de-listed, in 1995 Saab-Scania was divided by Investor AB into two independent companies, de-merging into Scania AB and Saab AB. The intention by Investor AB was to broaden ownership in the two companies later, following the sale of 50% of the car division Saab Automobile AB to General Motors, the main reason behind the merger with lorry manufacturer Scania-Vabis in 1968 had disappeared. Saab Military Aircraft and British Aerospace formed in 1995 the joint venture company Saab-BAe Gripen AB, to manufacture, market and this co-operation was extended in 2001 with the formation of Gripen International for the same purpose. From 1998 until 2005 the largest shareholder in Saab was the British aerospace company BAE Systems, following its acquisition of a 35% stake from Investor AB by its predecessor, in January 2005, BAE Systems reduced its shareholding to 20%. Investor AB maintained a 20% share,16 November 1999, Saab announced its intention is to purchase Celsius AB and the acquisition was concluded by early March 2000. In December 2005 Saab joined the Dassault nEUROn project as a major partner, in October 2008 the company announced its intention to merge its operations with that of Simrad Optronics
4.
Austrian Air Force
–
The Austrian Air Force is a component part of the Austrian armed forces. The Austrian Air Force was formed in May 1955 by the victorious Allied powers, the Austrian State Treaty of 1955 committed Austria to permanent neutrality. Pilot training started out with a few Yak 11 Moose and Yak 18 Max aircraft donated by the Soviet Union, from 1970, Austria purchased a total of 40 Saab 105 lightweight multi-role aircraft with the intention to deploy them in trainer, reconnaissance, interception and ground attack roles. The Saab 105 remained in service as a trainer/surveillance aircraft, shortly after, the Draken saw their first major use in airspace interdiction starting 1991 during the Yugoslav Wars, when Yugoslav MiG-21 fighters crossed the Austrian border without permission. In one incident on 28 June a MiG-21 penetrated as far as Graz, following repeated border crossings by armed aircraft of the Yugoslav Peoples Army, changes were suggested to the standing orders for aircraft armament. Since 1955, Austrias armed forces had been forbidden to operate any guided missile system, including Air-to-air missiles, a higher performance model of the Sidewinder were purchased directly from the United States, deliveries began in 1995. French Mistral SAMs were purchased to add ground-based protection against air attack, the first Mistrals arrived in 1993 and final deliveries were concluded in 1996. The helicopter fleet includes Agusta-Bell 204s, AB-206s, and AB-212s, french-made Alouette IIIs are available for search-and-rescue tasks, including high mountain operations. The Bell OH-58 Kiowa, a helicopter, is mounted with a rapid-firing machine gun. Most of the helicopters, except the AB-212s, are becoming obsolete, after the 1999 Galtür Avalanche, it became apparent that the Austrian Air Forces helicopter complement were too few in numbers and too limited in design. Therefore, several US built UH-60 Blackhawk helicopters were purchased, to be used for transportation during disasters, in 2003 Austrias transport capability was improved when it purchased three C-130 Hercules from the Royal Air Force. These aircraft were needed for the demanding UN peacekeeping missions in which Austria played a role, in 2005, the Saab Draken fleet was retired, to be replaced by the Eurofighter Typhoon. Before the first delivery of Typhoons, F-5 Tiger II were leased from Switzerland as a stopgap measure, the Eurofighter purchase was subject to controversy in Austria, and became a political football for some time, but the 15th and final aircraft was delivered on 24 September 2009. Vogler Air Base Vogler Air Base, north of the town of Hörsching west of Linz, was built as a base for the German Luftwaffe 1938–1940. After the war the USAAF used the base, then named Camp McCauley – Hörsching and housing displaced persons, initially used exclusively by the ground forces, the first military aircraft, Yak-18 Max-A, arrived in 1957. The base was named for First Lieutenant Walter Vogler in 1967, the German-built base structures were used jointly by the military and civilian aviation until the 70s when construction of the new civilian area in the northern part of the base was finished. FH Vogler is the largest base of the Luftstreitkräfte and it houses Fliegerwerft 3, responsible for overhauls and maintenance of the C-130K Hercules and AB-212. Brumowski Air Base Fliegerhorst Brumowski, south of the town of Langenlebarn northwest of Vienna, was built as a base for the Luftwaffe 1938–1940
5.
Finnish Air Force
–
The Finnish Air Force, is one of the branches of the Finnish Defence Forces. Its peacetime tasks are airspace surveillance, identification flights, and production of readiness formations for wartime conditions, as a separate branch of the military, the Finnish Air Force was founded on 4 May 1928, having existed officially since 6 March 1918 as the Army Corps of Aviation. The first steps in the history of Finnish aviation were taken with Russian aircraft, the Russian military had a number of early designs stationed in the country, which until the Russian Revolution of 1917 had been part of the Russian Empire. Soon after the declaration of independence the Finnish Civil War erupted, Finlands White Guard, the Whites, managed to seize a few aircraft from the Russians, but were forced to rely on foreign pilots and aircraft. Sweden refused to send men and material, but individual Swedish citizens came to the aid of the Whites, the editor of the Swedish daily magazine Aftonbladet, Waldemar Langlet, bought a N. A. B. Albatros aircraft from the Nordiska Aviatik A. B. factory with funds gathered by the Finlands vänner organization and this aircraft, the first to arrive from Sweden, was flown via Haparanda on 25 February 1918 by Swedish pilots John-Allan Hygerth and Per Svanbäck. The aircraft made a stop at Kokkola and had to make a landing in Jakobstad when its engine broke down. It was later given the Finnish Air Force designation F.2, Swedish count Eric von Rosen gave the Finnish White government its second aircraft, a Thulin Typ D. Its pilot, Lieutenant Nils Kindberg, flew the aircraft to Vaasa on 6 March 1918, the von Rosen aircraft was given the designation F.1. The Finnish Air Force is one of the oldest air forces of the world – the RAF was founded as the first independent branch on 1 April 1918, von Rosen had painted his personal good luck charm on the Thulin Typ D aircraft. This charm – a blue swastika, the ancient symbol of the sun, the white circular background was created when the Finns tried to paint over the advertisement from the Thulin air academy. The swastika was officially taken into use after an order by Commander-in-Chief C. G. E. Mannerheim on 18 March 1918, the FAF changed its aircraft insignia after 1944, due to an Allied Control Commission decree prohibiting Fascist organizations and it resembling the 3rd Reichs swastika. The F.1 aircraft was destroyed in an accident, killing its crew, on 7 September 1920, two newly purchased Savoia flying boats crashed in the Swiss Alps en route to Finland, killing all on-board. This day has since been the day for fallen pilots. The Finnish Air Force assigns the numbers to its aircraft by assigning each type a two-letter code following by dash. The two-letter code usually refers to the manufacturer or model, such as HN for F/A-18 Hornet, DK for Saab 35 Draken. Most of the airbases that the Russians had left in Finland had been taken over by Whites after the Russian pilots had returned to Russia, the Reds were in possession of a few airbases and a few Russian aircraft, mainly amphibious aircraft. They had 12 aircraft in all, the Reds did not have any pilots themselves, so they hired some of the Russian pilots that had stayed behind
6.
Royal Danish Air Force
–
The Royal Danish Air Force is the aerial warfare force of Denmark and one of the four branches of the Danish Defence. Initially being components the Army and Navy, it was made a service in 1950. It main purpose, is to serve as enforcer of Danish airspace, the air force was led by Lieutenant General C. C. J. Førslev, who had served as colonel in the army. The national command was located at Værløse Air Base which also served as Command East, Royal Air Force volunteer and former member of the Free Norwegian Forces in England, Kaj Birksted, was appointed chief of the flying staff. Further, the East and West commands lacked experience and knowledge of the newly delivered Gloster Meteor, the Danish armed forces received 38 surplus Supermarine Spitfire H. F. Mk. One survived for a number of years in a childrens playground, the one surviving instructional airframe was later restored to depict the number 401 Spitfire Mk. This airplane is now preserved at Dansk Veteranflysamling at Stauning Airfield in Jylland, pilot training was initially based at Avnø from May 1946 until 1951, when the school were transferred to the U. S. under the Military Assistance Programme. The school at Avnø continued to conduct tests to choose the candidates for the American training programme, in 1947 the RDAF established a school for aircraft mechanics, based at Værløse Air Base. In 1951, the RDAF officers school was inaugurated at Rungstedlund north of Copenhagen, the air force received six F-84E Thunderjet and 238 F-84G Thunderjet as military aid from the US, and formed five new squadrons at Karup Air Base from 1952 to 1954. The rapid expansion caused problems as neither two-seaters nor flight simulators were available, to avoid further casualties the air force established a training squadron of two-seated T-33As in 1956 to train US-educated pilots to navigate under local weather conditions. Furthermore, squadron 722 was changed to function as rescue squadron in 1956 and was strengthened by seven Sikorsky S-55 helicopters in 1957, in 1962 the Royal Danish Armys four SAM batteries based on Nike missiles were transferred to the air force. In 1965 four batteries of Hawk missiles were deployed close to the Nike batteries to protect them from low altitude aircraft, in the 1960s and 1970s the RDAF operated a number of US financed Lockheed F-104G Starfighters, North American F-100D and F-100F Super Sabres, and several other types. In 1971 the Danish army created the Royal Danish Army Flying Service as the first air-unit outside the air force, since its creation in 1950 and it had observation helicopters and piston-engined artillery spotting aeroplanes. In 1977 the Danish Naval Air Squadron was extracted from squadron 722 to the Danish navy, in a joint arms purchase four NATO countries, Denmark, Norway, Netherlands, and Belgium introduced the General Dynamics F-16 Fighting Falcon as their common strike fighter in January 1980. The F-16 was later bought by additional NATO countries, Greece and Turkey, in 1982 the number of fighter aircraft was reduced by 12 units. General Dynamics F-16 is introduced to replace initially the F-100 and later the F-104G, the Royal Danish Naval Air Service is strengthened by eight Westland Lynx Mk.80 from 1980, replacing the Alouette III helicopters. As a supplement to the Greenland-based C-130s the air force purchases three Gulfstream G-III, in 1990 the Danish Army Air Corps purchases 12 Eurocopter Fennec lightweight attack helicopters to strengthen capabilities to perform expeditionary mission
7.
Supersonic aircraft
–
A supersonic aircraft is an aircraft able to fly faster than the speed of sound. Supersonic aircraft were developed in the half of the twentieth century and have been used almost entirely for research. Only two, Concorde and the Tupolev Tu-144, ever entered service for use as airliners. Fighter jets are the most common example of supersonic aircraft, the aerodynamics of supersonic flight is called compressible flow because of the compression associated with the shock waves or sonic boom created by any object travelling faster than sound. Aircraft flying at speeds above Mach 5 are often referred to as hypersonic aircraft, the first aircraft to fly supersonically in level flight was the American Bell X-1 experimental plane which was powered by a 6000-lb thrust rocket powered by liquid oxygen and ethyl alcohol. The majority of aircraft have been military or experimental aircraft. In the 1960s and 70s, many design studies for supersonic airliners were done, however political, environmental and economic obstacles and one fatal Concorde crash prevented them from being used to their full commercial potential and these aircraft are no longer flying. Supersonic flight brings with it substantial technical challenges, as the aerodynamics of flight are dramatically different from those of subsonic flight. In particular, aerodynamic drag rises sharply as the passes the transonic regime, requiring much greater engine power. To keep drag low, wing span must be limited, which reduces the aerodynamic efficiency when flying slowly. Since a supersonic aircraft must take off and land at a slow speed. However, swinging affects the longitudinal trim of the aircraft and the mechanism adds weight and cost. Another technique that has used is a delta-wing design, such as used on Concorde. This has the advantage that it can attain a high angle of attack at low speeds, other kinds of wings are the Short thin wing, Sweep back wing and the swept forward wing. Another problem is the heat generated by friction as the air flows over the aircraft, most supersonic designs use aluminium alloys such as Duralumin, which are cheap and easy to work but lose their strength quickly at high temperatures. This limits maximum speed to around Mach 2.2, some early supersonic aircraft, including the first, relied on rocket power to provide the necessary thrust, although rockets burn a lot of fuel and so flight times were short. Early turbojets were more fuel-efficient but did not have enough thrust, the invention of the afterburner, in which extra fuel is burned in the jet exhaust, made these mixed powerplant types obsolete. The turbofan engine passes additional cold air around the core, further increasing its fuel efficiency
8.
