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Laser Gun
A laser weapon is a directed-energy weapon based on lasers. After decades of R&D, directed-energy weapons including lasers are still at the experimental stage and it remains to be seen if or when they will be deployed as practical, high-performance military weapons. Atmospheric thermal blooming has been a major problem, still mostly unsolved, and worsened if fog, smoke, dust, rain, snow, smog, foam, or purposely dispersed obscurant chemicals are present. Essentially, a laser generates a beam of light which needs clear air, or a vacuum, to work without thermal blooming. Many types of laser can potentially be used as incapacitating weapons, through their ability to produce temporary or permanent vision loss when aimed at the eyes. The degree, character, and duration of vision impairment caused by eye exposure to laser light varies with the power of the laser, the wavelength(s), the collimation of the beam, the exact orientation of the beam, and the duration of exposure. Lasers o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lasers And Aviation Safety
Under certain conditions, laser light or other bright lights (spotlights, searchlights) directed at aircraft can be a hazard. The most likely scenario is when a bright visible laser light causes distraction or temporary flash blindness to a pilot, during a critical phase of flight such as landing or takeoff. It is far less likely, though still possible, that a visible or invisible beam could cause permanent harm to a pilot's eyes. Although laser weapons are under development by armed forces, these are so specialized, expensive and controlled that it is improbable for non-military lasers to cause structural damage to an aircraft. Pointing a laser at an aircraft can be hazardous to pilots, and has resulted in arrests, trials and jail sentences. It also results in calls to license or ban laser pointers. Some jurisdictions such as New South Wales, Australia have restricted laser pointers as a result of multiple incidents. Lasers and bright lights In addition to lasers, other brigh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strategic Defense Initiative
The Strategic Defense Initiative (SDI), derisively nicknamed the "''Star Wars'' program", was a proposed missile defense system intended to protect the United States from attack by ballistic strategic nuclear weapons (intercontinental ballistic missiles and submarine-launched ballistic missiles). The concept was announced on March 23, 1983, by President Ronald Reagan,Federation of American ScientistsMissile Defense Milestones Accessed March 10, 2007. a vocal critic of the doctrine of mutually assured destruction (MAD), which he described as a " suicide pact". Reagan called upon American scientists and engineers to develop a system that would render nuclear weapons obsolete. The Strategic Defense Initiative Organization (SDIO) was set up in 1984 within the US Department of Defense to oversee development. A wide array of advanced weapon concepts, including lasers, Duarte, F. J. (Ed.), ''Proceedings of the International Conference on Lasers '87'' (STS, McLean, Va, 1988). particle be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing YAL-1
The Boeing YAL-1 Airborne Laser Testbed (formerly Airborne Laser) weapons system was a megawatt-class chemical oxygen iodine laser (COIL) mounted inside a modified military Boeing 747-400F. It was primarily designed as a missile defense system to destroy tactical ballistic missiles (TBMs) while in boost phase. The aircraft was designated YAL-1A in 2004 by the U.S. Department of Defense. The YAL-1 with a low-power laser was test-fired in flight at an airborne target in 2007. A high-energy laser was used to intercept a test target in January 2010, and the following month, successfully destroyed two test missiles. Funding for the program was cut in 2010 and the program was canceled in December 2011. It made its final flight on February 14, 2012, to Davis–Monthan Air Force Base in Tucson, Arizona, to be kept in storage at the "Boneyard" by the 309th Aerospace Maintenance and Regeneration Group. It was ultimately scrapped in September 2014 after all usable parts were removed. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Beam Welding
Laser beam welding (LBW) is a welding technique used to join pieces of metal or thermoplastics through the use of a laser. The beam provides a concentrated heat source, allowing for narrow, deep welds and high welding rates. The process is frequently used in high volume and precision requiring applications using automation, as in the automotive and aeronautics industries. It is based on keyhole or penetration mode welding. Operation Like electron-beam welding (EBW), laser beam welding has high power density (on the order of 1 MW/cm2) resulting in small heat-affected zones and high heating and cooling rates. The spot size of the laser can vary between 0.2 mm and 13 mm, though only smaller sizes are used for welding. The depth of penetration is proportional to the amount of power supplied, but is also dependent on the location of the focal point: penetration is maximized when the focal point is slightly below the surface of the workpiece A continuous or pulsed laser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Broadcasting Company
