1.
United States Air Force
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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
2.
Supersonic speed
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Supersonic travel is a rate of travel of an object that exceeds the speed of sound. For objects traveling in dry air of a temperature of 20 °C at sea level, speeds greater than five times the speed of sound are often referred to as hypersonic. Flights during which some parts of the air surrounding an object, such as the ends of rotor blades. This occurs typically somewhere between Mach 0.8 and Mach 1.23, sounds are traveling vibrations in the form of pressure waves in an elastic medium. In gases, sound travels longitudinally at different speeds, mostly depending on the mass and temperature of the gas. Since air temperature and composition varies significantly with altitude, Mach numbers for aircraft may change despite a constant travel speed, in water at room temperature supersonic speed can be considered as any speed greater than 1,440 m/s. In solids, sound waves can be polarized longitudinally or transversely and have higher velocities. Supersonic fracture is crack motion faster than the speed of sound in a brittle material, at the beginning of the 20th century, the term supersonic was used as an adjective to describe sound whose frequency is above the range of normal human hearing. The modern term for this meaning is ultrasonic, the tip of a bullwhip is thought to be the first man-made object to break the sound barrier, resulting in the telltale crack. The wave motion traveling through the bullwhip is what makes it capable of achieving supersonic speeds, most modern fighter aircraft are supersonic aircraft, but there have been supersonic passenger aircraft, namely Concorde and the Tupolev Tu-144. Both these passenger aircraft and some modern fighters are also capable of supercruise, since Concordes final retirement flight on November 26,2003, there are no supersonic passenger aircraft left in service. Some large bombers, such as the Tupolev Tu-160 and Rockwell B-1 Lancer are also supersonic-capable, most modern firearm bullets are supersonic, with rifle projectiles often travelling at speeds approaching and in some cases well exceeding Mach 3. Most spacecraft, most notably the Space Shuttle are supersonic at least during portions of their reentry, during ascent, launch vehicles generally avoid going supersonic below 30 km to reduce air drag. Note that the speed of sound decreases somewhat with altitude, due to lower temperatures found there, at even higher altitudes the temperature starts increasing, with the corresponding increase in the speed of sound. When an inflated balloon is burst, the pieces of latex contracts at a supersonic speed. Supersonic aerodynamics is simpler than subsonic aerodynamics because the airsheets at different points along the plane often cant affect each other, Supersonic jets and rocket vehicles require several times greater thrust to push through the extra aerodynamic drag experienced within the transonic region. Designers use the Supersonic area rule and the Whitcomb area rule to minimize changes in size. However, in applications, a supersonic aircraft will have to operate stably in both subsonic and supersonic profiles, hence aerodynamic design is more complex
3.
Strategic bomber
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In addition to strategic bombing, strategic bombers can be used for tactical missions. There are three countries including United States, Russia, and China are operating strategic bombers, the modern strategic bomber role appeared after strategic bombing was widely employed, and atomic bombs were first used in combat during World War II. An example is Frances Mirage IV, a strategic bomber replaced in service by the ASMP-equipped Mirage 2000N fighter-bomber. Study of strategic bombing continued in the interwar years and it was widely believed by the late 1930s that strategic terror bombing of cities in any war would quickly result in devastating losses and might decide a conflict in a matter of days or weeks. But theory far exceeded what most air forces could actually put into the air, Germany focused on short-range tactical bombers. Britains Royal Air Force began developing four-engine long-range bombers only in the late 1930s, the U. S. Army Air Corps was severely limited by small budgets in the late 1930s, and only barely saved the B-17 bomber that would soon be vital. The equally important B-24 first flew in 1939, both aircraft would constitute the bulk of the American bomber force that made the Allied daylight bombing of Nazi Germany possible in 1943–45. Both Britain and the U. S. were developing larger two- and four-engined designs, after American entry into the war, late, in 1941, the U. S. 8th Air Force began to develop a daylight bombing capacity using improved B-17 and B-24 four-engine aircraft. The RAF concentrated its efforts on night bombing, but neither force was able to develop adequate bombsights or tactics to allow for often-bragged pinpoint accuracy. The post-war U. S. Strategic Bombing Survey studies supported the notion of strategic bombing. Attempts to create pioneering examples of smart bombs resulted in the Azon ordnance, deployed in the European Theater, most strategic bombers of the two superpowers were designed to deliver nuclear weapons. For a time, some squadrons of Boeing B-52 Stratofortress bombers were kept in the air around the clock, the Royal Air Forces British-produced V bombers were designed and designated to be able to deliver British-made nuclear bombs to targets in European Russia. These bombers could have been able to reach and destroy cities like Kiev or Moscow before American strategic bombers, the Soviet Union produced hundreds of unlicensed, reverse-engineered copies of the American Boeing B-29 Superfortress, which the Soviet Air Forces called the Tupolev Tu-4. The Soviets later developed the jet-powered Tupolev Tu-16 Badger, the Peoples Republic of China produced a version of Tupolev Tu-16 on license from the Soviet Union in the 1960s which they named the Xian H-6, it remains in service today. Mirage IVs served until mid-1996 in the role, and to 2005 as a reconnaissance aircraft. Today the French Republic has limited its strategic armaments to a squadron of four nuclear-powered ballistic missile submarines, france also maintains an active force of supersonic fighter-bombers carrying stand-off nuclear missiles such as the ASMP, with Mach 3 speed and a range of 500 kilometers. These missiles can be delivered by the Dassault Mirage 2000N and Rafale fighter-bombers and it is likely that this bomber would also serve as a replacement for both the B-52 and B-1. The Russian Air Forces new Tu-160 strategic bombers are expected to be delivered on a regular basis over the course of 10 to 20 years, in addition, the current Tu-95 and Tu-160 bombers will be periodically updated, as was done during the 1990s with the Tu-22M bombers
4.
Convair
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Convair was an American aircraft manufacturing company which later expanded into rockets and spacecraft. It also manufactured the first Atlas rockets, including the rockets that were used for the manned flights of Project Mercury. The companys subsequent Atlas-Centaur design continued this success and derivatives of the remain in use as of 2010. In 1994 most of the divisions were sold by then-owners General Dynamics to McDonnell Douglas and Lockheed. Navy, the Royal Canadian Air Force, the British flying forces, the Catalina remained in production through May 1945, and more than 4,000 were built. What was soon to be called Convair, was created in 1943 by the merger of the Consolidated Aircraft Company and the Vultee Aircraft Company. Convair always had most of its research, design, and manufacturing operations in San Diego County of Southern California, the Convair B-36 was the largest landbased piston engined bomber in the world. The Atlas missile, the F-102 Delta Dagger and F-106 Delta Dart delta-winged interceptors, and the delta-winged B-58 Hustler supersonic intercontinental nuclear bomber were all Convair products. For a period of time in the 1960s, Convair manufactured its own line of jet airliners, the Convair 880 and Convair 990. The Convair Division produced its own designs, such as several airliners, until 1965. In the 1950s Convair shifted money and effort into its missile and rocket projects, convairs Atlas rocket was originally developed in 1957 as an ICBM for the U. S. Air Force. It was replaced in 1962 by the room-temperature liquid-fueled Titan II missile, the Atlas rocket transitioned into a civilian launch vehicle and was used for the first orbital manned U. S. space flights during Project Mercury in 1962 and 1963. The S-IVB had earlier also used as the second stage of the smaller Saturn IB rocket. In 1994, the General Dynamics Corporation split and sold the original Convair Division, the airframe/aerostructures manufacturing company and the space boosters company were sold to the McDonnell Douglas Corporation. S. In 1996, General Dynamics deactivated all of the legal entities of the Convair Division. 1923 Consolidated Aircraft Corporation formed by Major Reuben H. S, Air Force and U. S. Navy aircraft designations that begin with X are merely experimental models of aircraft made only in small numbers. Military aircraft designations that begin with Y are developmental models made in small batches, in the former designation system that the Navy and the Marine Corps used, a final letter of Y identified a Convair or a Consolidated product, such as the PBY-5 flying boat. Centaur BGM-109 Tomahawk long-range, all-weather, subsonic cruise missile, aGM-129 Advanced Cruise Missile – stealthy, nuclear, air-launched cruise missile Convair Drive at the Toronto Pearson International Airport is believed to be named for the Convair company
5.
United States dollar
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The United States dollar is the official currency of the United States and its insular territories per the United States Constitution. It is divided into 100 smaller cent units, the circulating paper money consists of Federal Reserve Notes that are denominated in United States dollars. The U. S. dollar was originally commodity money of silver as enacted by the Coinage Act of 1792 which determined the dollar to be 371 4/16 grain pure or 416 grain standard silver, the currency most used in international transactions, it is the worlds primary reserve currency. Several countries use it as their currency, and in many others it is the de facto currency. Besides the United States, it is used as the sole currency in two British Overseas Territories in the Caribbean, the British Virgin Islands and Turks and Caicos Islands. A few countries use the Federal Reserve Notes for paper money, while the country mints its own coins, or also accepts U. S. coins that can be used as payment in U. S. dollars. After Nixon shock of 1971, USD became fiat currency, Article I, Section 8 of the U. S. Constitution provides that the Congress has the power To coin money, laws implementing this power are currently codified at 31 U. S. C. Section 5112 prescribes the forms in which the United States dollars should be issued and these coins are both designated in Section 5112 as legal tender in payment of debts. The Sacagawea dollar is one example of the copper alloy dollar, the pure silver dollar is known as the American Silver Eagle. Section 5112 also provides for the minting and issuance of other coins and these other coins are more fully described in Coins of the United States dollar. The Constitution provides that a regular Statement and Account of the Receipts and that provision of the Constitution is made specific by Section 331 of Title 31 of the United States Code. The sums of money reported in the Statements are currently being expressed in U. S. dollars, the U. S. dollar may therefore be described as the unit of account of the United States. The word dollar is one of the words in the first paragraph of Section 9 of Article I of the Constitution, there, dollars is a reference to the Spanish milled dollar, a coin that had a monetary value of 8 Spanish units of currency, or reales. In 1792 the U. S. Congress passed a Coinage Act, Section 20 of the act provided, That the money of account of the United States shall be expressed in dollars, or units. And that all accounts in the offices and all proceedings in the courts of the United States shall be kept and had in conformity to this regulation. In other words, this act designated the United States dollar as the unit of currency of the United States, unlike the Spanish milled dollar the U. S. dollar is based upon a decimal system of values. Both one-dollar coins and notes are produced today, although the form is significantly more common
6.
Bomber
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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
7.
Mach number
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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
8.
Strategic Air Command
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At a lower echelon, headquarters divisions included Aircraft Engineering, Missile Concept, and Strategic Communications. In 1992, as part of an overall post-Cold War reorganization of the U. S. Planning to reorganize for a separate and independent postwar U. S. Air Force had begun by the fall of 1945, with the Simpson Board tasked to plan. the reorganization of the Army, SAC initially totaled 37,000 USAAF personnel. S. Air Force as an independent service, kenney, initial units reporting to the Strategic Air Command headquarters on 21 March 1946 included the Second Air Force, the IX Troop Carrier Command and the 73d Air Division. In addition to the bombing mission, SAC also devoted significant resources to aerial reconnaissance. An F-13 squadron, the F-13 later re-designated as the RB-29 Superfortress, was also established, SAC conducted routine aerial reconnaissance missions near the Soviet borders or near the 12-mile international waters limit, although some missions actually penetrated into Soviet airspace. The flight profiles of these missions—above 30,000 feet and in excess of 300 knots—made interception by Soviet air forces difficult until the Soviets 1948 introduction of the MiG-15 jet fighter. Project Nanook, the Cold War’s first Top Secret reconnaissance effort, used the first RB-29 missions for mapping and visual reconnaissance in the Arctic, later missions were Project LEOPARD along the Chukchi Peninsula, followed by Projects RICKRACK, STONEWORK, and COVERALLS. In 1946, the US possessed only nine atomic bombs and twenty-seven B-29s capable at any one time of delivering them, unfortunately, postwar budget and personnel cuts had had an insidious effect on SAC as its Deputy Commander, Major General Clements McMullen, implemented mandated force reductions. This continued to wear down SAC as a command and morale plummeted, as a result, by the end of 1947, only two of SACs eleven groups were combat ready. In terms of overall Air Force basing and infrastructure, SAC continued to acquire a share of USAF infrastructure. In 1947, before the USAF was established as an independent service, construction commenced on Limestone AAF, Maine, fort Dix AAF, New Jersey, Spokane AAF, Washington, and Wendover Field, Utah were also transferred to SAC between 30 April and 1 September 1947. Following establishment of the USAF as a service, SAC bases in the United States consisted of
9.