Saab 29 Tunnan
–
The Saab 29, colloquially called Flygande tunnan, was a Swedish fighter designed and manufactured by Saab in the 1940s. Despite its rotund appearance, from which its name derives, the J29 was a fast and it served effectively in both fighter and fighter-bomber roles into the 1970s. In the aftermath of the Second World War, it was decided that Sweden required an air defence utilising the newly developed jet propulsion technology. Accordingly, project JxR was initiated in the months of 1945. This led to a pair of proposals being issued by the Saab design team, the first of these, codenamed R101, was a cigar-shaped aircraft which bore a resemblance to the American Lockheed P-80 Shooting Star. The second design, which would later be picked as the winner, was the design, codenamed R1001. In order to make the wing as thin as possible, Saab elected to locate the retractable undercarriage upon the fuselage rather than upon the wings. For the reason of lateral stability during take-off and landing, automatically-locking leading edge slots, which were interconnected with the flaps, were also deemed necessary. In order to further test the design of the wing, it was decided to modify a single Saab Safir. The first final sketches of the aircraft, incorporating the new information, was drawn in January 1946, the originally envisioned powerplant for the type was the de Havilland Goblin turbojet engine. However, in December 1945, information on the newer and more powerful de Havilland Ghost engine became available, the structure employed a complicated mixture of stressed skin and heavy frames in order to meet conflicting requirements on space, strength, rigidity and accessibility. However, faults were encountered with the aileron servomotors which delayed the first flight of the first prototype, on 1 September 1948, the first of the Saab 29 prototypes conducted its maiden flight, which lasted for half an hour. Following the flight, Moore described the aircraft as being, on the ground an ugly duckling – in the air, because of the shape of its fuselage, the Saab J29 quickly received the nickname Flygande Tunnan, or Tunnan for short. While the demeaning nickname was not appreciated by SAAB, its shortform was eventually officially adopted, a total of four prototypes were built for the aircrafts test program. The first two lacked armaments, carrying heavy test equipment in their place instead, while the prototype was armed with four 20mm automatic guns. In 1948, production of the type commenced, in May 1951, from 1950 to 1956, at which point manufacturing was terminated, a total of 661 Tunnans were completed, making it the largest production run for any Saab aircraft. The Saab 29 Tunnan is a jet fighter, possessing the distinction of being the first Swedish aircraft to be specifically designed to use jet propulsion. The two-spar wing is a single piece structure attached to the fuselage by four bolts, the undercarriage was hydraulically retracted during flight and was designed to be suitable for landing upon rough grass airstrips
9.
Saab 32 Lansen
–
The Saab 32 Lansen was a two-seat, transonic military aircraft designed and manufactured by Saab from 1955 to 1960 for the Swedish Air Force. Three principal variants of the Lansen were built for attack, fighter, during its long operational life, the Saab 32 also served as an electronic warfare platform and target-tug aircraft. In Autumn 1946, the Saab company began internal studies aimed at developing a replacement aircraft for the Saab B 18/S18 as Swedens standard attack aircraft. On 20 December 1948, a phase one contract for the design and mock-up of the aircraft was issued. It had to be capable of being launched in any weather conditions, in response, Saab elected to develop a twin-seat aircraft with a low-mounted wing, and equipped with advanced electronics. The P1150 would break new grounds for the Swedish Air Force, being their first two-seat jet aircraft, Saab had initially envisaged powering the P1150 with the indigenously produced STAL Dovern turbojet engine.5, instead. The single Avon engine provided the Saab A 32A with a thrust to weight ratio of about 0, on 3 November 1952, the first P1150 prototype conducted its first flight. Triangular fences were added near the roots during flight testing in order to improve airflow when the aircraft was being flown at a high angle of attack. A small batch of P1150 prototypes completed design and evaluation trials with series production of the newly designated Saab 32 Lansen beginning in 1953, development work on the project was recorded as having involved more than 2,000,000 man-hours in total. These two models differed substantially from the first, the J32 B being fitted with a new engine for flight performance along with new navigation. On 7 January 1957, the first J32 B Lansen conducted its maiden flight, on 26 Match 1957, production of the Lansen continued until May 1960. The Saab 32 Lansen had a general arrangement, being one of the first aircraft in the world to be specifically developed to fly attack missions. From the outset, it was designed to provide support for the installation of electronic warfare. The aircraft could be armed with a total of four 20 mm cannon, as well as wing pylons for various calibers of rockets and assorted bombs. The J32 variant carried four 30 mm ADEN cannons while the A32 had an armament of four 20 mm Bofors m/49 cannon hidden under flaps in the nose. The J32 differed substantially from the variant, Saab describing it as to all intents a new aircraft, being fitted with a more powerful engine and newer armaments. The attack variant of the Lansen could carry up to two RB04 missiles, one underneath each wing, the fuselage of the Lansen was produced with a sleek, streamlined airframe with clean lines. The Lansen was the first aircraft on which every line had been a result of mathematical calculation
10.
Delta wing
–
The delta wing is a wing shaped in the form of a triangle. It is named for its similarity in shape to the Greek uppercase letter delta, triangular stabilizing fins for rockets were described ca. 1529-1556 by Conrad Haas and in the 17th century by Kazimierz Siemienowicz, the lifting delta wing was pioneered by Alexander Lippisch in Germany after World War I, initially using a very gentle angle so that the wing appeared almost straight. He flew the first tailless aircraft in 1931, followed by four improved designs. None of these designs were easy to handle at low speed, during World War II Lippisch studied a more advanced tailless delta wing of greater angle intended for high-speed and even supersonic flight, for use in interceptor aircraft. One progressed as far as a glider prototype, the British later developed jet aircraft based on the data from Lippisch, notably the Avro Vulcan strategic bomber and the Gloster Javelin fighter. In America Robert T. Jones, working at NACA during World War II, first published in January 1945, this approach differed from Lippischs earlier work on thick delta wings by combining a delta planform with a thin airfoil. This design proved to be superior and would form the basis of all practical supersonic deltas such as those first made by Convair. The tailless delta became a design for high-speed aircraft, and was used almost to the exclusion of other designs by Convair and by Dassault Aviation. The F-102 Delta Dagger and Douglas F4D Skyray were two of the first operational jet fighters with a delta wing when they entered service in 1956. The tailed delta configuration was adopted by the TsAGI, to take advantage of both high angle-of-attack flying capability and high speeds. It was used in the MiG-21 and Sukhoi Su-9/Su-11/15 fighters, built by the tens of thousands in several different communist countries, through the 1960s Saab AB developed a close-coupled canard delta configuration, with a delta foreplane just in front of and above the main delta wing. Patented in 1963, it first flew on the Viggen fighter in 1967, the close coupling modifies the airflow over the wing, most notably when flying at high angles of attack. In contrast to the classic tail-mounted elevators, the canards add to the lift, enabling the execution of extreme maneuvers. This configuration has become common on supersonic fighter aircraft. When supersonic transport aircraft were developed, the tailless delta wing was chosen for both the Anglo-French Concorde and the Soviet Tupolev Tu-144, the Tupolev first flying in 1968. Pure delta wings suffer from some undesirable characteristics, notably flow separation at high angles of attack and this originally limited them primarily to high-speed, high-altitude interceptor roles. Since then the design has been modified in different ways to overcome some of these problems
11.
Royal Swedish Air Force
–
The Swedish Air Force is the air force branch of the Swedish Armed Forces. The Swedish Air Force was created on July 1,1926 when the units of the Army. Because of the international tension during the 1930s the Air Force was reorganized and expanded from four to seven squadrons. When World War II broke out in 1939 further expansion was initiated, although Sweden never entered the war, a large air force was considered necessary to ward off the threat of invasion and to resist pressure through military threats from the great powers. By 1945 the Swedish Air Force had over 800 combat-ready aircraft, a major problem for the Swedish Air Force during World War II was the lack of fuel. Sweden was surrounded by countries at war and could not rely on imported oil, instead domestic oil shales were heated to produce the needed petrol. The Swedish Air Force underwent a rapid modernization from 1945 and it was no longer politically acceptable to equip it with second-rate models. When the Saab 29 Tunnan fighter was introduced around 1950, Sweden suddenly had planes that were equal to the best of the Royal Air Force, the Soviet Unions VVS, during the 1950s the air force started to build road bases after an idea taken from Germany. Built under the BASE60 distributed airfield scheme, the bases were ordinary highways constructed in such a way that they could serve as landing strips. In the early eighties road number 44 was rebuilt to four short runways. Along the road a number of turn-around-sites for rearming and refueling were built. These short runways are used today for training, landing and taking off with Gripen. During the Cold War large amounts of money were spent on the Swedish Air Force, in 1957 Sweden had the worlds fourth most powerful air force, with about 1000 modern planes in front-line service. During the 1950s, it introduced fighters such as the Saab J29 Tunnan, Saab A32 Lansen, in June 1952 the Swedish Air Force lost two aircraft on Cold War operations, in what became known as the Catalina affair. A signals intelligence Douglas DC-3 was intercepted by Soviet MiG-15s over the Baltic, a PBY Catalina rescue seaplane was then also downed, the five-man crew being rescued from the sea by a freighter. When the Soviet Union attacked Finland in November 1939, Sweden came to its neighbours assistance in most ways short of joining the war outright, a Swedish volunteer infantry brigade and a volunteer air squadron fought in northern Finland in January till March 1940. The squadron was designated F19 and consisted of 12 Gloster Gladiator fighters, the Swedish Air Force saw combat as part of the United Nations peace-keeping mission ONUC during the Congo Crisis in 1961 to 1964. It established an air wing, F22, equipped with a dozen semi-obsolete Saab 29 Tunnans
12.
