|
GBU-12 Paveway II
The GBU-12 Paveway II is an American aerial laser-guided bomb, based on the Mk 82 500-pound (227 kg) general-purpose bomb, but with the addition of a nose-mounted laser seeker and fins for guidance. A member of the Paveway series of weapons, Paveway II entered into service c. 1976. It is currently in service with the U.S. Air Force, U.S. Navy, U.S. Marine Corps, and various other air forces. Development and deployment The development of the GBU-12 traces back to the Vietnam War. The U.S. Air Force wanted a greater variety of laser-guided bombs, especially a lighter and more maneuverable one to be able to hit moving targets on the Ho Chi Minh trail. Earlier designs of guided bombs such as the BOLT-117 were quickly superseded by the Paveway series of add-on kits for conventional bombs. GBU-12 bombs (along with the balance of the Paveway series) are produced by defense contractors Lockheed Martin and Raytheon. Raytheon began production after purchasing the product line from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gulf War
The Gulf War was a 1990–1991 armed campaign waged by a 35-country military coalition in response to the Iraqi invasion of Kuwait. Spearheaded by the United States, the coalition's efforts against Iraq were carried out in two key phases: Operation Desert Shield, which marked the military buildup from August 1990 to January 1991; and Operation Desert Storm, which began with the aerial bombing campaign against Iraq on 17 January 1991 and came to a close with the American-led Liberation of Kuwait on 28 February 1991. On 2 August 1990, Iraq invaded the neighbouring State of Kuwait and had fully occupied the country within two days. Initially, Iraq ran the occupied territory under a puppet government known as the "Republic of Kuwait" before proceeding with an outright annexation in which Kuwaiti sovereign territory was split, with the "Saddamiyat al-Mitla' District" being carved out of the country's northern portion and the "Kuwait Governorate" covering the rest. Varying spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sine Wave
A sine wave, sinusoidal wave, or just sinusoid is a curve, mathematical curve defined in terms of the ''sine'' trigonometric function, of which it is the graph of a function, graph. It is a type of continuous wave and also a Smoothness, smooth periodic function. It occurs often in mathematics, as well as in physics, engineering, signal processing and many other fields. Formulation Its most basic form as a function of time (''t'') is: y(t) = A\sin(2 \pi f t + \varphi) = A\sin(\omega t + \varphi) where: * ''A'', ''amplitude'', the peak deviation of the function from zero. * ''f'', ''frequency, ordinary frequency'', the ''Real number, number'' of oscillations (cycles) that occur each second of time. * ''ω'' = 2''f'', ''angular frequency'', the rate of change of the function argument in units of radians per second. * \varphi, ''phase (waves), phase'', specifies (in radians) where in its cycle the oscillation is at ''t'' = 0. When \varphi is non-zero, the entire waveform appears to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bang–bang Control
In control theory, a bang–bang controller (2 step or on–off controller), is a feedback controller that switches abruptly between two states. These controllers may be realized in terms of any element that provides hysteresis. They are often used to control a plant that accepts a binary input, for example a furnace that is either completely on or completely off. Most common residential thermostats are bang–bang controllers. The Heaviside step function in its discrete form is an example of a bang–bang control signal. Due to the discontinuous control signal, systems that include bang–bang controllers are variable structure systems, and bang–bang controllers are thus variable structure controllers. Bang–bang solutions in optimal control In optimal control problems, it is sometimes the case that a control is restricted to be between a lower and an upper bound. If the optimal control switches from one extreme to the other (i.e., is strictly never in between the bounds), t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unguided Bomb
An unguided bomb, also known as a free-fall bomb, gravity bomb, dumb bomb, or iron bomb, is a conventional or nuclear aircraft-delivered bomb that does not contain a guidance system and hence simply follows a ballistic trajectory. This described all aircraft bombs in general service until the latter half of World War II, and the vast majority until the late 1980s. Then, with the dramatically increased use of precision-guided munitions, a retronym was needed to separate "smart bombs" from free-fall bombs. "Dumb bomb" was used for a time, but many military circles felt it sounded too trite, and eventually "gravity bomb" gained popularity. Bomb casings for unguided bombs are typically aerodynamic in shape, often with fins at the tail section, which reduce drag and increase stability after release, both of which serve to improve accuracy and consistency of trajectory. Unguided bombs typically use a contact fuze for detonation upon impact, or some milliseconds after if a penetration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circular Error Probable
In the military science of ballistics, circular error probable (CEP) (also circular error probability or circle of equal probability) is a measure of a weapon system's precision. It is defined as the radius of a circle, centered on the mean, whose perimeter is expected to include the landing points of 50% of the rounds; said otherwise, it is the median error radius. That is, if a given munitions design has a CEP of 100 m, when 100 munitions are targeted at the same point, 50 will fall within a circle with a radius of 100 m around their average impact point. (The distance between the target point and the average impact point is referred to as bias.) There are associated concepts, such as the DRMS (distance root mean square), which is the square root of the average squared distance error, and R95, which is the radius of the circle where 95% of the values would fall in. The concept of CEP also plays a role when measuring the accuracy of a position obtained by a navigati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guided Munition