Delta wing
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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
10.
Convair F-102 Delta Dagger
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The Convair F-102 Delta Dagger was an American interceptor aircraft that was built as part of the backbone of the United States Air Forces air defenses in the late 1950s. Entering service in 1956, its purpose was to intercept invading Soviet strategic bomber fleets during the Cold War. Designed and manufactured by Convair,1,000 F-102s were built, a member of the Century Series, the F-102 was the USAFs first operational supersonic interceptor and delta-wing fighter. It used an internal weapons bay to carry guided missiles and rockets. As originally designed, it could not achieve Mach 1 supersonic flight until redesigned with area ruling, the F-102 replaced subsonic fighter types such as the Northrop F-89 Scorpion, and by the 1960s, it saw limited service in the Vietnam War in bomber escort and ground-attack roles. It was supplemented by McDonnell F-101 Voodoos and, later, by McDonnell Douglas F-4 Phantom IIs, the follow-on replacement was the Mach-2 Convair F-106 Delta Dart, which was an extensive redesign of the F-102. On 8 October 1948, the board of officers of the U. S. Four months later, on 4 February 1949, the USAF approved the recommendation, in November 1949, the Air Force decided that the new aircraft would be built around a fire-control system. The FCS was to be designed before the airframe to ensure compatibility, the airframe and FCS together were called the weapon system. In January 1950, the USAF Air Materiel Command issued request for proposals to 50 companies for the FCS, by May, the list was revised downward to 10. Following recommendations by the committee to the Saville Board, the proposals were further reduced to two competitors, Hughes Aircraft and North American Aviation. Although the Valley Committee thought it was best to award the contract to companies, Hughes was chosen by Saville and his team on 2 October 1950. Proposals for the airframe were issued on 18 June 1950, on 2 July 1954, three companies, Convair, Republic and Lockheed won the right to build a mockup. Until then, Convair had done research into delta-winged aircraft, experimenting with different designs, of the three, the best design was to win the production contract under the name Project MX-1554. In the end, Convair emerged as the victor with its design, designated XF-102, after Lockheed dropped out, the development of three different designs was too expensive and in November, only Convair was allowed to continue with its Model 8-80. To speed development, it was proposed to equip the prototypes, continued delays to the J67 and MA-1 FCS led to the decision to place an interim aircraft with the J40 and a simpler fire control system into production as the F-102A. The failure of the J40 led to the Pratt & Whitney J57 turbojet with afterburner, rated with 10,000 pounds-force of thrust being substituted for the prototypes, the F-102B would later evolve to become the F-106A, dubbed the Ultimate Interceptor. The prototype YF-102 made its first flight on 23 October 1953, at Edwards AFB, the second aircraft flew on 11 January 1954, confirming a dismal performance
11.
General Electric J79
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The General Electric J79 is an axial-flow turbojet engine built for use in a variety of fighter and bomber aircraft and a supersonic cruise missile. The J79 was produced by General Electric Aircraft Engines in the United States, market the benefits of a bypass engine over the existing Avon turbojet. In 1959 the gas generator of the J79 was developed as a stationary 10MW-class free-turbine turboshaft engine for power, power generation. Its first application was in the research hydrofoil USS Plainview, the J79 was developed in the 1950s for reliable Mach 2 performance. Had a requirement to power their next generation bomber which became the Convair B-58, the first flight of the engine was on 20 May 1955 where the engine was placed in the bomb bay of a J47-powered B-45C. The J79 was lowered from the bay and the four J47s were shut down leaving the B-45 flying on the single J79. The YF-104 was the airplane to fly with the J79 followed by a re-engined Grumman F11F Tiger in a Navy-sponsored program to gain experience with the engine before the first flight of the F4H. The J79 was used on the F-104 Starfighter, B-58 Hustler, F-4 Phantom II, A-5 Vigilante, IAI Kfir and it was produced for more than 30 years. Over 17,000 J79s were built in the United States, and under license in Belgium, Canada, Germany, Israel, Italy, and Japan. A downgraded version of the F-16 Fighting Falcon with a J79 was proposed as a low-cost fighter for export, anyone new to variable stators had to overcome the complexity of the linkages and the difficulty of sealing the pivots and airfoil root/casing clearances. Two spools needed more knowledge about bearings and sealing, GE studied both options for nearly a year before deciding, in 1952, that they should pursue variable stators for the 12,1 pressure ratio compressor. Rolls-Royce had tested a rig compressor with four stages of variable stators in 1949, connors tells us that Pratt and Whitney chose two spools for the 12,1 J57 as they knew a lot more about bearings and sealing than about variable stators. The J79 was originally known as the X-24A and was supported by a demonstrator engine, the compressor blades are made of stainless steel and are mounted on disks and spaced with corrosion-resistant steel spacers. The J79 makes a howling sound at certain throttle settings. This strange feature led to the NASA operated F-104B Starfighter, N819NA, early engines also produced noticeable quantities of smoke, especially at mid-throttle/cruise settings, a disadvantage in a combat aircraft making them easier to visually spot. Later models were redesigned to be smokeless, the turboshaft counterpart to the J79 is the General Electric LM1500, used for land and marine applications. Many J79 derived engines have found uses as gas turbine generators in remote locations. The J79 has two derivatives, CJ805-3, and the CJ805-23 fitted to the Convair CV-880 and the Convair CV-990 respectively
12.
Boeing B-47 Stratojet
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The Boeing B-47 Stratojet was an American long range, six-engine, turbojet-powered strategic bomber designed to fly at high subsonic speed and at high altitude to avoid enemy interceptor aircraft. The B-47s primary mission was to drop bombs on the Soviet Union. With its engines carried in nacelles under the wing, the B-47 was a major innovation in post-World War II combat jet design. The B-47 entered service with the United States Air Forces Strategic Air Command in 1951 and it never saw combat as a bomber, but was a mainstay of SACs bomber strength during the late 1950s and early 1960s, and remained in use as a bomber until 1965. The B-47 arose from an informal 1943 requirement for a reconnaissance bomber. In December 1944, North American Aviation, the Convair Corp, Boeing and the Glenn Martin Company submitted proposals for the new long-range jet bomber. The USAAF awarded study contracts to all four companies, requiring that North American and Convair concentrate on four-engined designs, while Boeing, the powerplant was to be General Electrics new TG-180 turbojet engine. In May 1945, the von Kármán mission of the Army Air Forces inspected the secret German aeronautics laboratory near Braunschweig, on von Kármáns team was the eminent chief of the technical staff at Boeing, George S. Schairer. He wired his home office, Stop the bomber design, analysis work by Boeing engineer Vic Ganzer suggested an optimum sweepback angle of about 35 degrees. Boeings aeronautical engineers modified their Model 432 design to include swept wings and tail, resulting in the Model 448, the Model 448 retained its four TG-180 jet engines in its forward fuselage, with two more TG-180s in the rear fuselage. The flush-mounted air intakes for the engines were inadequate, while the USAAF disliked the installation of engines within the fuselage. The Army Air Force liked this new configuration, and so Boeings team of engineers continued to refine it, with the engines being moved further inboard. As the landing gear arrangement made rotation impossible, the gear was designed so that the aircraft rested on the ground at the proper angle for takeoff. The USAAF was very pleased with the refined Model 450 design, and in April 1946, the first XB-47 was rolled out on 12 September 1947, a few days before the USAAF became a separate service, the U. S. Air Force, on 18 September 1947. The XB-47 prototype flew its first flight on 17 December 1947, with the test pilots Robert Robbins and it flew from Boeing Field in Seattle to the Moses Lake Airfield in central Washington state, in a flight that lasted just 27 minutes, with no major problems. In Feb.1949, Russ Schleeh and Joe Howell broke all coast-to-coast speed records flying from Moses Lake Air Force Base to Andrews Air Force Base and they averaged 607.8 miles per hour. During early tests of the XB-47 prototype, the canopy came off at high speed, the copilot safely landed the aircraft. This resulted in a redesign, and the hiring of pilot Tex Johnston as chief test pilot
13.
Sonic boom
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A sonic boom is the sound associated with the shock waves created by an object traveling through the air faster than the speed of sound. Sonic booms generate enormous amounts of energy, sounding much like an explosion. The crack of a bullet passing overhead or the crack of a bullwhip are examples of a sonic boom in miniature. When an aircraft passes through the air it creates a series of waves in front of it and behind it, similar to the bow. These waves travel at the speed of sound and, as the speed of the object increases, the waves are forced together, or compressed, because they cannot get out of the way of each other. Eventually they merge into a shock wave, which travels at the speed of sound, a critical speed known as Mach 1. In smooth flight, the wave starts at the nose of the aircraft. Because the different radial directions around the direction of travel are equivalent. The half-angle between direction of flight and the shock wave α is given by, sin = v sound v object, thus the faster the plane travels, the finer and more pointed the cone is. There is a rise in pressure at the nose, decreasing steadily to a pressure at the tail. This overpressure profile is known as an N-wave because of its shape and this leads to a distinctive double boom from a supersonic aircraft. When the aircraft is maneuvering, the distribution changes into different forms. Its width depends on the altitude of the aircraft, the distance from the point on the ground where the boom is heard to the aircraft depends on its altitude and the angle α. For todays supersonic aircraft in normal operating conditions, the peak overpressure varies from less than 50 to 500 Pa for an N-wave boom, the strongest sonic boom ever recorded was 7,000 Pa and it did not cause injury to the researchers who were exposed to it. The boom was produced by an F-4 flying just above the speed of sound at an altitude of 100 feet, in recent tests, the maximum boom measured during more realistic flight conditions was 1,010 Pa. There is a probability that some damage — shattered glass, for example — will result from a sonic boom, buildings in good condition should suffer no damage by pressures of 530 Pa or less. And, typically, community exposure to sonic boom is below 100 Pa, ground motion resulting from sonic boom is rare and is well below structural damage thresholds accepted by the U. S. Bureau of Mines and other agencies. The power, or volume, of the shock wave depends on the quantity of air that is being accelerated, as the aircraft increases speed the shock cone gets tighter around the craft and becomes weaker to the point that at very high speeds and altitudes no boom is heard
14.
