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Rolleron
A rolleron is a type of aileron used for rockets and used to provide passive stabilization against rotation. While most commonly used to stabilize against Aircraft_principal_axes#Longitudinal_axis_(roll), roll, it can also be used for counteracting Aircraft_principal_axes#Vertical_axis_(yaw), yaw and Aircraft_principal_axes#Transverse_axis_(pitch), pitch as well. In the early 1950s, the first rollerons were produced. Its value for the dynamic stabilization of missiles led to it being promptly studied by the National Advisory Committee for Aeronautics (NACA). It proved to be a more compact, simpler, and reliable solution to controlling roll than preceding methods, such as the combination of servomechanisms and ailerons. Rolleron devices have been widely used on maneuverable close-range air-to-air missiles, such as the prolific AIM-9 Sidewinder. Rocket vehicles have also become another common application. History During the early 1950s, the first examples of the rolleron, sometime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
9K31 Strela-1
The 9K31 ''Strela-1'' (; ) is a highly mobile, short-range, low altitude infra-red guided surface-to-air missile system. Originally developed by the Soviet Union under the GRAU designation 9K31, it is commonly known by its NATO reporting name, SA-9 " Gaskin". The system consists of a BRDM-2 amphibious vehicle, mounting two pairs of ready-to-fire 9M31 missiles. Development history The missiles used in this system were developed alongside the ubiquitous Soviet MANPADS 9K32M "Strela-2" (NATO designation SA-7 "Grail") in the 1960s. At first, both missiles were intended to be man-portable systems, but as it became obvious that the Strela-2 would be far more compact, the development goals of Strela-1 were changed. Instead of a battalion-level man-portable system the new criteria called for a regimental vehicle-mounted SAM to support the ZSU-23-4. As a result of the change in role and more relaxed weight limits of a vehicle-mounted SAM, the design team made the 9M31 a much heavier mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
AIM-9 Sidewinder
The AIM-9 Sidewinder is a short-range air-to-air missile. Entering service with the United States Navy in 1956 and the Air Force in 1964, the AIM-9 is one of the oldest, cheapest, and most successful air-to-air missiles. Its latest variants remain standard equipment in most Western-aligned air forces. The Soviet K-13 (AA-2 "Atoll"), a reverse-engineered copy of the AIM-9B, was also widely adopted. Low-level development started in the late 1940s, emerging in the early 1950s as a guidance system for the modular Zuni rocket. This modularity allowed for the introduction of newer seekers and rocket motors, including the AIM-9C variant, which used semi-active radar homing and served as the basis of the AGM-122 Sidearm anti-radar missile. Due to the Sidewinder's infrared guidance system, the brevity code " Fox two" is used when firing the AIM-9. Originally a tail-chasing system, early models saw extensive use during the Vietnam War, but had a low success rate (8% hit rate with th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Henry Spencer
Henry Spencer (born 1955) is a Canadian computer programmer and space enthusiast. He wrote "regex", a widely used software library for regular expressions, and co-wrote C News, a Usenet server program. He also wrote ''The Ten Commandments for C Programmers''. He is coauthor, with David Lawrence, of the book ''Managing Usenet''. While working at the University of Toronto he ran the first active Usenet site outside the U.S., starting in 1981. His records from that period were eventually acquired by Google to provide an archive of Usenet in the 1980s. The first international Usenet site was run in Ottawa, in 1981; however, it is generally not remembered, as it served merely as a read-only medium. Later in 1981, Spencer acquired a Usenet feed from Duke University, and brought "utzoo" online; the earliest public archives of Usenet date from May 1981 as a result. The small size of Usenet in its youthful days, and Spencer's early involvement, made him a well-recognised participant; th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Aircraft Wing Components
An aircraft ( aircraft) is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or the Lift (force), dynamic lift of an airfoil, or, in a few cases, direct Powered lift, downward thrust from its engines. Common examples of aircraft include airplanes, rotorcraft (including helicopters), airships (including blimps), Glider (aircraft), gliders, Powered paragliding, paramotors, and hot air balloons. Part 1 (Definitions and Abbreviations) of Subchapter A of Chapter I of Title 14 of the U. S. Code of Federal Regulations states that aircraft "means a device that is used or intended to be used for flight in the air." The human activity that surrounds aircraft is called ''aviation''. The science of aviation, including designing and building aircraft, is called ''aeronautics.'' Aircrew, Crewed aircraft are flown by an onboard Aircraft pilot, pilot, whereas unmanned aerial vehicles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Aerodynamics
