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Contrast Seeker
Optical contrast seekers, or simply contrast seekers, are a type of missile guidance system using a television camera as its primary input. The camera is initially pointed at a target and then locked on, allowing the missile to fly to its target by keeping the image stable within the camera's field of view. The first production missile to use a contrast seeker was the AGM-65 Maverick, which began development in the 1960s and entered service in 1972. The system has not been widely used, as other guidance technologies like laser guidance and GPS have become more common, but the same basic concept is used in cameras to track objects, including the systems used to aim the laser designators. Contrast seekers should be distinguished from television guidance systems, in which a live television signal is broadcast to the launch platform, which then uses manual direction to attack the target. Examples of TV guidance include the Martel and AGM-62 Walleye. The term "contrast contour" is som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proportional Navigation
For example, if the line of sight rotates slowly from north to east, the missile should turn to the right by a certain factor faster than the LOS-rate. This factor is ''N''. Proportional navigation (also known as PN or Pro-Nav) is a guidance law (analogous to proportional control) used in some form or another by most homing air target missiles.Yanushevsky, page 3. It is based on the fact that two vehicles are on a collision course when their direct line-of-sight does not change direction as the range closes. PN dictates that the missile velocity vector should rotate at a rate proportional to the rotation rate of the line of sight (Line-Of-Sight rate or LOS-rate), and in the same direction. : a_n = N\dot \lambda V Where a_n is the acceleration perpendicular to the missile's instantaneous velocity vector, N is the proportionality constant generally having an integer value 3-5 (dimensionless), \dot \lambda is the line of sight rate, and V is the closing velocity. Since the line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mark 118 Bomb
The M118 is an air-dropped general-purpose or demolition bomb used by United States military forces. It dates back to the time of the Korean War of the early 1950s. Although it has a nominal weight of 3,000 lb (1,350 kg), its actual weight, depending on fuse and retardation options, is somewhat higher. A typical non-retarded configuration has a total weight of 3,049 lb (1,383 kg) with an explosive content of 1,975 lb (895 kg) of tritonal. This is a higher percentage than in the more recent American Mark 80 series bombs thus perhaps the designation as a demolition bomb. In the late 1950s through the early 1970s it was a standard aircraft weapon, carried by the F-100 Super Sabre, F-104 Starfighter, F-105 Thunderchief, and F-4 Phantom. Some apparently remain in the USAF inventory, although they are rarely used today. It was a component of the GBU-9/B version of the Rockwell electro-optically guided Homing Bomb System (HOBOS). This weapon consisted of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GBU-8
The GBU-8 Homing Bomb System (HOBOS) is a 2000 lb Electro-Optical guided bomb developed for the United States Air Force. Description The GBU-8 consists of a contrast seeker in the nose section, four cruciform tailfins with flying surfaces for control, strakes connecting the tailfins with the nose section, and a 2000 lb Mk. 84 LDGP bomb. The same type of guidance kit was also attached to a 3000 lb Mark 118 bomb, where it was designated GBU-9. History Development of the Homing Bomb System (HOBOS) by Rockwell began in 1967 on the request of the U.S. Air Force in response to shortcomings of the AGM-62 Walleye during the Vietnam War. The payload of the 2000 lb Mk. 84 bomb was considered to be more effective than the smaller explosive warhead found on the Walleye, which was designed by the Navy for anti-ship use. The system was deployed to Ubon, Thailand in January 1969 and was subsequently used in combat for the first time in February 1969. The HOBOS system was also used in O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mark 84 Bomb
The Mark 84 or BLU-117 is an American general-purpose bomb. It is the largest of the Mark 80 series of weapons. Entering service during the Vietnam War, it became a commonly used US heavy unguided bomb (due to the amount of high-explosive content packed inside) to be dropped. At the time, it was the third largest bomb by weight in the US inventory behind the BLU-82 "Daisy Cutter" and the Mark 118 bomb, M118 "demolition" bomb. It is currently sixth in size due to the addition of the GBU-28 in 1991, the GBU-43/B Massive Ordnance Air Blast bomb (MOAB) in 2003, and the Massive Ordnance Penetrator. Development The Mark 84 has a nominal weight of , but its actual weight varies depending on its fin, fuze options, and retardation configuration, from . It is a streamlined steel casing filled with of Tritonal high explosive. The Mark 84 is capable of forming a crater wide and deep. It can penetrate up to of metal or of concrete, depending on the height from which it is dro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operation Linebacker
Operation Linebacker was the codename of a U.S. Seventh Air Force and U.S. Navy Task Force 77 air interdiction campaign conducted against North Vietnam from 9 May to 23 October 1972, during the Vietnam War. Its purpose was to halt or slow the transportation of supplies and materials for the ''Nguyen Hue Offensive'' (known in the West as the Easter Offensive), an invasion of the South Vietnam by the North Vietnamese People's Army of Vietnam (PAVN) that had been launched on 30 March. ''Linebacker'' was the first continuous bombing effort conducted against North Vietnam since the end of Operation Rolling Thunder in November 1968. Nguyen Hue Offensive At midday on 30 March 1972, 30,000 PAVN troops, supported by regiments of tanks and artillery, rolled southward across the Demilitarized Zone (DMZ) that separated the two Vietnams. This three-division force caught the Army of the Republic of Vietnam (ARVN) and their American allies unprepared. The PAVN force struck the defensive pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vietnam War