Surface-to-air missile
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A surface-to-air missile, or ground-to-air missile, is a missile designed to be launched from the ground to destroy aircraft or other missiles. It is one type of system, in modern armed forces, missiles have replaced most other forms of dedicated antiaircraft weapons. The first serious attempts at SAM development took place during World War II, further development in the 1940s and 1950s led to the first operational systems being introduced by most major forces during the second half of the 1950s. Smaller systems, suitable for work, evolved through the 1960s and 1970s. The American Nike Ajax was the first operational guided missile SAM system, widely used modern examples include the Patriot and S-300 wide-area systems, SM-6 naval missiles, and short-range man-portable systems like the Stinger and Strela-3. The first known idea for a guided missile was in 1925. A selenium cell was mounted on the tip of each of the rockets four tail fins, when one selenium cell was no longer in the light beam, it would be steered in the opposite direction back into the beam. During World War II, efforts were started to develop surface-to-air missiles as it was considered that flak was of little use against bombers of ever-increasing performance. The lethal radius of a shell is fairly small. Against the Boeing B-17, which operated just within the range of the numerous German eighty-eights flak guns, bombers flying at higher altitudes require larger guns and shells to reach them. This greatly increases the cost of the system, and slows the rate of fire, faster aircraft fly out of range more quickly, reducing the number of rounds fired against them. Against late-war designs like the Boeing B-29 Superfortress or jet-powered designs like the Arado Ar 234, the first serious consideration of a SAM development project was a series of conversations that took place in Germany during 1941. Von Braun became convinced a better solution was a manned rocket interceptor, the directors of the Luftwaffe flak arm were not interested in manned aircraft, and the resulting disagreements between the teams delayed serious consideration of a SAM for two years. None of these saw any real development until 1943, when the first large-scale raids by the Allied air forces started. As the urgency of the problem grew, new designs were added, including Enzian and Rheintochter, in general, these designs could be split into two groups. One set of designs would be boosted to altitude in front of the bombers and these designs included the Feuerlilie, Schmetterling and Enzian. The second group were high-speed missiles, typically supersonic, that flew directly towards their targets from below, both types used radio control for guidance, either by eye, or by comparing the returns of the missile and target on a single radar screen. Development of all systems was carried out at the same time
15.
General Dynamics F-111 Aardvark
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Developed in the 1960s by General Dynamics, it first entered service in 1967 with the United States Air Force. The Royal Australian Air Force also ordered the type and began operating F-111Cs in 1973 and its design influenced later variable-sweep wing aircraft, and some of its advanced features have since become commonplace. The F-111 suffered a variety of problems during initial development, several of its intended roles, such as an aircraft carrier-based naval interceptor with the F-111B, failed to materialize. USAF F-111 variants were retired in the 1990s, with the F-111Fs in 1996, the F-111 was replaced in USAF service by the F-15E Strike Eagle for medium-range precision strike missions, while the supersonic bomber role has been assumed by the B-1B Lancer. The RAAF was the last operator of the F-111, with its aircraft serving until December 2010, the U-2 incident of May 1960, in which an American CIA U-2 spy plane was shot down over the USSR, stunned the United States government. Besides greatly damaging US-Soviet relations, the incident showed that the Soviet Union had developed a missile that could reach aircraft above 60,000 feet. The United States Air Force Strategic Air Command and the RAF Bomber Commands plans to send subsonic, high-altitude B-47, by 1960, SAC had begun moving to low-level penetration which greatly reduced radar detection distances. At the time, SAMs were ineffective against low-flying aircraft, the Air Forces Tactical Air Command was largely concerned with the fighter-bomber and deep strike/interdiction roles. TAC was in the process of receiving its latest design, the Republic F-105 Thunderchief, which was designed to deliver nuclear weapons fast and far, but required long runways. A simpler variable geometry wing configuration with the pivot points farther out from the aircrafts centerline was reported by NASA in 1958 and this led Air Force leaders to encourage its use. In June 1960, the USAF issued specification SOR183 for a long-range interdiction/strike aircraft able to penetrate Soviet air defenses at very low altitudes, the specification also called for the aircraft to operate from short, unprepared airstrips. The Navy needed an air defense fighter with a more powerful radar. Seeking a FAD fighter, the Navy started with the subsonic, straight-winged aircraft, the Missileer was designed to carry six long-range missiles and loiter for five hours, but would be defenseless after firing its missiles. The program was canceled in 1961. The Navy had tried variable geometry wings with the XF10F Jaguar and it was NASAs simplification which made the variable geometry wings practical. By 1960, increases in aircraft weights required improved high-lift devices, Variable geometry offered high speeds, and maneuverability with heavier payloads, long range, and the ability to takeoff and land in shorter distances. The U. S. Air Force and Navy were both seeking new aircraft when Robert McNamara was appointed U. S. Secretary of Defense in January 1961. On 14 February 1961, McNamara formally directed the services to study the development of an aircraft that would satisfy both requirements
16.
Wright-Patterson Air Force Base
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Wright-Patterson Air Force Base is a United States Air Force base and census-designated place just east of Dayton, Ohio, in Greene and Montgomery counties. It includes both Wright and Patterson Fields, which were originally Wilbur Wright Field and Fairfield Aviation General Supply Depot, Patterson Field is approximately 10 miles northeast of Dayton, Wright Field is approximately 5 miles northeast of Dayton. The host unit at Wright-Patterson AFB is the 88th Air Base Wing, assigned to the Air Force Life Cycle Management Center and Air Force Materiel Command. The bases origins begin with the establishment of Wilbur Wright Field on 22 May and McCook Field in November 1917, McCook was used as a testing field and for aviation experiments. Wright was used as a field, Fairfield Aviation General Supply Depot, armorers’ school. McCooks functions were transferred to Wright Field when it was closed in October 1927, Wright-Patterson AFB was established in 1948 as a merger of Patterson and Wright Fields. In 1995, negotiations to end the Bosnian War were held at the resulting in the Dayton Agreement that ended the war. The 88th Air Base Wing is commanded by Col. John M. Devillier Its Command Chief Master Sergeant is Chief Master Sergeant John M. Mazza, the base had a total of 27,406 military, civilian and contract employees in 2010. The Greene County portion of the base is a census-designated place, Wright-Patterson AFB is one of the largest, most diverse, and organizationally complex bases in the Air Force with a long history of flight tests spanning from the Wright Brothers into the Space Age. It is the headquarters of the Air Force Materiel Command, one of the commands of the Air Force. It is also the base of the 445th Airlift Wing of the Air Force Reserve Command. Wright-Patterson is also the headquarters of the Aeronautical Systems Center and the Air Force Research Laboratory, Wright-Patterson is the host of the annual United States Air Force Marathon which occurs the weekend closest to the Air Forces anniversary. The Wing reports to the Aeronautical Systems Center, a major development and their flight exhibition company and the Wright Company School of Aviation returned 1910–1916 to use the flying field. In 1918, Wilbur Wright Field agreed to let McCook Field use hangar and shop space as well as its enlisted mechanics to assemble, after World War I,347 German aircraft were brought to the United States—some were incorporated into the Army Aeronautical Museum. The training school at Wilbur Wright Field was discontinued, Wilbur Wright Field and the depot merged after World War I to form the Fairfield Air Depot. In 1924, the Committee presented the deeds to president Calvin Coolidge for the construction of a new engineering center. The entire acreage was designated Wright Field, which had such as the Headquarters, 5th Division Air Service. New facilities were built 1925–27 on the portion of Wright Field west of Huffman Dam to house all of the McCook Field functions being relocated, on 1 July 1931, the portion of Wright Field east of Huffman Dam was redesignated Patterson Field in honor of Lieutenant Frank Stuart Patterson
17.
Boeing
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The Boeing Company is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, and satellites worldwide. The company also provides leasing and product support services, Boeing stock is a component of the Dow Jones Industrial Average. The Boeing Companys corporate headquarters are located in Chicago and the company is led by President, Boeing is organized into five primary divisions, Boeing Commercial Airplanes, Boeing Defense, Space & Security, Engineering, Operations & Technology, Boeing Capital, and Boeing Shared Services Group. Boeing bought Heaths shipyard in Seattle on the Duwamish River, which became his first airplane factory. Boeing was incorporated in Seattle by William Boeing, on July 15,1916, Boeing was later incorporated in Delaware, the original Certificate of Incorporation was filed with the Secretary of State of Delaware on July 19,1934. Boeing, who studied at Yale University, worked initially in the timber industry and this knowledge proved invaluable in his subsequent design and assembly of airplanes. The company stayed in Seattle to take advantage of the supply of spruce wood. William Boeing founded his company a few months after the June 15 maiden flight of one of the two B&W seaplanes built with the assistance of George Conrad Westervelt, a U. S. Navy engineer. Boeing and Westervelt decided to build the B&W seaplane after having flown in a Curtiss aircraft, Boeing bought a Glenn Martin Flying Birdcage seaplane and was taught to fly by Glenn Martin himself. Boeing soon crashed the Birdcage and when Martin informed Boeing that replacement parts would not become available for months, Westervelt agreed to build a better airplane and soon produced the B&W Seaplane. This first Boeing airplane was assembled in a hangar located on the northeast shore of Seattles Lake Union. Many of Boeings early planes were seaplanes, on April 6,1917, the U. S. declared War on Germany and later in the year entered World War I. On May 9,1917, the became the Boeing Airplane Company. With the U. S. entering the war, Boeing knew that the U. S. Navy needed seaplanes for training, so Boeing shipped two new Model Cs to Pensacola, Florida, where the planes were flown for the Navy. The Navy liked the Model C and ordered 50 more, the company moved its operations to a larger former shipbuilding facility known as Boeing Plant 1, located on the lower Duwamish River, Washington state. Others, including Boeing, started selling other products, Boeing built dressers, counters, and furniture, along with flat-bottom boats called Sea Sleds. In 1919 the Boeing B-1, flying boat made its first flight and it accommodated one pilot and two passengers and some mail. Over the course of eight years, it made international airmail flights from Seattle to Victoria, on May 24,1920, the Boeing Model 8 made its first flight
18.
Curtiss Aeroplane and Motor Company
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Curtiss Aeroplane and Motor Company was an American aircraft manufacturer formed in 1916 by Glenn Hammond Curtiss. After significant commercial success in the teens and 20s, it merged with the Wright Aeronautical in 1929 to form Curtiss-Wright Corporation. According to Bell, it was a scientific association, not for gain but for the love of the art. In 1909, the AEA was disbanded and Curtiss formed the Herring-Curtiss Company with Augustus Moore Herring on March 20,1909, which was renamed the Curtiss Aeroplane Company in 1910. The Curtiss Aeroplane and Motor Company was created on January 13,1916 from the Curtiss Aeroplane Company of Hammondsport, New York and Curtiss Motor Company of Bath, burgess Company of Marblehead, Massachusetts, became a subsidiary in February 1916. With the onset of World War I, military orders rose sharply, the company housed an aircraft engine factory in the former Taylor Signal Company-General Railway Signal Company. An ancillary operation was begun in Toronto, Ontario that was involved in production and training, setting up the first flying school in Canada in 1915. Curtiss was instrumental in the development of U. S. Naval Aviation by providing training for pilots, the first major order was for 144 various subtypes of the Model F trainer flying boat. In 1914, Curtiss had lured B. Douglas Thomas from Sopwith to design the Model J trainer, the Curtiss Aeroplane and Motor Company worked with the United States British and Canadian allies, resulting in JN-4 trainers being built in Canada. In order to complete large military orders, JN-4 production was distributed to five other manufacturers, after the war, large numbers of JN-4s were sold as surplus, making influential as the first plane for many interwar pilots, including Amelia Earhart. The Curtiss HS-2L flying boat was used extensively in the war for anti-submarine patrols and was operated from bases in Nova Scotia, Canada, France and Portugal. The John Cyril Porte of the Royal Navy and Curtiss worked together to improve the design of the Curtiss flying boats resulting in the Curtiss F5L and the similar Felixstowe F.3. Curtiss also worked with the US Navy to develop the NC-4, which became the first aircraft to fly across the Atlantic Ocean in 1919, making several stops en route. By the end of World War I, the Curtiss Aeroplane and Motor Company would claim to be the largest aircraft manufacturer in the world, employing 18,000 in Buffalo and 3,000 in Hammondsport, New York. Curtiss produced 10,000 aircraft during that war, and more than 100 in a single week, peace brought cancellation of wartime contracts. In September 1920, the Curtiss Aeroplane and Motor Company underwent a reorganization and Glenn Curtiss cashed out his stock in the company for $32 million. He continued as a director of the company but served only as an advisor on design, clement M. Keys gained control of the company and it later became the nucleus of a large group of aviation companies. Curtiss seaplanes won the Schneider Cup in two races, those of 1923 and 1925
19.