Aerodynamics () is the study of the motion of atmosphere of Earth, air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics. The term ''aerodynamics'' is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving Aircraft#Heavier-than-air – aerodynes, heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dogfight
A dogfight, or dog fight, is an air combat manoeuvring, aerial battle between fighter aircraft that is conducted at close range. Modern terminology for air-to-air combat is air combat manoeuvring (ACM), which refers to tactical situations requiring the use of individual basic fighter maneuvers (BFM) to attack or evade one or more opponents. This differs from aerial warfare, which deals with the strategy involved in planning and executing various missions. Dogfighting first occurred during the Mexican Revolution in 1913, shortly after the invention of the airplane. It was a component of every major war after that, though with steadily declining frequency, until the end of the Cold War in the early 1990s. Since then, longer-range weapons such as beyond-visual-range missiles have made dogfighting largely obsolete. Etymology The term ''dogfight'' has been used for centuries to describe a melee: a fierce, fast-paced close quarters battle, battle at close quarters between two or mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gyroscope
A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining Orientation (geometry), orientation and angular velocity. It is a spinning wheel or disc in which the axis of rotation (spin axis) is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of the mounting, due to the angular momentum#Conservation of angular momentum, conservation of angular momentum. Gyroscopes based on other operating principles also exist, such as the microchip-packaged Vibrating structure gyroscope#MEMS gyroscopes, MEMS gyroscopes found in electronic devices (sometimes called gyrometers), solid-state ring laser gyroscope, ring lasers, fibre optic gyroscopes, and the extremely sensitive quantum gyroscope. Applications of gyroscopes include inertial navigation systems, such as in the Hubble Space Telescope, or inside the steel hull of a submer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
9K35 Strela-10
The 9K35 ''Strela-10'' (; ) is a Soviet highly mobile, short-range surface-to-air missile system. It is visually aimed, and utilizes optical/ infrared-guidance. The system is primarily intended to engage low-altitude threats, such as helicopters. "9K35" is its GRAU designation; its NATO reporting name is SA-13 "Gopher". Development The 9K35 is the successor of the 9K31 Strela-1 and can also use the Strela-1's missiles in place of the 9M37. Development of the 9K37 Strela-10SV system was initiated July 24, 1969. The decision to begin the development of a new non-all-weather system was taken despite the simultaneous development of an all-weather hybrid gun/missile system 2K22 "Tunguska" mainly as an economical measure. It was also seen as advantageous to have a system capable of fast reaction times and immunity to heavy radio-frequency jamming. Rather than being mounted on an amphibious but lightly armoured BRDM chassis like the 9K31, the 9K35 is mounted on a more mobile tracked, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Newsgroup
A Usenet newsgroup is a repository usually within the Usenet system for messages posted from users in different locations using the Internet. They are not only discussion groups or conversations, but also a repository to publish articles, start developing tasks like creating Linux, sustain mailing lists and file uploading. That’s thank to the protocol that poses no article size limit, but are to the providers to decide. In the late 1980s, Usenet articles were often limited by the providers to 60,000 characters, but in time, Usenet groups have been split into two types: ''text'' for mainly discussions, conversations, articles, limited by most providers to about 32,000 characters, and ''binary'' for file transfer, with providers setting limits ranging from less than 1 MB to about 4 MB. Newsgroups are technically distinct from, but functionally similar to, discussion forums on the World Wide Web. Newsreader software is used to read the content of newsgroups. Before the adoption ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Flywheel
A flywheel is a mechanical device that uses the conservation of angular momentum to store rotational energy, a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, assuming the flywheel's moment of inertia is constant (i.e., a flywheel with fixed mass and second moment of area revolving about some fixed axis) then the stored (rotational) energy is directly associated with the square of its rotational speed. Since a flywheel serves to store mechanical energy for later use, it is natural to consider it as a kinetic energy analogue of an electrical Inductor. Once suitably abstracted, this shared principle of energy storage is described in the generalized concept of an accumulator. As with other types of accumulators, a flywheel inherently smooths sufficiently small deviations in the power output of a system, thereby effectively playing the role of a low-pass filter with respect to the mechanical veloc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