Anti-aircraft warfare
–
Anti-aircraft warfare or counter-air defence is defined by NATO as all measures designed to nullify or reduce the effectiveness of hostile air action. They include ground-and air-based weapon systems, associated sensor systems, command and control arrangements and it may be used to protect naval, ground, and air forces in any location. However, for most countries the main effort has tended to be homeland defence, NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence as are initiatives to adapt air defence to the task of intercepting any projectile in flight, a surface-based air defence capability can also be deployed offensively to deny the use of airspace to an opponent. Until the 1950s, guns firing ballistic munitions ranging from 20 mm to 150 mm were the weapons, guided missiles then became dominant. The term air defence was probably first used by Britain when Air Defence of Great Britain was created as a Royal Air Force command in 1925. However, arrangements in the UK were also called anti-aircraft, abbreviated as AA, after the First World War it was sometimes prefixed by Light or Heavy to classify a type of gun or unit. Nicknames for anti-aircraft guns include AA, AAA or triple-A, an abbreviation of anti-aircraft artillery, ack-ack, NATO defines anti-aircraft warfare as measures taken to defend a maritime force against attacks by airborne weapons launched from aircraft, ships, submarines and land-based sites. In some armies the term All-Arms Air Defence is used for air defence by nonspecialist troops, other terms from the late 20th century include GBAD with related terms SHORAD and MANPADS. Anti-aircraft missiles are variously called surface-to-air missile, abbreviated and pronounced SAM, non-English terms for air defence include the German FlaK, whence English flak, and the Russian term Protivovozdushnaya oborona, a literal translation of anti-air defence, abbreviated as PVO. In Russian the AA systems are called zenitnye systems, in French, air defence is called DCA. The maximum distance at which a gun or missile can engage an aircraft is an important figure, however, many different definitions are used but unless the same definition is used, performance of different guns or missiles cannot be compared. For AA guns only the part of the trajectory can be usefully used. By the late 1930s the British definition was that height at which an approaching target at 400 mph can be engaged for 20 seconds before the gun reaches 70 degrees elevation. However, effective ceiling for heavy AA guns was affected by nonballistic factors, The maximum running time of the fuse, the capability of fire control instruments to determine target height at long range. The essence of air defence is to detect aircraft and destroy them. The critical issue is to hit a target moving in three-dimensional space, Air defence evolution covered the areas of sensors and technical fire control, weapons, and command and control. At the start of the 20th century these were very primitive or non-existent
13.
Dogfight
–
A dogfight, or dog fight, is an aerial battle between fighter aircraft, conducted at close range. Dogfighting first appeared during World War I, shortly after the invention of the airplane, until at least 1992, it was a component in every major war, despite beliefs after World War II that increasingly greater speeds and longer range weapons would make dogfighting obsolete. This differs from aerial warfare, which deals with the involved in planning and executing various missions. The term dogfight has been used for centuries to describe a melee, the term gained popularity during World War II although its origin in air combat can be traced to the latter years of World War I. Both men had orders to kill but neither wanted to harm the other so they exchanged multiple volleys of pistol fire. Dogfighting first emerged in World War I, ever since heavier than air flights became a reality in 1903, people had been trying to figure out how to use this new technology for warfare. Aircraft were initially used as observation vehicles, and early pilots gave little thought to aerial combat. The new airplanes proved their worth by spotting the hidden German advance on Paris in the month of the war. Enemy pilots at first simply exchanged waves, or shook their fists at each other, due to weight restrictions, only small weapons could be carried on board. Intrepid pilots decided to interfere with enemy reconnaissance by improvised means, including throwing bricks, grenades and sometimes rope, pilots quickly began firing hand-held guns at enemy planes, such as pistols and carbines. The Austro-Hungarian pilot initially waved, and Tomić reciprocated, the Austro-Hungarian pilot then fired at Tomić with his revolver. Tomić managed to escape, and within weeks, all Serbian and Austro-Hungarian planes were fitted with machine-guns. In August 1914, Staff-Captain Pyotr Nesterov, from Russia, became the first pilot to ram his plane into an enemy spotter aircraft, in October 1914, an airplane was shot down by a hand gun from another plane for the first time over Rheims, France. Once machine guns were mounted to the airplane, either on a mounting or higher on the wings of early biplanes. The biggest problem was mounting a gun onto an aircraft so that it could be fired forward, through the propeller. Roland Garros solved this problem by mounting steel deflector wedges to the propeller of a Morane Saulnier monoplane and he achieved three kills, but was forced down due to engine failure down behind enemy lines, and captured before he could destroy his plane by burning it. The wreckage was brought to Anthony Fokker, a Dutch designer who built aircraft for the Germans, Fokker decided that the wedges were much too risky, and improved the design by connecting the trigger of an MG08 Maxim machine gun to the timing of the engine. On the evening of July 1,1915, the very first aerial engagement by a plane armed with a synchronized, forward-firing machine gun occurred just to the east of Luneville
14.
Cold War
–
The Cold War was a state of geopolitical tension after World War II between powers in the Eastern Bloc and powers in the Western Bloc. Historians do not fully agree on the dates, but a common timeframe is the period between 1947, the year the Truman Doctrine was announced, and 1991, the year the Soviet Union collapsed. The term cold is used there was no large-scale fighting directly between the two sides, although there were major regional wars, known as proxy wars, supported by the two sides. The Cold War split the temporary alliance against Nazi Germany, leaving the Soviet Union. The USSR was a Marxist–Leninist state ruled by its Communist Party and secret police, the Party controlled the press, the military, the economy and all organizations. In opposition stood the West, dominantly democratic and capitalist with a free press, a small neutral bloc arose with the Non-Aligned Movement, it sought good relations with both sides. The two superpowers never engaged directly in full-scale armed combat, but they were armed in preparation for a possible all-out nuclear world war. The first phase of the Cold War began in the first two years after the end of the Second World War in 1945, the Berlin Blockade was the first major crisis of the Cold War. With the victory of the communist side in the Chinese Civil War and the outbreak of the Korean War, the USSR and USA competed for influence in Latin America, and the decolonizing states of Africa and Asia. Meanwhile, the Hungarian Revolution of 1956 was stopped by the Soviets, the expansion and escalation sparked more crises, such as the Suez Crisis, the Berlin Crisis of 1961, and the Cuban Missile Crisis of 1962. The USSR crushed the 1968 Prague Spring liberalization program in Czechoslovakia, détente collapsed at the end of the decade with the beginning of the Soviet–Afghan War in 1979. The early 1980s were another period of elevated tension, with the Soviet downing of Korean Air Lines Flight 007, the United States increased diplomatic, military, and economic pressures on the Soviet Union, at a time when the communist state was already suffering from economic stagnation. In the mid-1980s, the new Soviet leader Mikhail Gorbachev introduced the reforms of perestroika and glasnost. Pressures for national independence grew stronger in Eastern Europe, especially Poland, Gorbachev meanwhile refused to use Soviet troops to bolster the faltering Warsaw Pact regimes as had occurred in the past. The result in 1989 was a wave of revolutions that peacefully overthrew all of the communist regimes of Central, the Communist Party of the Soviet Union itself lost control and was banned following an abortive coup attempt in August 1991. This in turn led to the dissolution of the USSR in December 1991. The United States remained as the only superpower. The Cold War and its events have left a significant legacy and it is often referred to in popular culture, especially in media featuring themes of espionage and the threat of nuclear warfare
15.
Saab 37 Viggen
–
The Saab 37 Viggen is a Swedish single-seat, single-engine, short-medium range combat aircraft. The Viggen holds the distinction of being the first canard design to be produced in quantity, several distinctive variants of the Viggen were produced to perform the roles of strike fighter, aerial reconnaissance, maritime patrol aircraft and a two-seat trainer. In the late 1970s, the all-weather fighter-interceptor aircraft JA37 variant was introduced, in November 2005, the Viggen was retired from service by the Swedish Air Force, the sole operator of the type, having been replaced by the newer Saab JAS39 Gripen. The Viggen was initially developed as a replacement for the Saab 32 Lansen in the attack role. Between 1952 and 1957, the first studies towards what would become the Viggen were carried out, over 100 different concepts were examined in these studies, involving both single- and twin engine configurations, both traditional and double delta wings, and canard wings. Even VTOL designs were considered, with separate lift engines, but were identified as being unacceptable. From the onset, the Viggen was planned as a weapon system, to be operated in conjunction with the newest revision of Swedens national electronic air defense system. It was used as the standard platform, capable of being efficiently adapted to perform all tactical mission roles. Other requirements included supersonic ability at low level, Mach 2 performance at altitude, the aircraft was also designed from the beginning to be easy to repair and service, even for personnel without much training. However, Bruzelius theory has been discredited by Simon Moores and Jerker Widén, in December 1961, the Swedish government gave its approval for the development of Aircraft System 37, which would ultimately become the Viggen. In February 1962, approval of the configuration was given and was followed by a development contract in October 1962. According to aviation authors Bill Gunston and Peter Gilchrist, the project was by far the largest industrial development task ever attempted in Sweden, during the 1960s, the Viggen accounted for 10 per cent of all Swedish R&D funding. The use of a thrust reverser enabled the sought short landing performance, during development, Saab had opted to power the type using a single large turbofan engine. In place of the Medway, Saab chose to adopt a version of the American Pratt & Whitney JT8D engine. The RM8 was heavily redesigned, using new materials to accommodate flight at Mach-2 speeds, a Swedish-built afterburner, and a fully variable nozzle. This first flight, which lasted for 43 minutes, was flown by Erik Dahlström, Saabs chief test pilot, writing at the time, aerospace publication Flight International described the flight as having been Swedens astonishing unilateral stand in the front rank of advanced aircraft-building nations. Each of the seven prototypes were assigned different roles, although the aircraft were focused on supporting the development of the initial production variant. In 1967, the Swedish Government concluded that the in-development AJ37 Viggen would be cheaper and superior to the McDonnell Douglas F-4 Phantom II
16.
Saab JAS 39 Gripen
–
The Saab JAS39 Gripen is a light single-engine multirole fighter aircraft manufactured by the Swedish aerospace company Saab. It was designed to replace the Saab 35 Draken and 37 Viggen in the Swedish Air Force, the Gripen has a delta wing and canard configuration with relaxed stability design and fly-by-wire flight controls. It is powered by the Volvo RM12, and has a top speed of Mach 2, later aircraft are modified for NATO interoperability standards and to undertake in-flight refuelling. In 1979, the Swedish government began development studies for a capable of fighter, attack. A new design from Saab was selected and developed as the JAS39, following two crashes during flight development and subsequent alterations to the aircrafts flight control software, the Gripen entered service with the Swedish Air Force in 1997. Upgraded variants, featuring more advanced avionics and adaptations for longer mission times, in order to market the aircraft to export customers, Saab has formed several partnerships and collaborative efforts with multiple overseas aerospace companies. One example of efforts was Gripen International, a joint partnership between Saab and BAE Systems formed in 2001. A further version, designated Gripen JAS 39E/F, is under development as of 2014, the changes include the adoption of a new powerplant, the General Electric F414G, an active electronically scanned array radar, and significantly increased internal fuel capacity. Saab has proposed other derivatives, including a navalised Sea Gripen for carrier operations, Sweden and Brazil have ordered the Gripen E/F and Switzerland initially selected it for procurement. As of 2013, more than 247 Gripens have been built, in the late 1970s, Sweden sought to replace its ageing Saab 35 Draken and Saab 37 Viggen. One goal was for the aircraft to be smaller than the Viggen while equalling or improving on its payload-range characteristics, several foreign designs were also studied, including the General Dynamics F-16 Fighting Falcon, the McDonnell Douglas F/A-18 Hornet, the Northrop F-20 Tigershark and the Dassault Mirage 2000. Ultimately, the Swedish government opted for a new fighter to be developed by Saab, several Saab designs were reviewed, the most promising being Project 2105, recommended to the government by the Defence Materiel Administration. The preferred aircraft was a single-engine, lightweight single-seater, embracing fly-by-wire technology, canards, the powerplant selected was the Volvo-Flygmotor RM12, a license-built derivative of the General Electric F404−400, engine development priorities were weight reduction and lowering component count. On 30 June 1982, with approval from the Riksdag, the FMV issued contracts worth SEK 25.7 billion to Saab, covering five prototypes and an initial batch of 30 production aircraft. By January 1983, a Viggen was converted to a flying test aircraft for the JAS 39s intended avionics, the JAS39 received the name Gripen via a public competition, which is the heraldry on Saabs logo. The first Gripen was rolled out on 26 April 1987, marking Saabs 50th anniversary, originally planned to fly in 1987, the first flight was delayed by 18 months due to issues with the flight control system. On 9 December 1988, the first prototype took its 51-minute maiden flight with pilot Stig Holmström at the controls, during the test programme, concern surfaced about the aircrafts avionics, specifically the fly-by-wire flight control system, and the relaxed stability design. On 2 February 1989, this led to the crash of the prototype during an attempted landing at Linköping
17.