Douglas Aircraft Company
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The Douglas Aircraft Company was an American aerospace manufacturer based in Southern California. It was founded in 1921 by Donald Wills Douglas, Sr. Douglas Aircraft Company largely operated as a division of McDonnell Douglas after the merger. MD later merged with Boeing in 1997, the Douglas Aircraft Company was founded by Donald Wills Douglas, Sr. on July 22,1921 in Santa Monica, California, following dissolution of the Davis-Douglas Company. An early claim to fame was the first circumnavigation of the world by air in Douglas airplanes in 1924. In 1923, the U. S. Army Air Service was interested in carrying out a mission to circumnavigate the Earth for the first time by aircraft, Donald Douglas proposed a modified Douglas DT to meet the Armys needs. The two-place, open cockpit DT biplane torpedo bomber had previously produced for the U. S. Navy. The DTs were taken from the lines at the companys manufacturing plants in Rock Island, Illinois and Dayton. The modified aircraft known as the Douglas World Cruiser, also was the first major project for Jack Northrop who designed the system for the series. After the prototype was delivered in November 1923, upon the completion of tests on 19 November. Due to the expedition ahead, spare parts, including 15 extra Liberty L-12 engines,14 extra sets of pontoons. These were sent to airports along the route, the last of these aircraft was delivered to the U. S. Army on 11 March 1924. After the success of the World Cruiser, the Army Air Service ordered six similar aircraft as observation aircraft. The success of the DWC established the Douglas Aircraft Company among the aircraft companies of the world. Douglas adopted a logo that showed aircraft circling a globe, replacing the original winged heart logo, the logo evolved into an aircraft, a rocket, and a globe. It was later adopted by the McDonnell Douglas Corporation, and then became the basis of the current logo of the Boeing Company after their 1997 merger, many Douglas aircraft had long service lives. Douglas Aircraft designed and built a variety of aircraft for the U. S. military, including the Navy, Army Air Forces, Marine Corps, Air Force. The company initially built torpedo bombers for the U. S. Navy, within five years, the company was building about 100 aircraft annually. Among the early employees at Douglas were Ed Heinemann, Dutch Kindelberger, and Jack Northrop, the company retained its military market and expanded into amphibian airplanes in the late 1920s, also moving its facilities to Clover Field at Santa Monica, California
20.
Lockheed Martin
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Lockheed Martin is an American global aerospace, defense, security and advanced technologies company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995 and it is headquartered in Bethesda, Maryland, in the Washington, DC, area. Lockheed Martin employs 126,000 people worldwide, Marillyn Hewson is the current President and Chief Executive Officer. Lockheed Martin is one of the largest companies in the aerospace, defense, security and it is the worlds largest defense contractor based on revenue for fiscal year 2014. In 2013, 78% of Lockheed Martins revenues came from sales, it topped the list of US federal government contractors. In 2009 US government contracts accounted for $38.4 billion, foreign government contracts $5.8 billion, Lockheed Martin operates in five business segments, Aeronautics, Information Systems & Global Solutions, Missiles and Fire Control, Rotary and Mission Systems, and Space Systems. The company also invests in healthcare systems, renewable energy systems, intelligent energy distribution, merger talks between Lockheed Corporation and Martin Marietta began in March 1994, with the companies announcing their $10 billion planned merger on August 30,1994. The deal was finalized on March 15,1995, when the two companies approved the merger. The segments of the two companies not retained by the new company formed the basis for the present L-3 Communications, Lockheed Martin also later spun off the materials company Martin Marietta Materials. Both companies contributed important products to the new portfolio, Lockheed products included the Trident missile, P-3 Orion, F-16 Fighting Falcon, F-22 Raptor, C-130 Hercules, A-4AR Fightinghawk and the DSCS-3 satellite. Martin Marietta products included Titan rockets, Sandia National Laboratories, Space Shuttle External Tank, Viking 1 and Viking 2 landers, the Transfer Orbit Stage and various satellite models. On April 22,1996, Lockheed Martin completed the acquisition of Loral Corporations defense electronics and system integration businesses for $9.1 billion, the remainder of Loral became Loral Space & Communications. Lockheed Martin abandoned plans for a $8, the development of the spacecraft cost $193.1 million. In May 2001, Lockheed Martin sold Lockheed Martin Control Systems to BAE Systems, on November 27,2000, Lockheed completed the sale of its Aerospace Electronic Systems business to BAE Systems for $1.67 billion, a deal announced in July 2000. This group encompassed Sanders Associates, Fairchild Systems, and Lockheed Martin Space Electronics & Communications. In 2001, Lockheed Martin won the contract to build the F-35 Lightning II, in 2001, Lockheed Martin settled a nine–year investigation conducted by NASAs Office of Inspector General with the assistance of the Defense Contract Audit Agency. The company paid the United States government $7.1 million based on allegations that its predecessor, Lockheed Engineering Science Corporation, submitted false lease costs claims to NASA. On August 31,2006, Lockheed Martin won a $3.9 billion contract from NASA to design and build the CEV capsule, in 2009, NASA reduced the capsule crew requirements from the initial six seats to four for transport to the International Space Station
21.
North American Aviation
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Through a series of mergers and sales, North American Aviation became part of North American Rockwell, which later became Rockwell International and is now part of Boeing. Clement Melville Keys founded North American on December 6,1928, as a company that bought and sold interests in various airlines. However, the Air Mail Act of 1934 forced the breakup of such holding companies, North American became a manufacturing company, run by James H. Dutch Kindelberger, who had been recruited from Douglas Aircraft Company. NAA did retain ownership of Eastern Air Lines until 1938, General Motors Corporation took a controlling interest in NAA and merged it with its general aviation division in 1933, but retained the name North American Aviation. Its first planes were the GA-15 observation plane and the GA-16 trainer, followed by the O-47 and BT-9, the BC-1 of 1937 was North Americans first combat aircraft, it was based on the GA-16. In 1940, like other manufacturers, North American started gearing up for war, opening factories in Columbus, Ohio, Dallas, Texas, North American ranked eleventh among United States corporations in the value of wartime production contracts. North Americans follow-on to the BT-9 was the T-6 Texan trainer, of which 17,000 were built, the twin-engine B-25 Mitchell bomber achieved fame in the Doolittle Raid and was used in all combat theaters of operation. The P-51 Mustang was initially produced for Britain as an alternative to the Curtiss P-40 Warhawk, the derivative A-36 Apache was developed as a ground attack aircraft and dive bomber. Post-war, North Americans employment dropped from a high of 91,000 to 5,000 in 1946, on V-J Day, North American had orders from the U. S. government for 8,000 aircraft. A few months later, that had dropped to 24, two years later in 1948, General Motors divested NAA as a public company. The Buckeyes name would be an acknowledgment to the tree of Ohio. The North American F-86 Sabre started out as a redesigned Fury and its successor, the North American F-100 Super Sabre, was also popular. Some 6,656 F-86s were produced in the United States, to accommodate its Sabre production, North American opened facilities in a former Curtiss-Wright plant in Columbus, Ohio. It also moved into a former Consolidated-Vultee Aircraft plant at Downey, California, by the end of 1952, North American sales topped $315 million. Employment at the Columbus plant grew from 1,600 in 1950 to 18,000 in 1952, Atomics International was a division of North American Aviation which began as the Atomic Energy Research Department at the Downey plant in 1948. In 1955, the department was renamed Atomics International and engaged principally in the development of nuclear technology. Atomics International was eventually merged with the Rocketdyne division in 1978, autonetics began in 1945 at North Americans Technical Research Laboratory, a small unit in the Los Angeles Divisions engineering department based in Downey, California. The division was involved in the development of systems for the Minuteman ballistic missile system
22.
Convair XF-92
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The Convair XF-92 was an early American delta-wing aircraft. Originally conceived as an interceptor, the design was later used purely for experimental purposes. However, it led Convair to use the delta-wing on a number of designs, including the F-102 Delta Dagger, F-106 Delta Dart, B-58 Hustler, prior to August 1945, the Vultee Division of Consolidated-Vultee looked at the possibility of a swept-wing aircraft powered by a ducted rocket. Years earlier, the company had performed designs which involved liquid-cooled radiator engines, if properly designed, fuel would be added to the heat produced by small rocket engines, creating a pseudo-ramjet. Several companies responded, among which was Consolidated-Vultee, which submitted its design on 13 October 1945 and this design featured swept wings and V-tails, as well as a powerful propulsion system. Besides the ducted rocket, four 1,200 pounds-force rockets were positioned at the exhaust nozzle, a proposal by Consolidated Vultee was accepted in May 1946, with a proposal for a ramjet-powered aircraft, with a 45° swept wing under USAAF Air Materiel Command Secret Project MX-813. However, wind tunnel testing demonstrated a number of problems with this design, the DM1 was the first in a planned series of four similar testbed aircraft, each one exploring faster speeds. The DM1 was built to test low-speed handling only, at Langley, the thick-section airfoils of the DM1 were found to generate considerable drag at transonic speeds, and a series of experiments followed to try to explore these issues. Two lines of study were considered, sharp fillets were added to the leading edge, and the vertical stabilizer was significantly shrunken in size, thinned. This left considerable room in front of the stabilizer, where a conventional cockpit was fitted, during these tests, the tendency for the wings to generate large vortices at high angles of attack was noticed, but the significance of this was not exploited until many years later. Langley passed along the delta wing information to Convair designers Adolph Burstein, the assistant chief engineer of the San Diego Division, and Ralph Shick, chief of aerodynamic research. Convairs mixed propulsion system required a large air duct to the engine, which supplied not only the jet engine with air. This left nowhere to put a traditional cockpit, in its location it would have projected deep into the duct area. To address this, the team modified the design in a similar to the Miles M.52. Power was provided by the 1,560 lbf Westinghouse J30 assisted by a battery of six 2,000 lbf liquid-fueled rockets, the design was presented to the U. S. Air Force in 1946, and was accepted for development as the XP-92. In order to gain experience with the delta wing layout, Convair suggested building a smaller prototype, the Model 7002. The design was similar to Langleys later modifications to the DM1, using the smaller vertical surface, thinner wings. The main difference was to the stretch the fuselage rearward to provide room for the engine, construction was well underway at Vultee Field in Downey, California when North American Aviation took over the Vultee plants in summer 1947
23.
Wing loading
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In aerodynamics, wing loading is the loaded mass of the aircraft divided by the area of the wing. An aircraft with a low wing loading has a wing area relative to its mass. The faster an aircraft flies, the lift is produced by each unit of wing area, so a smaller wing can carry the same weight in level flight. This increased wing load also increases takeoff and landing distances and speeds, a high wing loading also decreases maneuverability. The same constraints apply to winged biological organisms, the table, which shows wing loadings, is intended to give an idea of the range of wing loadings used by aircraft. There will be variations amongst variants of any particular type, the dates are approximate, indicating period of introduction. The upper critical limit for bird flight is about 25 kg/m2, an analysis of bird flight which looked at 138 species ranging in mass from 10 g to 10 kg, from small passerines to swans and cranes found wing loadings from about 1 to 20 kg/m2. The wing loadings of some of the lightest aircraft fall comfortably within this range, one typical hang glider has a maximum wing loading of 6.3 kg/m2, and an ultralight rigid glider 8.3 kg/m2. Wing loading is a measure of the general maneuvering performance of an aircraft. Wings generate lift owing to the motion of air over the wing surface, larger wings move more air, so an aircraft with a large wing area relative to its mass will have more lift available at any given speed. Therefore, an aircraft with wing loading will be able to take off. It will also be able to turn at a higher speed. Quantitatively, the lift force L on a wing of area A, traveling at speed v is given by L A =12 v 2 ρ C L, where ρ is the density of air and CL is the lift coefficient. The latter is a number of order unity which depends on the wing cross-sectional profile. At take-off or in flight, neither climbing nor diving, the lift force. With L/A = Mg/A =WSg, where M is the mass, WS = M/A the wing loading and g the acceleration due to gravity. As a consequence, aircraft with the same CL at takeoff under the atmospheric conditions will have takeoff speeds proportional to W S. So if a wing area is increased by 10% and nothing else changed
24.