The Vietnam War (also known by #Names, other names) was a conflict in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vietnam and South Vietnam. The north was supported by the Soviet Union, China, and other communist states, while the south was United States in the Vietnam War, supported by the United States and other anti-communism, anti-communist Free World Military Forces, allies. The war is widely considered to be a Cold War-era proxy war. It lasted almost 20 years, with direct U.S. involvement ending in 1973. The conflict also spilled over into neighboring states, exacerbating the Laotian Civil War and the Cambodian Civil War, which ended with all three countries becoming communist states by 1975. After the French 1954 Geneva Conference, military withdrawal from Indochina in 1954 – following their defeat in the First Indochina War – the Viet Minh to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Control
Radio control (often abbreviated to RC) is the use of control signals transmitted by radio to remotely control a device. Examples of simple radio control systems are garage door openers and keyless entry systems for vehicles, in which a small handheld radio transmitter unlocks or opens doors. Radio control is also used for control of model vehicles from a hand-held radio transmitter. Industrial, military, and scientific research organizations make use of radio-controlled vehicles as well. A rapidly growing application is control of unmanned aerial vehicles (UAVs or drones) for both civilian and military uses, although these have more sophisticated control systems than traditional applications. History The idea of controlling unmanned vehicles (for the most part in an attempt to improve the accuracy of torpedoes for military purposes) predates the invention of radio. The latter half of the 1800s saw development of many such devices, connected to an operator by wires, inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manual Command To Line Of Sight
Manual command to line of sight (MCLOS) is a method for guiding guided missiles. With an MCLOS missile, the operator must track the missile and the target simultaneously and guide the missile to the target. Typically the missile is steered with a joystick, and its path is observed through a periscope-type telescopic sight. The missiles are usually equipped with a magnesium flare in the base that automatically ignites on launch and allows the gunner to visually track the fast-moving missile in a manner similar in concept to tracer ammunition. MCLOS requires considerable training and practice to master, since even a minor disruption in the gunner's concentration would likely cause a miss. These guidance systems have marginal accuracy on tank-sized targets, even with perfect line-of-sight by the gunner, due to erratic flight paths requiring timely manual corrections. As demonstrated by the Israeli Army under fire from Soviet-armed Arab states, responding to the distinctive smoke puff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Homing
Infrared homing is a passive weapon guidance system which uses the infrared (IR) light emission from a target to track and follow it seamlessly. Missiles which use infrared seeking are often referred to as "heat-seekers" since infrared is radiated strongly by hot bodies. Many objects such as people, vehicle engines and aircraft generate and emit heat and so are especially visible in the infrared wavelengths of light compared to objects in the background. Infrared seekers are passive devices, which, unlike radar, provide no indication that they are tracking a target. That makes them suitable for sneak attacks during visual encounters or over longer ranges when they are used with a forward looking infrared or similar cuing system. Heat-seekers are extremely effective: 90% of all United States air combat losses over the past 25 years have been caused by infrared-homing missiles. They are, however, subject to a number of simple countermeasures, most notably by dropping flares beh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-active Radar Homing
Semi-active radar homing (SARH) is a common type of missile guidance system, perhaps the most common type for longer-range Air-to-air missile, air-to-air and surface-to-air missile systems. The name refers to the fact that the missile itself is only a passive radar, passive detector of a radar signal—Radar illumination, provided by an external ("offboard") source—as it reflects off the target (in contrast to active radar homing, which uses an active radar transceiver). Semi-active missile systems use bistatic radar, bistatic continuous-wave radar. The NATO Multiservice tactical brevity code, brevity code for a semi-active radar homing missile launch is Fox (code word), Fox One. Concept The basic concept of SARH is that since almost all detection and tracking systems consist of a radar system, duplicating this hardware on the missile itself is redundant. The weight of a transmitter reduces the range of any flying object, so passive systems have greater reach. In addition, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AGM-65 M-48 Pre Impact
The AGM-65 Maverick is an air-to-ground missile (AGM) designed for close air support. It is the most widely produced precision-guided missile in the Western world, and is effective against a wide range of tactical targets, including armor, air defenses, ships, ground transportation and fuel storage facilities. Development began in 1966 at Hughes Aircraft Company as the first missile to use an electronic contrast seeker. It entered service with the United States Air Force in August 1972. Since then, it has been exported to more than 30 countries and is certified on 25 aircraft. The Maverick served during the Vietnam, Yom Kippur, Iran–Iraq, and Persian Gulf Wars, along with other smaller conflicts, destroying enemy forces and installations with varying degrees of success. Since its introduction into service, numerous Maverick versions had been designed and produced using electro-optical, laser, and imaging infrared guidance systems. The AGM-65 has two types of warhead: one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