Austria
–
Austria, officially the Republic of Austria, is a federal republic and a landlocked country of over 8.7 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Hungary and Slovakia to the east, Slovenia and Italy to the south, the territory of Austria covers 83,879 km2. The terrain is mountainous, lying within the Alps, only 32% of the country is below 500 m. The majority of the population speaks local Bavarian dialects of German as their native language, other local official languages are Hungarian, Burgenland Croatian, and Slovene. The origins of modern-day Austria date back to the time of the Habsburg dynasty, from the time of the Reformation, many northern German princes, resenting the authority of the Emperor, used Protestantism as a flag of rebellion. Following Napoleons defeat, Prussia emerged as Austrias chief competitor for rule of a greater Germany, Austrias defeat by Prussia at the Battle of Königgrätz, during the Austro-Prussian War of 1866, cleared the way for Prussia to assert control over the rest of Germany. In 1867, the empire was reformed into Austria-Hungary, Austria was thus the first to go to war in the July Crisis, which would ultimately escalate into World War I. The First Austrian Republic was established in 1919, in 1938 Nazi Germany annexed Austria in the Anschluss. This lasted until the end of World War II in 1945, after which Germany was occupied by the Allies, in 1955, the Austrian State Treaty re-established Austria as a sovereign state, ending the occupation. In the same year, the Austrian Parliament created the Declaration of Neutrality which declared that the Second Austrian Republic would become permanently neutral, today, Austria is a parliamentary representative democracy comprising nine federal states. The capital and largest city, with a population exceeding 1.7 million, is Vienna, other major urban areas of Austria include Graz, Linz, Salzburg and Innsbruck. Austria is one of the richest countries in the world, with a nominal per capita GDP of $43,724, the country has developed a high standard of living and in 2014 was ranked 21st in the world for its Human Development Index. Austria has been a member of the United Nations since 1955, joined the European Union in 1995, Austria also signed the Schengen Agreement in 1995, and adopted the euro currency in 1999. The German name for Austria, Österreich, meant eastern realm in Old High German, and is cognate with the word Ostarrîchi and this word is probably a translation of Medieval Latin Marchia orientalis into a local dialect. Austria was a prefecture of Bavaria created in 976, the word Austria is a Latinisation of the German name and was first recorded in the 12th century. Accordingly, Norig would essentially mean the same as Ostarrîchi and Österreich, the Celtic name was eventually Latinised to Noricum after the Romans conquered the area that encloses most of modern-day Austria, around 15 BC. Noricum later became a Roman province in the mid-first century AD, heers hypothesis is not accepted by linguists. Settled in ancient times, the Central European land that is now Austria was occupied in pre-Roman times by various Celtic tribes, the Celtic kingdom of Noricum was later claimed by the Roman Empire and made a province
18.
Denmark
–
The term Danish Realm refers to the relationship between Denmark proper, the Faroe Islands and Greenland—three countries constituting the Kingdom of Denmark. The legal nature of the Kingdom of Denmark is fundamentally one of a sovereign state. The Faroe Islands and Greenland have been part of the Crown of Denmark since 1397 when the Kalmar Union was ratified, legal matters in The Danish Realm are subject to the Danish Constitution. Beginning in 1953, state law issues within The Danish Realm has been governed by The Unity of the Realm, a less formal name for The Unity of the Realm is the Commonwealth of the Realm. In 1978, The Unity of The Realm was for the first time referred to as rigsfællesskabet. The name caught on and since the 1990s, both The Unity of The Realm and The Danish Realm itself has increasingly been referred to as simply rigsfællesskabet in daily parlance. The Danish Constitution stipulates that the foreign and security interests for all parts of the Danish Realm are the responsibility of the Danish government, the Faroes received home rule in 1948 and Greenland did so in 1979. In 2005, the Faroes received a self-government arrangement, and in 2009 Greenland received self rule, the Danish Realms unique state of internal affairs is acted out in the principle of The Unity of the Realm. This principle is derived from Article 1 of the Danish Constitution which specifies that constitutional law applies equally to all areas of the Danish Realm, the Constitutional Act specifies that sovereignty is to continue to be exclusively with the authorities of the Realm. The language of Denmark is Danish, and the Danish state authorities are based in Denmark, the Kingdom of Denmarks parliament, with its 179 members, is located in the capital, Copenhagen. Two of the members are elected in each of Greenland and the Faroe Islands. The Government ministries are located in Copenhagen, as is the highest court, in principle, the Danish Realm constitutes a unified sovereign state, with equal status between its constituent parts. Devolution differs from federalism in that the powers of the subnational authority ultimately reside in central government. The Self-Government Arrangements devolves political competence and responsibility from the Danish political authorities to the Faroese, the Faroese and Greenlandic authorities administer the tasks taken over from the state, enact legislation in these specific fields and have the economic responsibility for solving these tasks. The Danish government provides a grant to the Faroese and the Greenlandic authorities to cover the costs of these devolved areas. The 1948 Home Rule Act of the Faroe Islands sets out the terms of Faroese home rule, the Act states. the Faroe Islands shall constitute a self-governing community within the State of Denmark. It establishes the government of the Faroe Islands and the Faroese parliament. The Faroe Islands were previously administered as a Danish county, the Home Rule Act abolished the post of Amtmand and these powers were expanded in a 2005 Act, which named the Faroese home government as an equal partner with the Danish government
19.
Finland
–
Finland, officially the Republic of Finland, is a sovereign state in Northern Europe. A peninsula with the Gulf of Finland to the south and the Gulf of Bothnia to the west, the country has borders with Sweden to the northwest, Norway to the north. Estonia is south of the country across the Gulf of Finland, Finland is a Nordic country situated in the geographical region of Fennoscandia, which also includes Scandinavia. Finlands population is 5.5 million, and the majority of the population is concentrated in the southern region,88. 7% of the population is Finnish people who speak Finnish, a Uralic language unrelated to the Scandinavian languages, the second major group are the Finland-Swedes. In terms of area, it is the eighth largest country in Europe, Finland is a parliamentary republic with a central government based in the capital Helsinki, local governments in 311 municipalities, and an autonomous region, the Åland Islands. Over 1.4 million people live in the Greater Helsinki metropolitan area, from the late 12th century, Finland was an integral part of Sweden, a legacy reflected in the prevalence of the Swedish language and its official status. In the spirit of the notion of Adolf Ivar Arwidsson, we are not Swedes, we do not want to become Russians, let us therefore be Finns, nevertheless, in 1809, Finland was incorporated into the Russian Empire as the autonomous Grand Duchy of Finland. In 1906, Finland became the nation in the world to give the right to vote to all adult citizens. Following the 1917 Russian Revolution, Finland declared itself independent, in 1918, the fledgling state was divided by civil war, with the Bolshevik-leaning Reds supported by the equally new Soviet Russia, fighting the Whites, supported by the German Empire. After a brief attempt to establish a kingdom, the became a republic. During World War II, the Soviet Union sought repeatedly to occupy Finland, with Finland losing parts of Karelia, Salla and Kuusamo, Petsamo and some islands, Finland joined the United Nations in 1955 and established an official policy of neutrality. The Finno-Soviet Treaty of 1948 gave the Soviet Union some leverage in Finnish domestic politics during the Cold War era, Finland was a relative latecomer to industrialization, remaining a largely agrarian country until the 1950s. It rapidly developed an advanced economy while building an extensive Nordic-style welfare state, resulting in widespread prosperity, however, Finnish GDP growth has been negative in 2012–2014, with a preceding nadir of −8% in 2009. Finland is a top performer in numerous metrics of national performance, including education, economic competitiveness, civil liberties, quality of life, a large majority of Finns are members of the Evangelical Lutheran Church, though freedom of religion is guaranteed under the Finnish Constitution. The first known appearance of the name Finland is thought to be on three rune-stones. Two were found in the Swedish province of Uppland and have the inscription finlonti, the third was found in Gotland, in the Baltic Sea. It has the inscription finlandi and dates from the 13th century, the name can be assumed to be related to the tribe name Finns, which is mentioned first known time AD98. The name Suomi has uncertain origins, but a candidate for a source is the Proto-Baltic word *źemē, in addition to the close relatives of Finnish, this name is also used in the Baltic languages Latvian and Lithuanian
20.
United States
–
Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography, climate and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations. In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
21.
Bomber
–
A bomber is a combat aircraft designed to attack ground and sea targets by dropping air-to-ground weaponry, firing torpedoes or deploying air-launched cruise missiles. In 1912, during the First Balkan War, Bulgarian Air Force pilot Christo Toprakchiev suggested the use of aircraft to drop bombs on Turkish positions, captain Simeon Petrov developed the idea and created several prototypes by adapting different types of grenades and increasing their payload. This is deemed to be the first use of an aircraft as a bomber, the first heavier-than-air aircraft purposely designed for bombing were the Italian Caproni Ca 30 and British Bristol T. B.8, both of 1913. The Bristol T. B.8 was an early British single engined biplane built by the Bristol Aeroplane Company, under the command of Charles Rumney Samson, a bombing attack on German gun batteries at Middelkerke, Belgium was executed on 25 November 1914. The dirigible, or airship, was developed in the early 20th century, early airships were prone to disaster, but slowly the airship became more dependable, with a more rigid structure and stronger skin. Prior to the outbreak of war, Zeppelins, a larger and these were the first long range, strategic bombers. Although the German air arm was strong, with a total of 123 airships by the end of the war, they were vulnerable to attack and engine failure, German airships inflicted little damage on all 51 raids, with 557 Britons killed and 1,358 injured. The German Navy lost 53 of its 73 airships, and the German Army lost 26 of its 50 ships, the Caproni Ca 30 was built by Gianni Caproni in Italy. It was a biplane with three 67 kW Gnome rotary engines and first flew in October 1914. Test flights revealed power to be insufficient and the engine layout unworkable, the improved design was bought by the Italian Army and it was delivered in quantity from August 1915. Bombing raids and interdiction operations were carried out by French. Sustained attacks with a view to interrupting the enemys railway communications, in conjunction with the main operations of the Allied Armies. The most important bombers used in World War I were the French Breguet 14, British de Havilland DH-4, German Albatros C. III, the Russian Sikorsky Ilya Muromets, was the first four-engine bomber to equip a dedicated strategic bombing unit during World War I. This heavy bomber was unrivaled in the stages of the war. With engine power as a limitation, combined with the desire for accuracy and other operational factors. By the start of the war included, dive bomber — specially strengthened for vertical diving attacks for greater accuracy. Light bomber, medium bomber and heavy bomber — subjective definitions based on size, torpedo bomber — specialized aircraft armed with torpedoes. Ground attack aircraft — aircraft used against targets on a such as troop or tank concentrations
22.