Escape crew capsule
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An escape crew capsule allows a pilot to escape from their craft while it is subjected to extreme conditions such as high speed or altitude. The crewman remains encapsulated and protected until such time as the environment is suitable for direct exposure or the capsule reaches the ground. A cabin ejection for the XB-70 Valkyrie was also tested, the B-58s capsule had a control stick, a bottle of oxygen, and a drogue chute. The F-111 used cabin ejection where both seats were in a single 3000 lb capsule. Three of the four B-1A prototypes also used cabin ejection and they had a single capsule roughly the size of a mini-van for all four crew members. The first American attempt to design such an escape capsule was for the U. S. Navy F4D Skyray and it was tested in 1951-52 but was never installed in the aircraft. The Bell X-2, designed for flight in excess of Mach 3, could jettison the cockpit, though the pilot would still have to jump out, the first production aircraft with an escape crew capsule was the Mach 2 B-58 Hustler. It was developed by the Stanley Aviation Company for Convair, the capsule was pressurized, sheltered the pilot from the airstream, and contained food and survival supplies. During testing of the Stanley Capsule in 1962, a became the first living creature to survive a supersonic ejection. The Mach 3 XB-70s two crew escape capsules did not work well the time they were needed. On June 8,1966, XB-70 airframe AV/2 was involved in a crash with an F-104 Starfighter. Carl Crosss seat was unable to retract backwards into the escape due to high-g-forces as the plane spiraled downwards. Maj. Al Whites seat did retract but his elbow protruded from the capsule and he struggled to free his trapped elbow. As soon as he freed the doors, he was ejected from the plane, due to pain and confusion, White failed to trigger the manually activated airbag which would normally cushion the capsule upon landing. When the capsule hit the ground, White was subjected to an estimated 33 to 44 g and he received serious injuries, but nevertheless survived. In the 1960s and 1970s, the F-111 and B-1A introduced the method of jettisoning the entire front fuselage as a means of crew escape. The crew remains strapped in the cabin, unencumbered by a parachute harness, a single, large parachute brings the capsule down. On landing, an airbag system cushions the landing, in the event of a water landing the airbag acts as a flotation device
25.
Mach (speed)
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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
26.
Ejection seat
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In aircraft, an ejection seat or ejector seat is a system designed to rescue the pilot or other crew of an aircraft in an emergency. In most designs, the seat is propelled out of the aircraft by a charge or rocket motor. The concept of an escape crew capsule has also been tried. Once clear of the aircraft, the ejection seat deploys a parachute, Ejection seats are common on certain types of military aircraft. A bungee-assisted escape from an aircraft took place in 1910, in 1916 Everard Calthrop, an early inventor of parachutes, patented an ejector seat using compressed air. The modern layout for a seat was first proposed by Romanian inventor Anastase Dragomir in the late 1920s. The design, featuring a parachuted cell, was tested on 25 August 1929 at the Paris-Orly Airport near Paris and in October 1929 at Băneasa. Dragomir patented his catapult-able cockpit at the French Patent Office, the design was perfected during World War II. The first ejection seats were developed independently during World War II by Heinkel, early models were powered by compressed air and the first aircraft to be fitted with such a system was the Heinkel He 280 prototype jet-engined fighter in 1940. At 2,400 m, Schenk found he had no control, jettisoned his towline, the He 280 was never put into production status and the first operational type built anywhere, to provide ejection seats for the crew was the Heinkel He 219 Uhu night fighter in 1942. In Sweden, a version using compressed air was tested in 1941, a gunpowder ejection seat was developed by Bofors and tested in 1943 for the Saab 21. The first test in the air was on a Saab 17 on 27 February 1944, and the first real use occurred by Lt. Bengt Johansson on 29 July 1946 after a mid-air collision between a J21 and a J22. As the first operational military jet in late 1944 to ever feature one, the lightweight Heinkel He 162A Spatz featured a new type of ejection seat, in this system, the seat rode on wheels set between two pipes running up the back of the cockpit. When lowered into position, caps at the top of the seat fitted over the pipes to close them, cartridges, basically identical to shotgun shells, were placed in the bottom of the pipes, facing upward. When fired, the gases would fill the pipes, popping the caps off the end, after World War II, the need for such systems became pressing, as aircraft speeds were getting ever higher, and it was not long before the sound barrier was broken. Manual escape at such speeds would be impossible, the United States Army Air Forces experimented with downward-ejecting systems operated by a spring, but it was the work of Sir James Martin and his company Martin-Baker that was to prove crucial. The first live flight test of the Martin-Baker system took place on 24 July 1946, shortly afterward, on 17 August 1946, 1st Sgt. Larry Lambert was the first live U. S. ejectee, Lynch demonstrated the ejection seat at the Daily Express Air Pageant in 1948, ejecting from a Meteor. W.52 experimental flying wing
27.
North American XB-70 Valkyrie
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The North American Aviation XB-70 Valkyrie was the prototype version of the planned B-70 nuclear-armed, deep-penetration strategic bomber for the United States Air Force Strategic Air Command. In the late 1950s, North American Aviation designed the Valkyrie as a large, at these speeds, it was expected that the B-70 would be almost immune to interceptor aircraft, the only effective weapon against bomber aircraft at the time. The bomber would spend only a few minutes over a particular radar station, High speed also made the aircraft difficult to see on the radar displays and its high-altitude flight could not be matched by any contemporary Soviet fighter. The introduction of the first Soviet surface-to-air missiles in the late 1950s put the near-invulnerability of the B-70 in doubt, in response, the United States Air Force began flying its missions at low level, where the missile radars line of sight was limited by local terrain. In this low-level penetration role, the B-70 offered little additional performance over the B-52 it was meant to replace being far more expensive with shorter range, other alternate missions were proposed, but these were of limited scope. With the advent of intercontinental ballistic missiles during the late 1950s, the USAF eventually gave up fighting for its production and the B-70 program was canceled in 1961. Development was then turned over to a program to study the effects of long-duration high-speed flight. As such, two aircraft, designated XB-70A, were built, these aircraft were used for supersonic test-flights during 1964–69. In 1966, one crashed after colliding in mid-air with a smaller jet aircraft. At the time, nuclear weapons weighed several tons, and the need to carry fuel to fly that payload from the continental United States to the Soviet Union demanded large bombers. They also concluded that after release of bombs the aircraft would need supersonic speed to escape the critical blast-radius, the aviation industry had been studying this problem for some time. From the mid-1940s, there was much interest in using nuclear-powered aircraft in the bomber role, in a conventional jet engine, thrust is provided by heating air using jet fuel and accelerating it out a nozzle. In a nuclear engine, heat is supplied by a reactor, most designs also carried a small amount of jet fuel for use during high-power portions of flight—take-off and high-speed dashes. Zip fuels appeared to offer sufficient performance improvement to produce a bomber with supersonic speed. The new bomber was expected to service in 1963. Both nuclear and conventional designs would be considered, the nuclear-powered bomber was organized as Weapon System 125A and pursued simultaneously with the jet-powered version, Weapon System 110A. The requirement also called for a 50,000 pounds payload, the Air Force formed similar requirements for a WS-110L intercontinental reconnaissance system in 1955, but this was later canceled in 1958 due to better options. In July 1955, six contractors were selected to bid on WS-110A studies, Boeing and North American Aviation submitted proposals, and on 8 November 1955 were awarded contracts for Phase 1 development
28.
Aluminium
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Aluminium or aluminum is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic, ductile metal, Aluminium metal is so chemically reactive that native specimens are rare and limited to extreme reducing environments. Instead, it is combined in over 270 different minerals. The chief ore of aluminium is bauxite, Aluminium is remarkable for the metals low density and its ability to resist corrosion through the phenomenon of passivation. Aluminium and its alloys are vital to the industry and important in transportation and structures, such as building facades. The oxides and sulfates are the most useful compounds of aluminium, despite its prevalence in the environment, no known form of life uses aluminium salts metabolically, but aluminium is well tolerated by plants and animals. Because of these salts abundance, the potential for a role for them is of continuing interest. Aluminium is a soft, durable, lightweight, ductile. It is nonmagnetic and does not easily ignite, a fresh film of aluminium serves as a good reflector of visible light and an excellent reflector of medium and far infrared radiation. The yield strength of aluminium is 7–11 MPa, while aluminium alloys have yield strengths ranging from 200 MPa to 600 MPa. Aluminium has about one-third the density and stiffness of steel and it is easily machined, cast, drawn and extruded. Aluminium atoms are arranged in a cubic structure. Aluminium has an energy of approximately 200 mJ/m2. Aluminium is a thermal and electrical conductor, having 59% the conductivity of copper. Aluminium is capable of superconductivity, with a critical temperature of 1.2 kelvin. Aluminium is the most common material for the fabrication of superconducting qubits, the strongest aluminium alloys are less corrosion resistant due to galvanic reactions with alloyed copper. This corrosion resistance is reduced by aqueous salts, particularly in the presence of dissimilar metals. In highly acidic solutions, aluminium reacts with water to form hydrogen, primarily because it is corroded by dissolved chlorides, such as common sodium chloride, household plumbing is never made from aluminium
29.
Honeycomb structure
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The geometry of honeycomb structures can vary widely but the common feature of all such structures is an array of hollow cells formed between thin vertical walls. The cells are columnar and hexagonal in shape. A honeycomb shaped structure provides a material with minimal density and relative high out-of-plane compression properties, man-made honeycomb structural materials are commonly made by layering a honeycomb material between two thin layers that provide strength in tension. Honeycomb materials are used where flat or slightly curved surfaces are needed. They can also be found in other fields, from packaging materials in the form of paper-based honeycomb cardboard, to sporting goods like skis. Natural honeycomb structures include beehives, honeycomb weathering in rocks, tripe, man-made honeycomb structures include sandwich-structured composites with honeycomb cores. The strength of laminated or sandwich panels depends on the size of the panel, facing material used, Honeycomb composites are used widely in many industries, from aerospace industries, automotive and furniture to packaging and logistics. The material takes its name from its resemblance to a bees honeycomb – a hexagonal sheet structure. The hexagonal comb of the bee has been admired and wondered about from ancient times. The first man-made honeycomb is said to have been manufactured by Daedalus from gold by lost wax casting more than 3000 years ago, Marcus Varro reports that the Greek geometricians Euclid and Zenodorus found that the hexagon shape makes most efficient use of space and building materials. The interior ribbing and hidden chambers in the dome of the Pantheon in Rome is an example of a honeycomb structure. The first paper honeycomb structures might have made by the Chinese 2000 years ago for ornaments. Paper honeycombs and the production process has been invented in Halle/Saale in Germany by Hans Heilbrun in 1901 for decorative applications. First honeycomb structures from corrugated metal sheets had been proposed for bee keeping in 1890, for the same purpose, as foundation sheets to harvest more honey, a honeycomb moulding process using a paper paste glue mixture had been patented in 1878. The three basic techniques for production that are still used today—expansion, corrugation and moulding—were already developed by 1901 for non-sandwich applications. Hugo Junkers first explored the idea of a core within a laminate structure. He proposed and patented the first honeycomb cores for aircraft application in 1915, the problem of bonding a continuous skin to cellular cores led Junkers later to the open corrugated structure, which could be riveted or welded together. The first use of structures for structural applications had been independently proposed for building application
30.