The American Broadcasting Company (ABC) is an American commercial broadcast television network. It is the flagship property of the ABC Entertainment Group division of The Walt Disney Company. The network is headquartered in Burbank, California, on Riverside Drive, directly across the street from Walt Disney Studios and adjacent to the Roy E. Disney Animation Building. The network's secondary offices, and headquarters of its news division, are in New York City, at its broadcast center at 77 West 66th Street on the Upper West Side of Manhattan. Since 2007, when ABC Radio (also known as Cumulus Media Networks) was sold to Citadel Broadcasting, ABC has reduced its broadcasting operations almost exclusively to television. It is the fifth-oldest major broadcasting network in the world and the youngest of the American Big Three television networks. The network is sometimes referred to as the Alphabet Network, as its initialism also represents the first three letters of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of STOL (Short TakeOff and Landing) or STOVL (Short TakeOff and Vertical Landing) aircraft cannot perform without a runway. In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production.Munson 1968.Hirschberg, Michael J. and David K. Dailey"Sikorsky". ''US and Russian Helicopter Development in the 20th Century'', American Helicopter Society, International. 7 July 2000. Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter, not to be confused with the single-blade monocopter) has become the most comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motorboat
A motorboat, speedboat or powerboat is a boat that is exclusively powered by an engine. Some motorboats are fitted with inboard engines, others have an outboard motor installed on the rear, containing the internal combustion engine, the gearbox and the propeller in one portable unit. An inboard-outboard contains a hybrid of an inboard and an outboard, where the internal combustion engine is installed inside the boat, and the gearbox and propeller are outside. There are two configurations of an inboard, V-drive and direct drive. A direct drive has the powerplant mounted near the middle of the boat with the propeller shaft straight out the back, where a V-drive has the powerplant mounted in the back of the boat facing backwards having the shaft go towards the front of the boat then making a ''V'' towards the rear. Overview A motorboat has one or more engines that propel the vessel over the top of the water. Boat engines vary in shape, size, and type. Engines are installed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket-propelled Grenades
A rocket-propelled grenade (RPG) is a shoulder-fired missile weapon that launches rockets equipped with an explosive warhead. Most RPGs can be carried by an individual soldier, and are frequently used as anti-tank weapons. These warheads are affixed to a rocket motor which propels the RPG towards the target and they are stabilized in flight with fins. Some types of RPG are reloadable with new rocket-propelled grenades, while others are single-use. RPGs are generally loaded from the front. RPGs with high-explosive anti-tank (HEAT) warheads are very effective against lightly armored vehicles such as armored personnel carriers (APCs) and armored cars. However, modern, heavily-armored vehicles, such as upgraded APCs and main battle tanks, are generally too well-protected (with thick composite or reactive armor) to be penetrated by an RPG, unless less armored sections of the vehicle are exploited. Various warheads are also capable of causing secondary damage to vulnerable system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Weapon System
The AN/SEQ-3 Laser Weapon System or XN-1 LaWS is a laser weapon developed by the United States Navy. The weapon was installed on for field testing in 2014. In December 2014, the United States Navy reported that the LaWS system worked perfectly against low-end asymmetric threats, and that the commander of ''Ponce'' was authorized to use the system as a defensive weapon. Purpose The LaWS is a ship-defense system that has so far publicly engaged an unmanned aerial vehicle (UAV or drone) and a simulated small-boat attacker. LaWS uses an infrared beam from a solid-state laser array which can be tuned to high output to destroy a target or low output to warn or cripple the sensors of a target. One of its advantages over projectile weapons is the low cost per shot: Each firing of the weapon requires only the minimal cost of generating the energetic pulse; by contrast, ordnance for projectile weapons must be designed, manufactured, handled, transported, and maintained, and takes up sto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilowatt
The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution. Overview When an object's velocity is held constant at one metre per second against a constant opposing force of one newton, the rate at which work is done is one watt. : \mathrm In terms of electromagnetism, one watt is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). : ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of its active battle fleet alone exceeding the next 13 navies combined, including 11 allies or partner nations of the United States as of 2015. It has the highest combined battle fleet tonnage (4,635,628 tonnes as of 2019) and the world's largest aircraft carrier fleet, with eleven in service, two new carriers under construction, and five other carriers planned. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the United States Navy is the third largest of the United States military service branches in terms of personnel. It has 290 deployable combat vessels and more than 2,623 operational aircraft . The United States Navy traces its origins to the Continental Navy, which was established during the American Revo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