Interceptor aircraft
–
An interceptor aircraft, or simply interceptor, is a type of fighter aircraft designed specifically to prevent successful missions by enemy aircraft, particularly bombers and reconnaissance aircraft. For daytime operations, conventional fighters normally fill the interceptor role, few aircraft can be considered dedicated daytime interceptors. Night fighters and bomber destroyers are, by definition, interceptors of the heavy type, examples of classic interceptors of this era include the F-106 Delta Dart, Sukhoi Su-15 and English Electric Lightning. Dedicated interceptor designs became rare, with the widely used examples designed after the 1960s being the Tornado F3, Mikoyan MiG-25 Foxbat. The first dedicated interceptor squadrons were formed up during World War I in order to defend London against attacks by Zeppelins, early units generally used aircraft withdrawn from front-line service, notably the Sopwith Pup. They were told about their targets prior to take-off from a centralized command center in the Horse Guards building. The Pup proved to have too low performance to intercept the Gotha G. IV bombers. Before Second World War started, offensive bomber speeds had improved so much that it appeared that the mission would be effectively impossible. The visual and acoustic detection had a range on the order of a few miles. This could be addressed by a cover of aircraft. The conclusion at the time was that the bomber will always get through, the introduction of radar upset this equation. Radar was able to detect aircraft at long range, on the order of 100 miles even for early systems and this provided enough time for fighters to start up, climb to altitude and chase down their targets. The introduction of jet power increased speeds from perhaps 200 miles per hour to 600 miles per hour in a single step, although radars also improved in performance, the gap between offense and defense was dramatically reduced. Large attacks could so confuse the defenses ability to communicate information to the pilots that the method of manual ground controlled interception was increasingly seen as inadequate. In the United States, this led to the introduction of the Semi-Automatic Ground Environment to computerize this task. In the 1950s, during the Cold War, an interceptor force was crucial for the great powers. Hence for a period of time they faced rapid development. Thus, the doctrine of mutually assured destruction replaced the trend of defense strengthening and their utility waned as the role became blurred into the role of the heavy air superiority fighters dominant in military thinking at the time
23.
Mach number
–
In fluid dynamics, the Mach number is a dimensionless quantity representing the ratio of flow velocity past a boundary to the local speed of sound. M = u c, where, M is the Mach number, u is the flow velocity with respect to the boundaries. By definition, Mach 1 is equal to the speed of sound, Mach 0.65 is 65% of the speed of sound, and Mach 1.35 is 35% faster than the speed of sound. The local speed of sound, and thereby the Mach number, depends on the condition of the surrounding medium, the Mach number is primarily used to determine the approximation with which a flow can be treated as an incompressible flow. The medium can be a gas or a liquid, the boundary can be the boundary of an object immersed in the medium, or of a channel such as a nozzle, diffusers or wind tunnels channeling the medium. As the Mach number is defined as the ratio of two speeds, it is a dimensionless number, if M <0. 2–0.3 and the flow is quasi-steady and isothermal, compressibility effects will be small and simplified incompressible flow equations can be used. The Mach number is named after Austrian physicist and philosopher Ernst Mach, as the Mach number is a dimensionless quantity rather than a unit of measure, with Mach, the number comes after the unit, the second Mach number is Mach 2 instead of 2 Mach. This is somewhat reminiscent of the modern ocean sounding unit mark, which was also unit-first. In the decade preceding faster-than-sound human flight, aeronautical engineers referred to the speed of sound as Machs number, never Mach 1, Mach number is useful because the fluid behaves in a similar manner at a given Mach number, regardless of other variables. As modeled in the International Standard Atmosphere, dry air at sea level, standard temperature of 15 °C. For example, the atmosphere model lapses temperature to −56.5 °C at 11,000 meters altitude. In the following table, the regimes or ranges of Mach values are referred to, generally, NASA defines high hypersonic as any Mach number from 10 to 25, and re-entry speeds as anything greater than Mach 25. Aircraft operating in this include the Space Shuttle and various space planes in development. Flight can be classified in six categories, For comparison. At transonic speeds, the field around the object includes both sub- and supersonic parts. The transonic period begins when first zones of M >1 flow appear around the object, in case of an airfoil, this typically happens above the wing. Supersonic flow can decelerate back to only in a normal shock. As the speed increases, the zone of M >1 flow increases towards both leading and trailing edges
24.
United States Air Force
–
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the seven American uniformed services. Initially part of the United States Army, the USAF was formed as a branch of the military on 18 September 1947 under the National Security Act of 1947. It is the most recent branch of the U. S. military to be formed, the U. S. Air Force is a military service organized within the Department of the Air Force, one of the three military departments of the Department of Defense. The Air Force is headed by the civilian Secretary of the Air Force, who reports to the Secretary of Defense, the U. S. Air Force provides air support for surface forces and aids in the recovery of troops in the field. As of 2015, the service more than 5,137 military aircraft,406 ICBMs and 63 military satellites. It has a $161 billion budget with 313,242 active duty personnel,141,197 civilian employees,69,200 Air Force Reserve personnel, and 105,500 Air National Guard personnel. According to the National Security Act of 1947, which created the USAF and it shall be organized, trained, and equipped primarily for prompt and sustained offensive and defensive air operations. The stated mission of the USAF today is to fly, fight, and win in air, space and we will provide compelling air, space, and cyber capabilities for use by the combatant commanders. We will excel as stewards of all Air Force resources in service to the American people, while providing precise and reliable Global Vigilance, Reach and it should be emphasized that the core functions, by themselves, are not doctrinal constructs. The purpose of Nuclear Deterrence Operations is to operate, maintain, in the event deterrence fails, the US should be able to appropriately respond with nuclear options. Dissuading others from acquiring or proliferating WMD, and the means to deliver them, moreover, different deterrence strategies are required to deter various adversaries, whether they are a nation state, or non-state/transnational actor. Nuclear strike is the ability of forces to rapidly and accurately strike targets which the enemy holds dear in a devastating manner. Should deterrence fail, the President may authorize a precise, tailored response to terminate the conflict at the lowest possible level, post-conflict, regeneration of a credible nuclear deterrent capability will deter further aggression. Finally, the Air Force regularly exercises and evaluates all aspects of operations to ensure high levels of performance. Nuclear surety ensures the safety, security and effectiveness of nuclear operations, the Air Force, in conjunction with other entities within the Departments of Defense or Energy, achieves a high standard of protection through a stringent nuclear surety program. The Air Force continues to pursue safe, secure and effective nuclear weapons consistent with operational requirements, adversaries, allies, and the American people must be highly confident of the Air Forces ability to secure nuclear weapons from accidents, theft, loss, and accidental or unauthorized use. This day-to-day commitment to precise and reliable nuclear operations is the cornerstone of the credibility of the NDO mission, positive nuclear command, control, communications, effective nuclear weapons security, and robust combat support are essential to the overall NDO function. OCA is the method of countering air and missile threats, since it attempts to defeat the enemy closer to its source
25.
Lockheed F-104 Starfighter
–
The Lockheed F-104 Starfighter is a single-engine, supersonic interceptor aircraft which later became widely used as an attack aircraft. It was originally developed by Lockheed for the United States Air Force, but became used by US Allies around the world. One of the Century Series of fighter aircraft, it was operated by the air forces of more than a dozen nations from 1958 to 2004. Its design team was led by Kelly Johnson, who went on to lead or contribute to the development of the Lockheed SR-71 Blackbird, the F-104 set numerous world records, including both airspeed and altitude records. The poor safety record of the Starfighter also brought the aircraft into the public eye, Fighter ace Erich Hartmann was forced to retire from the Luftwaffe due to his outspoken opposition to selection of the F-104. The ultimate production version of the model was the F-104S, an all-weather interceptor designed by Aeritalia for the Italian Air Force. An advanced F-104 with a wing, known as the CL-1200 Lancer, was considered. In 2018 a privately owned Starfighter is scheduled to launch a group of small cubesat satellites into low orbit by carrying the rocket aloft. Clarence Kelly Johnson, the engineer at Lockheeds Skunk Works, visited Korea in December 1951. At the time, the U. S. pilots were confronting the MiG-15 with North American F-86 Sabres, the pilots requested a small and simple aircraft with excellent performance. Armed with this information, Johnson immediately started the design of such an aircraft on his return to the United States. In March, his team was assembled, they studied several designs, ranging from small designs at 8,000 lb. The engine chosen was the new General Electric J79, an engine of dramatically improved performance in comparison with contemporary designs, the small L-246 design powered by a single J79 remained essentially identical to the L-083 Starfighter as eventually delivered. The design was presented to the Air Force in November 1952, although all were interesting, Lockheed had an insurmountable lead, and was granted a development contract in March 1953 for two prototypes, these were given the designation XF-104. Work progressed quickly, with a ready for inspection at the end of April. Meanwhile, the J79 engine was not ready, both prototypes were designed to use the Wright J65 engine, a licensed-built version of the Armstrong Siddeley Sapphire. The first prototype was completed by early 1954 and first flew on 4 March at Edwards AFB, the total time from contract to first flight was less than a year. When the USAF revealed the existence of the XF-104, they gave a vague description of it
26.
Highway
–
A highway is any public road or other public way on land. It is used for roads, but also includes other public roads and public tracks, It is not an equivalent term to controlled-access highway, or a translation for autobahn, autoroute. In North American and Australian English, major such as controlled-access highways or arterial roads are often state highways. Other roads may be designated county highways in the US and Ontario and these classifications refer to the level of government that maintains the roadway. In British English, highway is primarily a legal term, everyday use normally implies roads, while the legal use covers any route or path with a public right of access, including footpaths etc. The term has led to several related derived terms, including highway system, highway code, highway patrol, the term highway exists in distinction to waterway. Major highways are named and numbered by the governments that typically develop. Australias Highway 1 is the longest national highway in the world at over 14,500 km or 9,000 mi, China has the worlds largest network of highways followed closely by the United States of America. Some highways, like the Pan-American Highway or the European routes, some major highway routes include ferry services, such as U. S. Route 10, which crosses Lake Michigan. Traditionally highways were used by people on foot or on horses, later they also accommodated carriages, bicycles and eventually motor cars, facilitated by advancements in road construction. In the 1920s and 1930s, many nations began investing heavily in progressively more modern highway systems to spur commerce and these features are typically present on highways built as motorways. The general legal definition deals with right of use not the form of construction, the status of highway on most older roads has been gained by established public use while newer roads are typically dedicated as highways from the time they are adopted. In England and Wales, a highway is also known as The Queens Highway. The core definition of a highway is modified in various legislation for a number of purposes, scots law is similar to English law with regard to highways but with differing terminology and legislation. What is defined in England as a highway will often in Scotland be what is defined by s, Highways generally have a route number designated by the state and federal departments of transportation. Smaller roads may be termed byways, modern highway systems developed in the 20th century as the automobile gained popularity. The worlds first limited access road was constructed on Long Island New York in the United States known as the Long Island Motor Parkway or the Vanderbilt Motor Parkway, construction of the Bonn–Cologne autobahn began in 1929 and was opened in 1932 by the mayor of Cologne, Konrad Adenauer. In the USA, the Federal Aid Highway Act of 1921 enacted a fund to create a highway system
27.