Fiberglass
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Fiberglass is a type of fiber-reinforced plastic where the reinforcement fiber is specifically glass fiber. The glass fiber may be arranged, flattened into a sheet. The plastic matrix may be a polymer matrix – most often based on thermosetting polymers such as epoxy, polyester resin. The glass fibers are made of various types of glass depending upon the fiberglass use and these glasses all contain silica or silicate, with varying amounts of oxides of calcium, magnesium, and sometimes boron. To be used in fiberglass, glass fibers have to be made very low levels of defects. Fiberglass is a lightweight material and is used for many products. Although it is not as strong and stiff as composites based on fiber, it is less brittle. Its bulk strength and weight are also better than many metals, other common names for fiberglass are glass-reinforced plastic, glass-fiber reinforced plastic or GFK. Because glass fiber itself is referred to as fiberglass, the composite is also called fiberglass reinforced plastic. This article will adopt the convention that fiberglass refers to the glass fiber reinforced composite material. A patent for this method of producing glass wool was first applied for in 1933, Owens joined with the Corning company in 1935 and the method was adapted by Owens Corning to produce its patented fibreglas in 1936. Originally, fibreglas was a wool with fibers entrapping a great deal of gas, making it useful as an insulator. A suitable resin for combining the fibreglass with a plastic to produce a material was developed in 1936 by du Pont. The first ancestor of modern polyester resins is Cyanamids resin of 1942, peroxide curing systems were used by then. With the combination of fiberglass and resin the gas content of the material was replaced by plastic and this reduced the insulation properties to values typical of the plastic, but now for the first time the composite showed great strength and promise as a structural and building material. Confusingly, many glass fiber composites continued to be called fiberglass, ray Greene of Owens Corning is credited with producing the first composite boat in 1937, but did not proceed further at the time due to the brittle nature of the plastic used. In 1939 Russia was reported to have constructed a boat of plastic materials. The first car to have a body was a 1946 prototype of the Stout Scarab
31.
Northrop Corporation
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Northrop Corporation was a leading United States aircraft manufacturer from its formation in 1939 until its 1994 merger with Grumman to form Northrop Grumman. The company is known for its development of the wing design. Jack Northrop founded three companies using his name, the first was the Avion Corporation in 1927, which was absorbed in 1929 by the United Aircraft and Transport Corporation as a subsidiary named Northrop Aviation Corporation. However, labor difficulties led to the dissolution of the corporation by Douglas in 1937, Northrop still sought his own company, and so in 1939 he established the Northrop Corporation in nearby Hawthorne, California, a site located by co-founder Moye Stephens. The corporation ranked 100th among United States corporations in the value of World War II military production contracts, the F-5 was so successful that Northrop spent much of the 1970s and 1980s attempting to duplicate its success with similar lightweight designs. Their first attempt to improve the F-5 was the N-300, which featured more powerful engines. The P-530 also included radar and other systems considered necessary on modern aircraft, nevertheless, the YF-17 Cobra was modified with help from McDonnell Douglas to become the McDonnell Douglas F/A-18 Hornet in order to fill a similar lightweight design competition for the US Navy. Northrop intended to sell a version as the F-18L, but the basic F-18A continued to outsell it, leading to a long. This garnered little interest in the market, and the project was dropped, in 1985, Northrop bought northrop. com, the sixth. com domain created. Based on the experimentation with flying wings the company developed the B-2 Spirit stealth bomber of the 1990s
32.
Sperry Corporation
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Sperry Corporation was a major American equipment and electronics company whose existence spanned more than seven decades of the 20th century. Through a series of mergers it exists today as a part of Unisys, during World War I the company diversified into aircraft components including bomb sights and fire control systems. In their early decades, Sperry Gyroscope and related companies were concentrated on Long Island, New York, over the years, it diversified to other locations. In 1918, Lawrence Sperry split from his father to compete over aero-instruments with the Lawrence Sperry Aircraft Company, in 1924, following the death of Lawrence on December 13,1923, the two firms were brought together. The company became Sperry Corporation in 1933, the new corporation was a holding company for a number of smaller entities such as the original Sperry Gyroscope, Ford Instrument Company, Intercontinental Aviation, Inc. and others. The company made advanced aircraft navigation equipment for the market, including the Sperry Gyroscope, the company prospered during World War II as military demand skyrocketed, ranking 19th among US corporations in the value of wartime production contracts. It specialized in high technology such as analog computer–controlled bomb sights, airborne radar systems. Postwar, the company expanded its interests in electronics and computing, producing the companys first digital computer, SPEEDAC, during the 1950s, a large part of Sperry Gyroscope moved to Phoenix, Arizona and soon became the Sperry Flight Systems Company. This was to preserve parts of this company in the event of a thermonuclear conflagration. The Gyroscope division remained headquartered in New York—in its massive Lake Success, Long Island, in 1955, Sperry acquired Remington Rand and renamed itself Sperry Rand. The company remained a military contractor. From 1967 to 1973 the corporation was involved in an acrimonious antitrust lawsuit with Honeywell, the company dropped Rand from its title and reverted to Sperry Corporation. At about the time as the Rand acquisition, Sperry Gyroscope decided to open a facility that would almost exclusively produce its marine instruments. After considerable searching and evaluation, a plant was built in Charlottesville, Virginia and it was later renamed Sperry Marine. Sperry also managed the operation from 1961 to 1975, of the large Louisiana Army Ammunition Plant near Minden, Sperry bought out and continued the RCA line of electronic digital computers, architectural cousins to the IBM System/360. In 1983, Sperry sold Vickers to Libbey Owens Ford, certain internal divisions of Sperry such as Sperry New Holland and Sperry Marine were sold off after the merger. This group is now part of Lockheed Martin, Sperry in Britain started with a factory in Pimlico, London in 1913, manufacturing gyroscopic compasses for the Royal Navy. It became the Sperry Gyroscope Co Ltd in 1915, in 1923, Lawrence Sperry was killed in an air crash near Rye, Sussex
33.
Inertial navigation system
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It is used on vehicles such as ships, aircraft, submarines, guided missiles, and spacecraft. Other terms used to refer to inertial navigation systems or closely related devices include inertial guidance system, inertial instrument, inertial measurement units, older INS systems generally used an inertial platform as their mounting point to the vehicle, and the terms are sometimes considered synonymous. Inertial measurement units typically contain three orthogonal rate-gyroscopes and three accelerometers, measuring angular velocity and linear acceleration respectively. By processing signals from these devices it is possible to track the position and orientation of a device, Inertial navigation is used in a wide range of applications including the navigation of aircraft, tactical and strategic missiles, spacecraft, submarines and ships. Recent advances in the construction of systems have made it possible to manufacture small. These advances have widened the range of applications to include areas such as human. An inertial navigation system includes at least a computer and a platform or module containing accelerometers, gyroscopes, the advantage of an INS is that it requires no external references in order to determine its position, orientation, or velocity once it has been initialized. An INS can detect a change in its position, a change in its velocity. It does this by measuring the acceleration and angular velocity applied to the system. Since it requires no external reference, it is immune to jamming, Inertial navigation systems are used in many different moving objects, including vehicles—such as aircraft, submarines, spacecraft—and guided missiles. However, their cost and complexity place constraints on the environments in which they are practical for use, Gyroscopes measure the angular velocity of the sensor frame with respect to the inertial reference frame. By using the orientation of the system in the inertial reference frame as the initial condition and integrating the angular velocity. This can be thought of as the ability of a passenger in a car to feel the car turn left and right or tilt up. Based on this alone, the passenger knows what direction the car is facing but not how fast or slow it is moving. Accelerometers measure the acceleration of the moving vehicle in the sensor or body frame. Performing integration on the inertial accelerations using the correct kinematic equations yields the inertial velocities of the system, therefore, the position must be periodically corrected by input from some other type of navigation system. The inaccuracy of a good-quality navigational system is less than 0.6 nautical miles per hour in position and on the order of tenths of a degree per hour in orientation. Accordingly, inertial navigation is used to supplement other navigation systems
34.
Star tracker
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A star tracker is an optical device that measures the position of star using photocell or a camera. A star tracker may include a processor to identify stars by comparing the pattern of observed stars with the pattern of stars in the sky. Star trackers, which require high sensitivity, may become confused by sunlight reflected from the spacecraft, star trackers are also susceptible to a variety of errors in addition to a variety of optical sources of error. There are also many sources of confusion for the star identification algorithm. There are roughly 57 bright navigational stars in common use, however, for more complex missions, entire star field databases are used to determine spacecraft orientation. These types of star catalogs can have thousands of stored in memory on board the spacecraft, or else processed using tools at the ground station
35.
Lockheed SR-71 Blackbird
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The Lockheed SR-71 Blackbird was a long-range, Mach 3+ strategic reconnaissance aircraft that was operated by the United States Air Force. It was developed as a project from the Lockheed A-12 reconnaissance aircraft in the 1960s by Lockheed. American aerospace engineer Clarence Kelly Johnson was responsible for many of the innovative concepts. During aerial reconnaissance missions, the SR-71 operated at high speeds, if a surface-to-air missile launch was detected, the standard evasive action was simply to accelerate and outfly the missile. The SR-71 was designed with a reduced radar cross-section, the SR-71 served with the U. S. Air Force from 1964 to 1998. A total of 32 aircraft were built,12 were lost in accidents, the SR-71 has been given several nicknames, including Blackbird and Habu. It has held the record for the fastest air-breathing manned aircraft since 1976. Lockheeds previous reconnaissance aircraft was the relatively slow U-2, designed for the Central Intelligence Agency, in late 1957, the CIA approached the defense contractor Lockheed to build an undetectable spy plane. The project, named Archangel, was led by Kelly Johnson, head of Lockheeds Skunk Works unit in Burbank, the work on project Archangel began in the second quarter of 1958, with aim of flying higher and faster than the U-2. Out of 11 successive designs drafted in a span of 10 months, despite this, however, its shape made it vulnerable to radar detection. After a meeting with the CIA in March 1959, the design was modified to have a 90% reduction in radar cross-section, the CIA approved a US$96 million contract for Skunk Works to build a dozen spy planes, named A-12 on 11 February 1960. The 1960 downing of Francis Gary Powerss U-2 underscored its vulnerability, the A-12 first flew at Groom Lake, Nevada, on 25 April 1962. Thirteen were built, two variants were developed, including three of the YF-12 interceptor prototype, and two of the M-21 drone carrier. The aircraft was meant to be powered by the Pratt & Whitney J58 engine, but development ran over schedule, the J58s were retrofitted as they became available, and became the standard powerplant for all subsequent aircraft in the series as well as the SR-71. The A-12 flew missions over Vietnam and North Korea before its retirement in 1968, the programs cancellation was announced on 28 December 1966, due both to budget concerns and because of the forthcoming SR-71, a derivative of the A-12. During the later period of its testing, the B-70 was proposed for a reconnaissance/strike role, when it was clear that the A-12 performance potential was much greater, the Air Force ordered a variant of the A-12 in December 1962. Originally named R-12 by Lockheed, the Air Force version was longer and heavier than the A-12, with a longer fuselage to hold more fuel, Reconnaissance equipment included signals intelligence sensors, a side looking airborne radar and a photo camera. Air Force Chief of Staff General Curtis LeMay preferred the SR designation, before the July speech, LeMay lobbied to modify Johnsons speech to read SR-71 instead of RS-71
36.