A precision-guided munition (PGM, smart weapon, smart munition, smart bomb) is a guided munition intended to precisely hit a specific target, to minimize collateral damage and increase lethality against intended targets. During the First Gulf War guided munitions accounted for only 9% of weapons fired, but accounted for 75% of all successful hits. Despite guided weapons generally being used on more difficult targets, they were still 35 times more likely to destroy their targets per weapon dropped. Because the damage effects of explosive weapons decrease with distance due to an inverse cube law, even modest improvements in accuracy (hence reduction in miss distance) enable a target to be attacked with fewer or smaller bombs. Thus, even if some guided bombs miss, fewer air crews are put at risk and the harm to civilians and the amount of collateral damage may be reduced. The advent of precision-guided munitions resulted in the renaming of older, low-technology, bombs as "ungui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The first laser was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow. A laser differs from other sources of light in that it emits light which is ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling applications such as laser cutting and lithography. Spatial coherence also allows a laser beam to stay narrow over great distances (collimation), enabling applications such as laser pointers and lidar (light detection and ranging). Lasers can also have high temporal coherence, which allows them to emit light with a very narrow spectrum. Alternatively, temporal coherence can be used to produce ultrashort pulses of ligh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smart Bomb
Smart or SMART may refer to: Arts and entertainment * ''Smart'' (Hey! Say! JUMP album), 2014 * Smart (Hotels.com), former mascot of Hotels.com * ''Smart'' (Sleeper album), 1995 debut album by Sleeper * ''SMart'', a children's television series about art on CBBC Businesses and brands * S-Mart, a Mexican grocery store chain * SMART (advertising agency), an Australian company * SmartCell, a network operator in Nepal * Smart Communications, a cellular service provider in the Philippines * Smart Technologies, a company providing group collaboration tools * Smart Telecom, a network operator in the Republic of Ireland * Smart (cigarette), an Austrian brand * Smart (drink), a brand of fruit-flavored soda produced by The Coca-Cola Company for Mainland China Computing * Smart device, an electronic device connected to other devices or networks wirelessly * Self-Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.), a standard used in computer storage devices * SMART Informat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser-guided Bomb
A laser-guided bomb (LGB) is a guided bomb that uses semi-active laser guidance to strike a designated target with greater accuracy than an unguided bomb. First developed by the United States during the Vietnam War, laser-guided bombs quickly proved their value in precision strikes of difficult point targets. These weapons use on-board electronics to track targets that are designated by laser, typically in the infrared spectrum, and adjust their glide path to accurately strike the target. Since the weapon is tracking a light signature, not the object itself, the target must be illuminated from a separate source, either by ground forces, by a pod on the attacking aircraft, or by a separate support aircraft. Data from the 28,000 laser guided bombs dropped in Vietnam showed that laser-guided bombs achieved direct hits nearly 50% of the time, despite the laser having to be aimed out the side window of the back seat of another aircraft in flight. Unguided bombs had an accuracy rate o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Department Of Defense
The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national security and the United States Armed Forces. The DoD is the largest employer in the world, with over 1.34 million active-duty service members (soldiers, marines, sailors, airmen, and guardians) as of June 2022. The DoD also maintains over 778,000 National Guard and reservists, and over 747,000 civilians bringing the total to over 2.87 million employees. Headquartered at the Pentagon in Arlington, Virginia, just outside Washington, D.C., the DoD's stated mission is to provide "the military forces needed to deter war and ensure our nation's security". The Department of Defense is headed by the secretary of defense, a cabinet-level head who reports directly to the president of the United States. Beneath the Department of Defense are th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F/A-18
The McDonnell Douglas F/A-18 Hornet is an all-weather, twin-engine, supersonic, carrier-capable, multirole combat aircraft, designed as both a fighter and attack aircraft (hence the F/A designation). Designed by McDonnell Douglas (now part of Boeing) and Northrop (now part of Northrop Grumman), the F/A-18 was derived from the latter's YF-17 in the 1970s for use by the United States Navy and Marine Corps. The Hornet is also used by the air forces of several other nations, and formerly by the U.S. Navy's Flight Demonstration Squadron, the Blue Angels. The F/A-18 was designed to be a highly versatile aircraft due to its avionics, cockpit displays, and excellent aerodynamic characteristics, with the ability to carry a wide variety of weapons. The aircraft can perform fighter escort, fleet air defense, suppression of enemy air defenses, air interdiction, close air support, and aerial reconnaissance. Its versatility and reliability have proven it to be a valuable carrier asse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