Military air base
–
A military air base is an aerodrome used by a military force for the operation of military aircraft. An air base typically has some similar to a civilian airport—for example air traffic control. Some military aerodromes have passenger facilities, for example RAF Brize Norton in England has a used by passengers for the Royal Air Forces flights by TriStar to the Falkland Islands. Some air bases have revetments, hardened aircraft shelters, or even underground hangars, combat aircraft require storage of aircraft ordnance. An air base may be defended by anti-aircraft weapons and force protection troops, road air bases are highways constructed to double as auxiliary air bases in the event of war. Nations known to utilize this strategy are India, Sweden, Finland, Germany, Singapore, Switzerland, South Korea, Turkey, Poland and Pakistan. In the case of Finnish road air bases, the space needed for landing aircraft is reduced by means of an arrestor wire, similar to that used on some aircraft carriers. An aircraft carrier is a type of ship which serves as a seaborne air base. They are now a key part of the military, allowing for military aircraft to be staged much nearer the theatre of conflict, aircraft carriers were vital to the United States during World War II and to the United Kingdom in the 1982 Falklands War. They retain modern roles as well as several acres of territory an nation can move about at will. Aircraft carriers are used in disaster relief. Royal Air Force station List of Royal Canadian Air Force stations List of United States Air Force installations List of Soviet Air Force bases Naming of military air bases
28.
Conscription
–
Conscription, or drafting, is the compulsory enlistment of people in a national service, most often a military service. Conscription dates back to antiquity and continues in countries to the present day under various names. The modern system of national conscription for young men dates to the French Revolution in the 1790s. Most European nations later copied the system in peacetime, so that men at a certain age would serve 1–8 years on active duty and those conscripted may evade service, sometimes by leaving the country. As of the early 21st century, many no longer conscript soldiers. The ability to rely on such an arrangement, however, presupposes some degree of predictability with regard to both war-fighting requirements and the scope of hostilities, many states that have abolished conscription therefore still reserve the power to resume it during wartime or times of crisis. Around the reign of Hammurabi, the Babylonian Empire used a system of conscription called Ilkum, under that system those eligible were required to serve in the royal army in time of war. During times of peace they were required to provide labour for other activities of the state. In return for service, people subject to it gained the right to hold land. It is possible that this right was not to hold land per se, various forms of avoiding military service are recorded. While it was outlawed by the Code of Hammurabi, the hiring of substitutes appears to have practiced both before and after the creation of the code. Later records show that Ilkum commitments could become regularly traded, in other places, people simply left their towns to avoid their Ilkum service. Another option was to sell Ilkum lands and the commitments along with them, with the exception of a few exempted classes, this was forbidden by the Code of Hammurabi. The levies raised in this way fought as infantry under local superiors, although the exact laws varied greatly depending on the country and the period, generally these levies were only obliged to fight for one to three months. Most were subsistence farmers, and it was in everyones interest to send the men home for harvest-time, the bulk of the Anglo-Saxon English army, called the fyrd, was composed of part-time English soldiers drawn from the landowning minor nobility. These thegns were the aristocracy of the time and were required to serve with their own armour. Medieval levy in Poland was known as the pospolite ruszenie, the system of military slaves was widely used in the Middle East, beginning with the creation of the corps of Turkish slave-soldiers by the Abbasid caliph al-Mutasim in the 820s and 830s. In the middle of the 14th century, Ottoman Sultan Murad I developed personal troops to be loyal to him, the new force was built by taking Christian children from newly conquered lands, especially from the far areas of his empire, in a system known as the devşirme
29.
Afterburner
–
An afterburner is a component present on some jet engines, mostly those used on military supersonic aircraft. Its purpose is to provide an increase in thrust, usually for supersonic flight, takeoff, afterburning is achieved by injecting additional fuel into the jet pipe downstream of the turbine. Pilots can activate and deactivate afterburners in-flight, and jet engines are referred to as operating wet when afterburning is being used, an engine producing maximum thrust wet is at maximum power, while an engine producing maximum thrust dry is at military power. Jet-engine thrust is governed by the principle of mass flow rate. Thrust depends on two things, the velocity of the exhaust gas and the mass of that gas, a jet engine can produce more thrust by either accelerating the gas to a higher velocity or by having a greater mass of gas exit the engine. Designing a basic turbojet engine around the second produces the turbofan engine. Turbofans are highly efficient and can deliver high thrust for long periods. To generate increased power with a compact engine for short periods. The afterburner increases thrust primarily by accelerating the exhaust gas to a higher velocity, while the mass of the fuel added to the exhaust does contribute to an increase in exhaust mass, this effect is negligible compared to the increase in exhaust velocity. This temperature is known as the Turbine Entry Temperature, one of the engine operating parameters. After passing the turbine, the gas expands at a constant entropy. The afterburner then injects fuel downstream of the turbine and reheats the gas, in conjunction with the added heat, the pressure rises in the tailpipe and the gas is ejected through the nozzle at a higher velocity. The mass flow is slightly increased by the addition of the fuel. Afterburners do produce markedly enhanced thrust as well as a large flame at the back of the engine. This exhaust flame may show shock diamonds, which are caused by shock waves formed due to differences between ambient pressure and the exhaust pressure. These imbalances cause oscillations in the exhaust jet diameter over distance and this technique was developed to give greater thrust for take-off and supersonic performance in an aircraft similar to, but of higher weight, than the Hawker Siddeley Harrier. A jet engine afterburner is an extended exhaust section containing extra fuel injectors, since the jet engine upstream will use little of the oxygen it ingests, additional fuel can be burned after the gas flow has left the turbines. When the afterburner is turned on, fuel is injected and igniters are fired, the resulting combustion process increases the afterburner exit temperature significantly, resulting in a steep increase in engine net thrust
30.
Maiden flight
–
The maiden flight of an aircraft is the first occasion on which an aircraft leaves the ground under its own power. This is similar to a maiden voyage. The first flight of a new type is always a historic occasion for the type. In the early days of aviation it could be dangerous, because the exact handling characteristics of the aircraft were generally unknown, the first flight of a new type is almost invariably flown by a highly experienced test pilot. First flights are usually accompanied by a plane, to verify items like altitude, airspeed. A first flight is one stage in the development of an aircraft type. Unless the type is a research aircraft, the aircraft must be tested extensively to ensure that it delivers the desired performance with an acceptable margin of safety. In the case of aircraft, a new type must be certified by a governing agency before it can enter operation. An incomplete list of first flights of aircraft types, organized by date. October 23,1906 – Alberto Santos-Dumont 14-bis flight, in Bagatelle park, Paris and he flew 5,080 feet, to win the Scientific American Trophy and its $2,500 purse. July 28,1935 – Boeing B-17 Flying Fortress – World War II American heavy bomber. December 17,1935 – Douglas DC-3 – propeller-driven passenger and cargo aircraft of more than 10,000 were produced December 29,1939 – Consolidated B-24 – World War II American heavy bomber. November 2,1947 – Hughes H-4 Hercules – only flight of this oversized flying boat, July 27,1949 – de Havilland Comet – first jet airliner. August 23,1954 – Lockheed C-130 Hercules – military transport plane, may 27,1955 – Sud Aviation Caravelle – first jet airliner with engines mounted in the tail. April 25,1962 – Lockheed A-12 Blackbird – supersonic reconnaissance plane, june 29,1962 – Vickers VC10 – first airliner with 4 engines mounted in the tail. April 9,1967 – Boeing 737 – short-to-medium-range airliner, october 4,1968 – Tupolev 154 – Soviet/Russian airliner, still in operation. December 31,1968 – Tupolev Tu-144 – Soviet supersonic airliner, february 9,1969 – Boeing 747 – first widebody airliner. March 2,1969 – Anglo-French Concorde – supersonic airliner, september 19,1969 – Mil Mi-24 – Russian/Soviet-made helicopter used by many countries to this day
31.
Sound barrier
–
The sound barrier or sonic barrier is a popular term for the sudden increase in aerodynamic drag and other effects experienced by an aircraft or other object when it approaches supersonic speed. When aircraft first began to be able to close to supersonic speed. In dry air at 20 °C, the barrier is reached when an object moves at a speed of 343 metres per second. By the 1950s, new aircraft designs routinely broke the sound barrier, some common whips such as the bullwhip or stockwhip are able to move faster than sound, the tip of the whip breaks the sound barrier and causes a sharp crack—literally a sonic boom. Firearms made after the 19th century have generally had a muzzle velocity. The sound barrier may have been first breached by living beings some 150 million years ago and this finding is theoretical and disputed by others in the field. Meteorites entering the Earths atmosphere usually, if not always, descend faster than sound, the tip of the propeller on many early aircraft may reach supersonic speeds, producing a noticeable buzz that differentiates such aircraft. This is particularly noticeable on the Stearman, and noticeable on the North American T-6 Texan when it enters a sharp-breaking turn and this is undesirable, as the transonic air movement creates disruptive shock waves and turbulence. It is due to effects that propellers are known to suffer from dramatically decreased performance as they approach the speed of sound. It is easy to demonstrate that the power needed to improve performance is so great that the weight of the required engine grows faster than the output of the propeller can compensate. Nevertheless, propeller aircraft were able to approach the speed of sound in a dive, unfortunately, doing so led to numerous crashes for a variety of reasons. Most infamously, in the Mitsubishi Zero, pilots flew full power into the terrain because the rapidly increasing forces acting on the surfaces of their aircraft overpowered them. In this case, several attempts to fix it only made the problem worse and this was solved in later models with changes to the wing. in 1946. A similar problem is thought to be the cause of the 1943 crash of the BI-1 rocket aircraft in the Soviet Union. All of these effects, although unrelated in most ways, led to the concept of a barrier that makes it difficult for an aircraft to exceed the speed of sound. During WWII and immediately thereafter a number of claims were made that the barrier had been broken in a dive. The majority of these events can be dismissed as instrumentation errors. The typical airspeed indicator uses air pressure differences between two or more points on the aircraft, typically near the nose and at the side of the fuselage and this effect became known as Mach jump
32.
Fuselage
–
The fuselage is an aircrafts main body section. It holds crew, passengers, and cargo, the fuselage also serves to position control and stabilization surfaces in specific relationships to lifting surfaces, which is required for aircraft stability and maneuverability. This type of structure is still in use in lightweight aircraft using welded steel tube trusses. A box truss fuselage structure can also be out of wood—often covered with plywood. Simple box structures may be rounded by the addition of supported lightweight stringers, allowing the fabric covering to form an aerodynamic shape. Geodesic structural elements were used by Barnes Wallis for British Vickers between the wars and into World War II to form the whole of the fuselage, including its aerodynamic shape. In this type of construction multiple flat strip stringers are wound about the formers in opposite spiral directions and this proved to be light, strong, and rigid and had the advantage of being made almost entirely of wood. A similar construction using aluminum alloy was used in the Vickers Warwick with less materials than would be required for other structural types, the geodesic structure is also redundant and so can survive localized damage without catastrophic failure. A fabric covering over the completed the aerodynamic shell. The logical evolution of this is the creation of fuselages using molded plywood, in this method, the exterior surface of the fuselage is also the primary structure. A typical early form of this was built using molded plywood, a later form of this structure uses fiberglass cloth impregnated with polyester or epoxy resin, instead of plywood, as the skin. An example of a larger molded plywood aircraft is the de Havilland Mosquito fighter/light bomber of World War II, no plywood-skin fuselage is truly monocoque, since stiffening elements are incorporated into the structure to carry concentrated loads that would otherwise buckle the thin skin. The use of molded fiberglass using negative molds is prevalent in the production of many modern sailplanes. The use of molded composites for fuselage structures is being extended to large aircraft such as the Boeing 787 Dreamliner. This is the method of constructing an all-aluminum fuselage. First, a series of frames in the shape of the cross sections are held in position on a rigid fixture. These frames are then joined with lightweight longitudinal elements called stringers and these are in turn covered with a skin of sheet aluminum, attached by riveting or by bonding with special adhesives. The fixture is then disassembled and removed from the fuselage shell, which is then fitted out with wiring, controls
33.