Doppler radar
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A Doppler radar is a specialized radar that uses the Doppler effect to produce velocity data about objects at a distance. It does this by bouncing a signal off a desired target. This variation gives direct and highly accurate measurements of the component of a targets velocity relative to the radar. Doppler radars are used in aviation, sounding satellites, meteorology, radar guns, radiology and healthcare, most modern weather radars use the pulse-doppler technique to examine the motion of precipitation, but it is only a part of the processing of their data. So, while these radars use a specialized form of doppler radar. It is commonly heard when a vehicle sounding a siren approaches, passes and recedes from an observer, the received frequency is higher during the approach, it is identical at the instant of passing by, and it is lower during the recession. Imagine a baseball pitcher throwing one ball every second to a catcher, assuming the balls travel at a constant velocity and the pitcher is stationary, the catcher catches one ball every second. However, if the pitcher is jogging towards the catcher, the catcher catches balls more frequently because the balls are less spaced out, the inverse is true if the pitcher is moving away from the man. He catches balls less frequently because of the backward motion. If the pitcher moves at an angle, but at the same speed, from the point of view of the pitcher, the frequency remains constant. Since with electromagnetic radiation like microwaves frequency is proportional to wavelength. Thus, the difference in velocity between a source and an observer is what gives rise to the doppler effect. The formula for radar doppler shift is the same as that for reflection of light by a moving mirror, There is no need to invoke Einsteins theory of special relativity, because all observations are made in the same frame of reference. We can then write, f d ≈2 v f t c There are four ways of producing the Doppler effect, radars may be, Coherent pulsed, Pulse-Doppler radar, Continuous wave, or Frequency modulation. Doppler allows the use of narrow band receiver filters that reduce or eliminate signals from slow moving and this effectively eliminates false signals produced by trees, clouds, insects, birds, wind, and other environmental influences. Cheap hand held Doppler radar may produce erroneous measurements, CW doppler radar only provides a velocity output as the received signal from the target is compared in frequency with the original signal. Early doppler radars included CW, but these led to the development of frequency modulated continuous wave radar. With the advent of techniques, Pulse-Doppler radars became light enough for aircraft use
37.
Wind speed
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Wind speed, or wind flow velocity, is a fundamental atmospheric quantity. Wind speed is caused by air moving from high pressure to low pressure, Wind speed affects weather forecasting, aircraft and maritime operations, construction projects, growth and metabolism rate of many plant species, and countless other implications. Wind speed is now commonly measured with an anemometer but can also be classified using the older Beaufort scale which is based on observation of specifically defined wind effects. Wind speed is affected by a number of factors and situations and these include the pressure gradient, Rossby waves and jet streams, and local weather conditions. There are also links to be found between wind speed and wind direction, notably with the gradient and terrain conditions. Pressure gradient is a term to describe the difference in air pressure between two points in the atmosphere or on the surface of the Earth and it is vital to wind speed, because the greater the difference in pressure, the faster the wind flows to balance out the variation. The pressure gradient, when combined with the Coriolis effect and friction, Rossby waves are strong winds in the upper troposphere. These operate on a scale and move from West to East. The Rossby waves are themselves a different wind speed from what we experience in the lower troposphere, the wind gust was evaluated by the WMO Evaluation Panel who found that the anemometer was mechanically sound and the gust was within statistical probability and ratified the measurement in 2010. The anemometer was mounted 10 m above ground level, the pattern and scales of the gusts suggest that a mesovortex was embedded in the already strong eyewall of the cyclone. The now second highest surface wind speed ever recorded is 372 km/h at the Mount Washington Observatory,6,288 ft above sea level in the US on 12 April 1934. The anemometer, specifically designed for use on Mount Washington was later tested by the US National Weather Bureau, Wind speeds within certain atmospheric phenomena may greatly exceed these values but have never been accurately measured. Directly measuring these tornadic winds is rarely done as the violent wind would destroy the instruments, another method of estimating is to use Doppler on Wheels to sense the wind speeds remotely. The figure of 486 km/h during the 1999 Bridge Creek–Moore tornado in Oklahoma on 3 May 1999 is often quoted as the surface wind speed. However, another figure of 512 kilometres per hour has also quoted for the same tornado. Yet another number used by the Center for Severe Weather Research for that measurement is 486 ±32 km/h, however, speeds measured by Doppler radar are not considered official records. Wind speed is a factor in the design of structures. It is often the governing factor in the required strength of a structures design
38.
Radar configurations and types
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Radar configurations and types is an article about listing the different uses of radars. Radar come in a variety of configuration in the emitter, the receiver and they usually scan the area two to four times a minute. The waves are less than a meter long. Ships and planes are metal, and reflect radio waves, the radar measures the distance to the reflector by measuring the time of the roundtrip from emission of a pulse to reception, dividing this by two, and then multiplying by the speed of light. To be accepted, the pulse has to lie within a period of time called the range gate. The radar determines the direction because the radio waves behave like a search light when emitted from the reflector of the radar sets antenna. Some targeting radars have a gate that can track a target, to eliminate clutter. They use a rapidly pulsing omnidirectional radar, usually with a powerful battery that has a long storage life. The fuzes used in anti-aircraft artillery have to be designed to accept fifty thousand g. Weather radars can resemble search radars and this radar uses radio waves along with horizontal, dual, or circular polarization. The frequency selection of weather radar is a compromise between precipitation reflectivity and attenuation due to atmospheric water vapor. Some weather radars uses doppler shift to wind speeds and dual-polarization for identification of types of precipitations. Weather radar Wind profilers Millimetre cloud radar CODAR Navigational radars resemble search radar and they are common on commercial ships and long-distance commercial aircraft. Marine radars are used by ships for collision avoidance and navigation purposes, the frequency band of radar used on most ships is x-band, but s-band radar is also installed on most oceangoing ships to provide better detection of ships in rough sea and heavy rain condition. Vessel traffic services also use marine radars for tracking ARPA and provides collision avoidance or traffic regulation of ships in the survallence area, general purpose radars are increasingly being substituted for pure navigational radars. These generally use navigational radar frequencies, but modulate the pulse so the receiver can determine the type of surface of the reflector, the best general-purpose radars distinguish the rain of heavy storms, as well as land and vehicles. Some can superimpose sonar and map data from GPS position, air traffic control uses Primary and Secondary Radars. Primary radars are a radar which reflects all kind of echoes, including aircraft
39.
Radar altimeter
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The utilization of radio altimeter equipment is categorised as so-called safety-of-life service, must be protected for Interferences, and is an essential part of Navigation. See also As the name implies, radar is the principle of the system. The system transmits radio waves down to the ground and measures the time it takes them to be reflected back up to the aircraft, the altitude above the ground is calculated from the radio waves travel time and the speed of light. Radar altimeters normally work in the E band, Ka band, or, for more advanced sea-level measurement, radar altimeters also provide a reliable and accurate method of measuring height above water, when flying long sea-tracks. These are critical for use when operating to and from oil rigs, consider a radar pulse emanating from a radar beacon traveling downwards and interacting with a flat ocean surface. The following figure shows an illustration of the vertical cross-section and top-down view of the radar pulse, the radar altimeter measures the return power of the radar pulse thats reflected off the land/ocean surface. The expected return pulse can be derived from a few basic mathematical considerations, alternatively, Frequency Modulated Continuous-wave radar can be used. The greater the frequency shift the further the distance traveled and this method can achieve much better accuracy than the pulsed radar for the same outlay and radar altimeters that use frequency modulation are industry standard. As of 2010, all commercial radar altimeters use linear frequency modulation - continuous wave, as of 2010, about 25,000 aircraft in the US have at least one radio altimeter. That includes all commercial transport and all business aircraft licensed to fly for hire, the top-down view in the figure below shows the decreased footprint size of the delay-doppler signal. First, the footprint is covering less area so the radar pulse emitted by the satellite requires much less power. It covers the radar footprint using more frequent, but less power consuming radar pulses, secondly, the return waveform has a more complex signature allowing the arrival time of the pulse to be more accurately constrained. The following list notes the error associated with radar altimetry measurements. Because tidal periods can be on the order of diurnal and semidiurnal, electromagnetic Bias - There is a sea state bias where the troughs of waves tend to focus waves back to the radar, while the crests of the waves scatter waves away from the radar. Ionosphere - The ionosphere can also impose a delay on the return signal. The electron density in the ionosphere varies throughout the day, complicating the ionosphere correction, wet Troposphere - Water vapor can also cause a delay in the radar signal which can be more difficult to correct. A delay correction for the water column in the radar measurement can be accounted for using output from meteorological models, like ECMWF. In 1924, American engineer Lloyd Espenschied invented the radio altimeter, in 1938, Bell Labs put Espenschieds device in a form that was adaptable for aircraft use
40.
M61 Vulcan
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The M61 Vulcan is a hydraulically or pneumatically driven, six-barrel, air-cooled, electrically fired Gatling-style rotary cannon which fires 20 mm rounds at an extremely high rate. The M61 and its derivatives have been the principal armament of United States military fixed-wing aircraft for fifty years. The M61 was originally produced by General Electric, after several mergers and acquisitions, it is currently produced by General Dynamics. At the end of World War II, the United States Army began to consider new directions for future military aircraft guns, the higher speeds of jet-powered fighter aircraft meant that achieving an effective number of hits would be extremely difficult without a much higher volume of fire. While captured German designs showed the potential of the revolver cannon. The Army wanted something better, combining extremely high rate of fire with exceptional reliability, in 1947, the Air Force became a separate branch of the military. The new Air Force made a request for a new aircraft gun, a lesson of World War II air combat was that German, Italian and Japanese fighters could attack American aircraft from long range with their cannon main armament. American fighters with.50 cal main armament, such as the P-51 and P-47, had to be close to the enemy in order to hit, in response to this requirement, the Armament Division of General Electric resurrected an old idea, the multi-barrel Gatling gun. With multiple barrels, the rate of fire per barrel could be lower than a revolver cannon while providing a greater overall rate of fire. In 1946, the Army issued General Electric a contract for Project Vulcan, the first GE prototypes of the 0. 60-inch caliber T45 were ground-fired in 1949, it achieved 2,500 rpm, which was increased to 4,000 rpm by 1950. By the early 1950s, the USAF decided that high velocity alone might not be sufficient to ensure target destruction and these variants of the T45 were known as the T171 and T150 respectively, and were first tested in 1952. Eventually, the 20×102 mm cartridge was determined to have the balance of projectile and explosive weight. A linkless ammunition feed system was developed for the upgraded M61A1, in 1993, General Electric sold its aerospace division, including GE Armament Systems along with the design and production tooling for the M61 and GEs other rotary cannon, to Martin Marietta. After Martins merger with Lockheed, the cannon became the responsibility of Lockheed Martin Armament Systems. Lockheed Martin Armament Systems was later acquired by General Dynamics, who produce the M61. Each of the six barrels fires once in turn during each revolution of the barrel cluster. The multiple barrels provide both a high rate of fire—around 100 rounds per second—and contribute to prolonged weapon life by minimizing barrel erosion. Mean time between jams or failures is in excess of 10,000 rounds, making it a reliable weapon
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Fire-control system