Chord (aeronautics)
–
In aeronautics, chord refers to the imaginary straight line joining the leading and trailing edges of an aerofoil. The chord length is the distance between the edge and the point on the leading edge where the chord intersects the leading edge. The point on the edge that is used to define the chord can be defined as either the surface point of minimum radius. The wing, horizontal stabilizer, vertical stabilizer and propeller of an aircraft are all based on sections. The chord of a wing, stabilizer and propeller is determined by measuring the distance between leading and trailing edges in the direction of the airflow, the term chord is also applied to the width of wing flaps, ailerons and rudder on an aircraft. The term is applied to aerofoils in gas turbine engines such as turbojet, turboprop. Most wings are not rectangular so they have a different chord at different positions along their span, to give a characteristic figure that can be compared among various wing shapes, the mean aerodynamic chord, or MAC, is used. The MAC is somewhat complex to calculate, because most wings vary in chord over the span. This means that lift is generated on the wider inner portions. Standard mean chord is defined as wing area divided by wing span, SMC = S b, thus, the SMC is the chord of a rectangular wing with the same area and span as those of the given wing. This is a geometric figure and is rarely used in aerodynamics. Mean aerodynamic chord is defined as, MAC =2 S ∫0 b 2 c 2 d y, other terms are as for SMC. The MAC is a representation of the whole wing. The pressure distribution over the wing can be reduced to a single lift force on. Therefore, not only the length but also the position of MAC is often important. In particular, the position of center of mass of an aircraft is measured relative to the MAC. Note that the figure to the right implies that the MAC occurs at a point where leading or trailing edge sweep changes, in general, this is not the case. Any shape other than a simple trapezoid requires evaluation of the above integral, the ratio of the length of a rectangular-planform wing to its chord is known as the aspect ratio, an important indicator of the lift-induced drag the wing will create
34.
Leading edge
–
The leading edge is the part of the wing that first contacts the air, alternatively it is the foremost edge of an airfoil section. The first is a definition, the second a structural one. Associated terms are leading edge radius and leading edge stagnation point, seen in plan the leading edge may be straight or curved. A straight leading edge may be swept or unswept, the meaning that it is perpendicular to the longitudinal axis of the aircraft. As wing sweep is conventionally measured at the 25% chord line an unswept wing may have a swept or tapered leading edge, some aircraft, like the General Dynamics F-111, have swing-wings where the sweep of both wing and leading edge can be varied. In high-speed aircraft, compression heating of the air ahead of the wings can cause heating of the leading edge. Heating was a contributor to the destruction of the Space Shuttle Columbia during re-entry on February 1,2003. When sailing into the wind, the dynamics that propel a sailboat forward are the same that create lift for an airplane, the term leading edge refers to the part of the sail that first contacts the wind. A fine tapered leading edge that does not disturb the flow is desirable since 90% of the drag on a sailboat owing to sails is a result of vortex shedding from the edges of the sail, sailboats utilize a mast to support the sail
35.
Ferranti
–
Ferranti or Ferranti International plc was a UK electrical engineering and equipment firm that operated for over a century from 1885 until it went bankrupt in 1993. Known primarily for defence electronics, the company was once a constituent of the FTSE100 Index, the firm was known for work in the area of power grid systems and defence electronics. In addition, in 1951 Ferranti began selling the first commercially available computer, sebastian Ziani de Ferranti established his first business Ferranti, Thompson and Ince in 1882. The company developed the Ferranti-Thompson Alternator, Ferranti focused on alternating current power distribution early on, and was one of the few UK experts. To avoid confusion, he is referred to as Dr Ferranti to distinguish him from the Ferranti company itself. In 1885 Dr Ferranti established a new business, with Francis Ince and Charles Sparks as partners, despite being a proponent of AC Ferranti became an important supplier to many electric utility firms and power-distribution companies for both AC and DC meters. In 1887, the London Electric Supply Corporation hired Dr Ferranti for the design of their station at Deptford. He designed the building, the plant and the distribution system and on its completion in October 1890. It supplied high-voltage AC power at 10,000 volts, which was transformed to a voltage for consumer use where required. Success followed and Ferranti started producing equipment for sale. Soon the company was looking for more manufacturing space. Land prices in the London area were too high, so the moved to Hollinwood in Oldham in 1896. Over-optimistic market projections in the boom of 1896–1903, declining revenues and liquidity problems, the business was restructured in 1905, Dr Ferrantis shareholding being reduced to less than 10%. For the next years the company was run by receiver managers. He spent much of this working in partnership with the likes of J P Coats of Paisley on cotton spinning machinery. Through the early part of the power was supplied by small companies. Each plant supplied a different standard, which made the production of domestic electrical equipment inefficient. In 1910 Dr Ferranti made a speech to the IEE addressing this issue
36.
Radio
–
When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form, Radio systems need a transmitter to modulate some property of the energy produced to impress a signal on it, for example using amplitude modulation or angle modulation. Radio systems also need an antenna to convert electric currents into radio waves, an antenna can be used for both transmitting and receiving. The electrical resonance of tuned circuits in radios allow individual stations to be selected, the electromagnetic wave is intercepted by a tuned receiving antenna. Radio frequencies occupy the range from a 3 kHz to 300 GHz, a radio communication system sends signals by radio. The term radio is derived from the Latin word radius, meaning spoke of a wheel, beam of light, however, this invention would not be widely adopted. The switch to radio in place of wireless took place slowly and unevenly in the English-speaking world, the United States Navy would also play a role. Although its translation of the 1906 Berlin Convention used the terms wireless telegraph and wireless telegram, the term started to become preferred by the general public in the 1920s with the introduction of broadcasting. Radio systems used for communication have the following elements, with more than 100 years of development, each process is implemented by a wide range of methods, specialised for different communications purposes. Each system contains a transmitter, This consists of a source of electrical energy, the transmitter contains a system to modulate some property of the energy produced to impress a signal on it. This modulation might be as simple as turning the energy on and off, or altering more subtle such as amplitude, frequency, phase. Amplitude modulation of a carrier wave works by varying the strength of the signal in proportion to the information being sent. For example, changes in the strength can be used to reflect the sounds to be reproduced by a speaker. It was the used for the first audio radio transmissions. Frequency modulation varies the frequency of the carrier, the instantaneous frequency of the carrier is directly proportional to the instantaneous value of the input signal. FM has the capture effect whereby a receiver only receives the strongest signal, Digital data can be sent by shifting the carriers frequency among a set of discrete values, a technique known as frequency-shift keying. FM is commonly used at Very high frequency radio frequencies for high-fidelity broadcasts of music, analog TV sound is also broadcast using FM. Angle modulation alters the phase of the carrier wave to transmit a signal
37.
Autopilot
–
An autopilot is a system used to control the trajectory of an aircraft without constant hands-on control by a human operator being required. The autopilot system on airplanes is sometimes referred to as George. In the early days of aviation, aircraft required the attention of a pilot in order to fly safely. As aircraft range increased allowing flights of many hours, the constant attention led to serious fatigue, an autopilot is designed to perform some of the tasks of the pilot. The first aircraft autopilot was developed by Sperry Corporation in 1912, the autopilot connected a gyroscopic heading indicator and attitude indicator to hydraulically operated elevators and rudder. It permitted the aircraft to fly straight and level on a course without a pilots attention. Lawrence Sperry demonstrated it in 1914 at an aviation safety contest held in Paris, at the contest, Sperry demonstrated the credibility of the invention by flying the aircraft with his hands away from the controls and visible to onlookers of the contest. In 1930, the Royal Aircraft Establishment in the United Kingdom developed an autopilot called a pilots assister that used a gyroscope to move the flight controls. Further development of the autopilot was performed, such as improved control algorithms, also, inclusion of additional instrumentation such as the radio-navigation aids made it possible to fly during night and in bad weather. In 1947 a US Air Force C-54 made a flight, including takeoff and landing. Bill Lear developed his F-5 automatic pilot and automatic control system. In the early 1920s, the Standard Oil tanker J. A, moffet became the first ship to use an autopilot. Not all of the aircraft flying today have an autopilot system. The installation of autopilots in aircraft with more than twenty seats is generally made mandatory by international aviation regulations, there are three levels of control in autopilots for smaller aircraft. A single-axis autopilot controls an aircraft in the roll axis only, such autopilots are also known colloquially as wing levellers, a three-axis autopilot adds control in the yaw axis and is not required in many small aircraft. Autopilots in modern aircraft are three-axis and generally divide a flight into taxi, takeoff, climb, cruise, descent, approach. Autopilots exist that automate all of these phases except taxi. Landing, rollout, and taxi control to the parking position is known as CAT IIIc
38.
Landing gear
–
Landing gear is the undercarriage of an aircraft or spacecraft and may be used for either takeoff or landing. For aircraft it is generally both, for aircraft, the landing gear supports the craft when it is not flying, allowing it to take off, land, and taxi without damage. Faster aircraft usually have retractable undercarriages, which folds away during flight to reduce air resistance or drag, for launch vehicles and spacecraft landers, the landing gear is typically designed to support the vehicle only post-flight, and are typically not used for takeoff or surface movement. Aircraft landing gear usually includes wheels equipped with shock absorbers, or more advanced air/oil oleo struts, for runway. Some aircraft are equipped with skis for snow or floats for water, the undercarriage is a relatively heavy part of the vehicle, it can be as much as 7% of the takeoff weight, but more typically is 4–5%. The taildragger arrangement was common during the early era, as it allows more room for propeller clearance. Most modern aircraft have tricycle undercarriages, taildraggers are considered harder to land and take off, and usually require special pilot training. Sometimes a small wheel or skid is added to aircraft with tricycle undercarriage. Concorde, for instance, had a tail bumper wheel. Both Boeinga largest WW II bomber, the B-29 Superfortress and the 1960s-introduction Boeing 727 trijet airliner each have a tail bumper. Some aircraft with conventional landing gear have a fixed tailwheel. Another arrangement sometimes used is central main and nose gear with outriggers on the wings and this may be done where there is no convenient location on either side to attach the main undercarriage or to store it when retracted. Examples include the Lockheed U-2 spy plane and the Harrier Jump Jet, to decrease drag in flight some undercarriages retract into the wings and/or fuselage with wheels flush against the surface or concealed behind doors, this is called retractable gear. If the wheels rest protruding and partially exposed to the airstream after being retracted, most retraction systems are hydraulically operated, though some are electrically operated or even manually operated. This adds weight and complexity to the design, in retractable gear systems, the compartment where the wheels are stowed are called wheel wells, which may also diminish valuable cargo or fuel space. Pilots confirming that their landing gear is down and locked refer to three green or three in the green, a reference to the electrical indicator lights from the nosewheel/tailwheel and the two main gears. Red lights indicate the gear is in the position, amber lights indicate that the landing gear is in transit. Multiple redundancies are usually provided to prevent a failure from failing the entire landing gear extension process
39.