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A fire-control system is a number of components working together, usually a gun data computer, a director, and radar, which is designed to assist a weapon system in hitting its target. It performs the task as a human gunner firing a weapon. The best known United States device was the Norden bombsight, simple systems, known as lead computing sights also made their appearance inside aircraft late in the war as gyro gunsights. These devices used a gyroscope to measure turn rates, and moved the gunsights aim-point to take this into account, the only manual input to the sight was the target distance, which was typically handled by dialing in the size of the targets wing span at some known range. Small radar units were added in the period to automate even this input. By the start of the Vietnam War, a new computerized bombing predictor, called the Low Altitude Bombing System, the key advantage is that the weapon can be released accurately even when the plane is maneuvering. Most bombsights until this time required that the plane maintain a constant attitude, the LABS system was originally designed to facilitate a tactic called toss bombing, to allow the aircraft to remain out of range of a weapons blast radius. The principle of calculating the point, however, was eventually integrated into the fire control computers of later bombers and strike aircraft, allowing level, dive. In addition, as the control computer became integrated with ordnance systems. By the start of World War II, aircraft altitude performance had increased so much that anti-aircraft guns had similar predictive problems, the main difference between these systems and the ones on ships was size and speed. The USN Mk 37 system made similar assumptions except that it could predict assuming a constant rate of altitude change. The Kerrison Predictor is an example of a system that was built to solve laying in real time, simply by pointing the director at the target and then aiming the gun at a pointer it directed. It was also designed to be small and light, in order to allow it to be easily moved along with the guns it served. The radar-based M-9/SCR-584 Anti-Aircraft System was used to air defense artillery since 1943. In combination with the VT proximity fuze, this system accomplished the feat of shooting down V-1 cruise missiles with less than 100 shells per plane. This system was instrumental in the defense of London and Antwerp against the V-1, although listed in Land based fire control section anti-aircraft fire control systems can also be found on naval and aircraft systems. In the United States, Coast Artillery fire control systems began to be developed at the end of the 19th Century, early systems made use of multiple observation or base end stations to find and track targets attacking American harbors. Fire control in the Coast Artillery became more and more sophisticated in terms of correcting firing data for such factors as weather conditions, provisions were also made for adjusting firing data for the observed fall of shells
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Nuclear weapon
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A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from small amounts of matter. The first test of a bomb released the same amount of energy as approximately 20,000 tons of TNT. The first thermonuclear bomb test released the same amount of energy as approximately 10 million tons of TNT, a thermonuclear weapon weighing little more than 2,400 pounds can produce an explosive force comparable to the detonation of more than 1.2 million tons of TNT. A nuclear device no larger than traditional bombs can devastate a city by blast, fire. Nuclear weapons are considered weapons of destruction, and their use. Nuclear weapons have been used twice in nuclear warfare, both times by the United States against Japan near the end of World War II, the bombings resulted in the deaths of approximately 200,000 civilians and military personnel from acute injuries sustained from the explosions. The ethics of the bombings and their role in Japans surrender remain the subject of scholarly, since the atomic bombings of Hiroshima and Nagasaki, nuclear weapons have been detonated on over two thousand occasions for the purposes of testing and demonstration. Only a few nations possess such weapons or are suspected of seeking them, israel is also believed to possess nuclear weapons, though in a policy of deliberate ambiguity, it does not acknowledge having them. Germany, Italy, Turkey, Belgium and the Netherlands are nuclear weapons sharing states, south Africa is the only country to have independently developed and then renounced and dismantled its nuclear weapons. Modernisation of weapons continues to occur, all existing nuclear weapons derive some of their explosive energy from nuclear fission reactions. Weapons whose explosive output is exclusively from fission reactions are commonly referred to as bombs or atom bombs. This has long noted as something of a misnomer, as their energy comes from the nucleus of the atom. The latter approach is considered more sophisticated than the former and only the approach can be used if the fissile material is plutonium. A major challenge in all nuclear weapon designs is to ensure that a significant fraction of the fuel is consumed before the weapon destroys itself. The amount of energy released by fission bombs can range from the equivalent of just under a ton to upwards of 500,000 tons of TNT, all fission reactions necessarily generate fission products, the radioactive remains of the atomic nuclei split by the fission reactions. Many fission products are highly radioactive or moderately radioactive. Fission products are the radioactive component of nuclear fallout
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B43 nuclear bomb
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The B43 was a United States air-dropped variable yield nuclear weapon used by a wide variety of fighter bomber and bomber aircraft. The B43 was developed from 1956 by Los Alamos National Laboratory and it entered service in April 1961. Total production was 2,000 weapons, ending in 1965, some variants were parachute-retarded and featured a ribbon parachute. The B43 was built in two variants, Mod 1 and Mod 2, each with five yield options, depending on version, the B43 was 18 inches in diameter, and length was between 12 ft 6 in and 13 ft 8 in. The various versions weighed between 2,060 lb and 2,125 lb and it could be delivered at altitudes as low as 300 ft, with fuzing options for airburst, ground burst, free fall, contact, or laydown delivery. Explosive yield varied from 70 kilotons of TNT to 1 megaton of TNT, the B43 used the Tsetse primary design for its fission stage, as did several mid- and late-1950s designs. The B43 was one of four thermonuclear gravity bombs carried by Canadian CF-104 jets while serving in Germany between June 1964 and 1972, the B43 was also supplied for delivery by Royal Air Force Canberra and Valiant aircraft assigned to NATO under the command of SACEUR. The Skyhawk was being rolled from the number 2 hangar bay to the number 2 elevator when it was lost, the pilot LTJG D. M. Webster, airframe, and the bomb were never found. No public mention was made of the incident at the time, japan then asked for details of the incident. The B43 was phased out in the 1980s, and the last B43 weapons were retired in 1991 in favor of the newer B61 and B83 weapons. B83 nuclear bomb B61 nuclear bomb List of nuclear weapons Tsetse primary Allbombs. html data page at nuclearweaponarchive. org Video showing shipboard handling procedures for the B43 bomb
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B61 nuclear bomb
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The B61 nuclear bomb is one of the primary thermonuclear weapons in the U. S. Enduring Stockpile following the end of the Cold War and it is an intermediate-yield strategic and tactical nuclear weapon featuring a two-stage radiation implosion design. The B61 is a variable yield bomb designed for carriage by high-speed aircraft and it has a streamlined casing capable of withstanding supersonic flight speeds. The weapon is 11 ft 8 in long, with a diameter of about 13 inches, basic weight is about 700 pounds, although the weights of individual weapons may vary depending on version and fuze/retardation configuration. The B61, known before 1968 as the TX-61, was designed in 1963 and it was designed and built by the Los Alamos National Laboratory in New Mexico. It began from a program for a lightweight, streamlined weapon launched in 1961, production engineering began in 1965, with full production beginning in 1968 following a series of development problems. Total production of all versions was approximately 3,155, of which approximately 1,925 remain in service as of 2002, the warhead has changed little over the years, although early versions have been upgraded to improve the safety features. As of late 2013, there were 200 B61 bombs actively in use by the United States, of these,180 were deployed with NATO allies in Europe. Nine versions of the B61 have been produced, each shares the same physics package, with different yield options. The newest variant is the B61 Mod 11, deployed in 1997, which is a ground-penetrating bunker buster. The B61 unguided bomb should not be confused with the MGM-1 Matador cruise missile, when the B61 was still classified, aircrew were not allowed to use the term B61. Instead, it was referred to as a shape, silver bullet, the B61 has been deployed by a variety of U. S. military aircraft. USAFE and all NATO dual role aircraft can carry B61s, the Lockheed S-3 Viking was also able to deploy the B61 as a nuclear depth bomb. The B61 can fit inside the F-22 Raptors weapons bays and will also be carried by the Lockheed Martin F-35 Lightning II, as of 2005, they were deployed in Europe under the NATO nuclear sharing arrangement. NATO has agreed to improve the capabilities of this force with the increased accuracy of the B61 Mod 12 upgrade. This will, for the first time, add a modest standoff capability to the B61, as of 2013, the Pentagon was asking for an $11 billion life-extension program for the B61 bomb, which would be the most ambitious and expensive nuclear warhead refurbishment in history. Congress is opposed to this effort for cost and timeline issues, sequestration budget cuts in early 2013 have delayed any start until 2020. The Senate Energy and Water Appropriations Subcommittee stated that extending the life of B61s and consolidating its variants may not be a cheap and low-risk method to meet military requirements. The B61 Mod 12 is to replace the previous Mod 3,4,7, refurbishing the existing variants and eliminating the guidance kit would save $2–3 billion
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Reconnaissance
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In military operations, reconnaissance is the exploration outside an area occupied by friendly forces to gain information about natural features and enemy presence. Examples of reconnaissance include patrolling by troops, ships or submarines, manned/unmanned reconnaissance aircraft, satellites, espionage normally is not reconnaissance, because reconnaissance is a militarys special forces operating ahead of its main forces, spies are non-combatants operating behind enemy lines. Often called recce or recon, the verb is reconnaître. Traditionally, reconnaissance was a role that was adopted by the cavalry, speed was key in these maneuvers, thus infantry was ill suited to the task. From horses to vehicles, for warriors throughout history, commanders procured their ability to have speed and mobility, to mount and dismount, skirmishing is a traditional skill of reconnaissance, as well as harassment of the enemy. Reconnaissance conducted by ground forces includes special reconnaissance, armored reconnaissance, amphibious reconnaissance, aerial reconnaissance is reconnaissance carried out by aircraft. The purpose is to weather conditions, map terrain, and may include military purposes such as observing tangible structures, particular areas. Naval forces use aerial and satellite reconnaissance to observe enemy forces, navies also undertake hydrographic surveys and intelligence gathering. Reconnaissance satellites provide military commanders with photographs of enemy forces and other intelligence, military forces also use geographical and meteorological information from Earth observation satellites. A tracker needs to pay attention to both the environment and the psychology of his enemy. Knowledge of human psychology, sociology, and cultural backgrounds is necessary to know the actions of the enemy and this is almost as necessary as to know the physical character of the country, its climate and products. Certain people will do certain things almost without fail, certain other things, perfectly feasible, they will not do. There is no danger of knowing too much of the habits of an enemy. One should neither underestimate the enemy nor credit him with superhuman powers, fear and courage are latent in every human being, though roused into activity by very diverse means. Types of reconnaissance, Terrain-oriented reconnaissance is a survey of the terrain, force-oriented reconnaissance focuses on the enemy forces and may include target acquisition. Civil-oriented reconnaissance focuses on the dimension of the battlespace. The techniques and objectives are not mutually exclusive, it is up to the commander whether they are carried out separately or by the same unit, some military elements tasked with reconnaissance are armed only for self-defense, and rely on stealth to gather information. Others are well-enough armed to also deny information to the enemy by destroying their reconnaissance elements, reconnaissance-in-force is a type of military operation or military tactics used specifically to probe an enemys disposition
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Electronic countermeasures
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An electronic countermeasure is an electrical or electronic device designed to trick or deceive radar, sonar or other detection systems, like infrared or lasers. It may be used offensively and defensively to deny targeting information to an enemy. The system may make many separate targets appear to the enemy and it is used effectively to protect aircraft from guided missiles. Most air forces use ECM to protect their aircraft from attack and it has also been deployed by military ships and recently on some advanced tanks to fool laser/IR guided missiles. It is frequently coupled with stealth advances so that the ECM systems have an easier job, offensive ECM often takes the form of jamming. Defensive ECM includes using blip enhancement and jamming of missile terminal homers, first example of electronic countermeasures being applied in a combat situation took place during the Russo-Japanese war. The spark-gap transmitters in the Russian stations generated senseless noise while the Japanese were making attempts to coordinate their efforts in the bombing of a Russian naval base. Germany and United Kingdom interfered with enemy communications along the front during World War I while the Royal Navy tried to intercept German naval radio transmissions. There were also efforts at sending false radio signals, having shore stations send transmissions using ships call signs, World War II ECM expanded to include dropping chaff, jamming and spoofing radar and navigation signals. German bomber aircraft navigated using radio signals transmitted from ground stations, cold War developments included anti-radiation missiles designed to home in on enemy radar transmitters. In the 2007 Operation Orchard Israeli attack on a suspected Syrian nuclear weapons site, Israeli electronic warfare systems took over Syria’s air defense systems, feeding them a false sky-picture while Israel Air Force jets crossed much of Syria, bombed their targets and returned. Basic radar ECM strategies are radar interference, target modifications, interference techniques include jamming and deception. Jamming is accomplished by a friendly platform transmitting signals on the frequency to produce a noise level sufficient to hide echos. The jammers continuous transmissions will provide a clear direction to the enemy radar, deception may use a transponder to mimic the radar echo with a delay to indicate incorrect range. Transponders may alternatively increase return echo strength to make a small decoy appear to be a larger target, target modifications include radar absorbing coatings and modifications of the surface shape to either stealth a high-value target or enhance reflections from a decoy. Dispersal of small aluminium strips called chaff is a method of changing the electromagnetic properties of air to provide confusing radar echos. ECM is practiced by all modern military units—land, sea or air. Aircraft, however, are the weapons in the ECM battle because they can see a larger patch of earth than a sea or land-based unit
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