Flight control surfaces
–
An aircraft flight control surface is an aerodynamic device allowing a pilot to adjust and control the aircrafts flight attitude. Development of a set of flight control surfaces was a critical advance in the development of aircraft. The development of flight controls is what allowed stable flight. This article describes the control surfaces used on an aircraft of conventional design. Other fixed-wing aircraft configurations may use different control surfaces but the principles remain. The controls for rotary wing aircraft accomplish the same motions about the three axes of rotation, but manipulate the flight controls in a completely different manner. The Wright brothers are credited with developing the first practical control surfaces and it is a main part of their patent on flying. Unlike modern control surfaces, they used wing warping, in an attempt to circumvent the Wright patent, Glenn Curtiss made hinged control surfaces, the same type of concept first patented some four decades earlier in the United Kingdom. Hinged control surfaces have the advantage of not causing stresses that are a problem of wing warping and are easier to build into structures, an aircraft is free to rotate around three axes that are perpendicular to each other and intersect at its center of gravity. To control position and direction a pilot must be able to control rotation about each of them, the lateral axis, also known as transverse axis, passes through an aircraft from wingtip to wingtip. Rotation about this axis is called pitch, pitch changes the vertical direction that the aircrafts nose is pointing. The elevators are the control surfaces for pitch. The longitudinal axis passes through the aircraft from nose to tail, rotation about this axis is called roll. The angular displacement about this axis is called bank, the pilot changes bank angle by increasing the lift on one wing and decreasing it on the other. This differential lift causes rotation around the longitudinal axis, the ailerons are the primary control of bank. The rudder also has an effect on bank. The vertical axis passes through an aircraft from top to bottom, rotation about this axis is called yaw. Yaw changes the direction the aircrafts nose is pointing, left or right, the primary control of yaw is with the rudder
40.
Rudder
–
A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other conveyance that moves through a fluid medium. On an aircraft the rudder is used primarily to counter adverse yaw, a rudder operates by redirecting the fluid past the hull or fuselage, thus imparting a turning or yawing motion to the craft. In basic form, a rudder is a plane or sheet of material attached with hinges to the crafts stern, tail. Often rudders are shaped so as to minimize hydrodynamic or aerodynamic drag, on simple watercraft, a tiller—essentially, a stick or pole acting as a lever arm—may be attached to the top of the rudder to allow it to be turned by a helmsman. In larger vessels, cables, pushrods, or hydraulics may be used to link rudders to steering wheels, in typical aircraft, the rudder is operated by pedals via mechanical linkages or hydraulics. Generally, a rudder is part of the apparatus of a boat or ship that is fastened outside the hull, that is denoting all different types of oars, paddles. More specifically, the gear of ancient vessels can be classified into side-rudders and stern-mounted rudders. A third term, steering oar, can denote both types, in a Mediterranean context, side-rudders are more specifically called quarter-rudders as the later term designates more exactly the place where the rudder was mounted. Stern-mounted rudders are uniformly suspended at the back of the ship in a central position. S, a steering oar was used at this time because the rudder had not yet been invented. With a single sail, a frequent movement of the oar was required to steer a straight course. The steering oar or steering board is an oar or board to control the direction of a ship or other watercraft prior to the invention of the rudder. It is normally attached to the side in larger vessels, though in smaller ones it is rarely, if ever. Rowing oars set aside for steering appeared on large Egyptian vessels long before the time of Menes, in the Old Kingdom as much as five steering oars are found on each side of passenger boats. The tiller, at first a small pin run through the stock of the steering oar, both the tiller and the introduction of an upright steering post abaft reduced the usual number of necessary steering oars to one each side. In Iran, oars mounted on the side of ships for steering are documented from the 3rd millennium BCE in artwork, wooden models, the strength of the steering oar lay in its combination of effectiveness, adaptability and simpleness. Roman quarter steering oar mounting systems survived mostly intact through the medieval period, by the first half of the 1st century AD, steering gear mounted on the stern were also quite common in Roman river and harbour craft as proved from reliefs and archaeological finds. A tomb plaque of Hadrianic age shows a harbour tug boat in Ostia with a long stern-mounted oar for better leverage, interestingly, the boat already featured a spritsail, adding to the mobility of the harbour vessel. Further attested Roman uses of stern-mounted steering oars includes barges under tow, transport ships for wine casks, also, the well-known Zwammerdam find, a large river barge at the mouth of the Rhine, featured a large steering gear mounted on the stern
41.
Elevon
–
Elevons are aircraft control surfaces that combine the functions of the elevator and the aileron, hence the name. They are frequently used on aircraft such as flying wings. An elevon that is not part of the wing. The word elevon is a portmanteau of elevator and aileron, elevons are installed on each side of the aircraft at the trailing edge of the wing. When moved in the direction they will cause a pitching force to be applied to the airframe. When moved differentially, they cause a rolling force to be applied. These forces may be applied simultaneously by appropriate positioning of the elevons e. g. one wings elevons completely down, an aircraft with elevons is controlled as though the pilot still has separate aileron and elevator surfaces at his disposal, controlled by the yoke or stick. The inputs of the two controls are mixed either mechanically or electronically to provide the position for each elevon. They were also used on the Avro Vulcan, Northrop Grumman B-2 Spirit, Concorde and the Space Shuttle Orbiter. However, the drawback is that when the elevons move up in unison to raise the pitch of the aircraft, generating additional lift, they reduce the camber. Camber is desirable when generating high levels of lift, and so reduce the maximum lift. These may be used in unmanned aerial vehicles and 6th generation fighter aircraft. Two promising approaches are flexible wings, and fluidics, in flexible wings, much or all of a wing surface can change shape in flight to deflect air flow. The X-53 Active Aeroelastic Wing is a NASA effort, the Adaptive Compliant Wing is a military and commercial effort. In this use, fluidics promises lower mass, costs, and very low inertia and response times, aileron Flaperon Delta Wing Flying wing Spoileron Stabilator
42.
Hydraulics
–
Hydraulics is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids or fluids. At a very basic level, hydraulics is the version of pneumatics. Fluid mechanics provides the foundation for hydraulics, which focuses on the applied engineering using the properties of fluids. In fluid power, hydraulics are used for the generation, control, hydraulic topics range through some parts of science and most of engineering modules, and cover concepts such as pipe flow, dam design, fluidics and fluid control circuitry, pumps. The principles of hydraulics are in use naturally in the body within the heart. Free surface hydraulics is the branch of hydraulics dealing with surface flow, such as occurring in rivers, canals, lakes, estuaries. Its sub-field open channel flow studies the flow in open channels, the word hydraulics originates from the Greek word ὑδραυλικός which in turn originates from ὕδωρ and αὐλός. Early uses of water power date back to Mesopotamia and ancient Egypt, other early examples of water power include the Qanat system in ancient Persia and the Turpan water system in ancient Central Asia. The Greeks constructed sophisticated water and hydraulic power systems, an example is the construction by Eupalinos, under a public contract, of a watering channel for Samos, the Tunnel of Eupalinos. An early example of the usage of hydraulic wheel, probably the earliest in Europe, is the Perachora wheel, notable is the construction of the first hydraulic automata by Ctesibius and Hero of Alexandria. Hero describes a number of working machines using hydraulic power, such as the force pump, in ancient China there was Sunshu Ao, Ximen Bao, Du Shi, Zhang Heng, and Ma Jun, while medieval China had Su Song and Shen Kuo. Du Shi employed a waterwheel to power the bellows of a blast furnace producing cast iron, Zhang Heng was the first to employ hydraulics to provide motive power in rotating an armillary sphere for astronomical observation. In ancient Sri Lanka, hydraulics were used in the ancient kingdoms of Anuradhapura. The discovery of the principle of the tower, or valve pit. By the first century AD, several irrigation works had been completed. The coral on the rock at the site includes cisterns for collecting water. They were among the first to use of the siphon to carry water across valleys. They used lead widely in plumbing systems for domestic and public supply, hydraulic mining was used in the gold-fields of northern Spain, which was conquered by Augustus in 25 BC
43.
Volvo Aero
–
Volvo Aero was a Swedish aircraft, guided missiles and rocket engine manufacturer. In 2012, the company was acquired by GKN, becoming GKN Aerospace Engine Systems, nohab Flygmotorfabriker AB was founded in Trollhättan, Sweden, in 1930 to produce aircraft engines for the Swedish Board of Aviation. As the name of the company indicates it was a subsidiary to NOHAB, in 1937 it became a part of the newly founded SAAB but already in 1941 Volvo acquired a majority of the stock and the name was changed to Svenska Flygmotor AB, and later on Volvo Flygmotor. Since the 1950s the company have been the engine supplier to the Swedish Air Force. The Volvo Aero Group has 3,600 employees and in 2003 had total sales of 0.9 billion euros, today Volvo Aero is a partner in more than ten commercial engine programmes. Components from Volvo Aero are installed in more than 90% of all commercial aircraft engines sold. On 6 July 2012 Volvo Aero was acquired by the British aerospace manufacturer GKN in a SEK6.9 billion deal, in the 1950s, the Swedish Air Board constructed an unusual test facility at Flygmotor. This was an engine test facility, a form of wind tunnel and this tunnel was unique in being water-powered. A sealed underground chamber was blasted out of the granite beneath the Göta Canal, when the canal was allowed to flood the chamber, air was driven from it at high pressure and through the test chamber. A supersonic test of an engine could be carried out for around 10 minutes, use of this test facility was shared with Rolls-Royce, who used it in 1953 to develop the afterburners of the Avon RA7 engine for the Supermarine Swift F3 and Saab 32 Lansen. The Avon RA14 afterburner would also be tested here, produced as the Flygmotor RM6B for the Saab 35 Draken, Volvo Aero is a supplier of single-engine systems for military aircraft. The Saab JAS39 Gripens RM12 engine is a derivative of the General Electric F404, Svenska Flygmotor also designed the B42, horizontally-opposed four-cylinder engine, intended for the SAAB Safir. However, SAAB decided on using engines from de Havilland and Lycoming for the Safir, in the end the B42 came to power the Infanterikanonvagn 103 assault gun. A follow-up called B44 powered the Pansarbandvagn 301 armoured personnel carrier, Volvo Aero delivers engine components, mainly complex engine structures like turbine exhaust casings, turbine mid frames, LPT cases, compressor housings, LPT shafts, vanes, and large rotating parts. Volvo Aero also has a facility in Trollhättan where they did maintenance on aircraft engines, the aircraft engines are Pratt & Whitney Canada PW100 and TFE-731 engines. The Stationary gas turbines is General Electric LM1600 engine, and the DR990, Volvo Aero manufactures combustion chambers, nozzles and turbines for commercial launch vehicles. The company have produced the F-series hydraulic motors under the Volvo Flygmotor, Volvo Hydraulics, the main feature for these products is the spherical pistons with laminated segment. This technology give the possibility to obtain an angle between the shaft and the cylinder barrel
.jpg)
_Keski-Suomen_ilmailumuseo_1.JPG)
.jpg)
