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14-inch M1920 Railway Gun
The 14-inch M1920 railway gun was the last model railway gun to be deployed by the United States Army. It was an upgrade of the US Navy 14"/50 caliber railway gun. Only four were deployed; two in the Harbor Defenses of Los Angeles and two in the Panama Canal Zone, where they could be shifted between the harbor defenses of Cristobal (Atlantic) or Balboa (Pacific). History After the close of World War I, the US Army wanted to incorporate the lessons learned from other railway gun mounts and fulfill coastal artillery requirements for hitting a moving target. An effort to design a more universal mount for the Navy's Mk. IV 14"/50 caliber gun was undertaken. The primary difference from the earlier Navy versions lies in the M1920 carriage, which could be raised and lowered. Prepositioned fixed mounts were installed at the forts, and the gun's rail trucks could be taken out from under the frame. After the removal of the rail trucks, the gun was lowered and bolted onto a pivot po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Gun
A railway gun, also called a railroad gun, is a large artillery piece, often surplus naval artillery, mounted on, transported by, and fired from a specially designed railroad car, railway wagon. Many countries have built railway guns, but the best-known are the large Krupp-built pieces used by German Reich, Germany in World War I and World War II. Smaller guns were often part of an armoured train. They were only able to be moved where there were good tracks, which could be destroyed by artillery bombardment or airstrike. Railway guns were phased out after World War II. Design considerations The design of a railway gun has three firing issues over and above those of an ordinary artillery piece to consider. Namely how the gun is going to be traversed – i.e. moved from side to side to aim; how the horizontal component of the recoil force will be absorbed by the gun's carriage and how the vertical recoil force will be absorbed by the ground. Methods of traverse The first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panama Canal Railway
The Panama Canal Railway (PCR, ) is a railway line linking the Atlantic Ocean to the Pacific Ocean in Central America. The route stretches across the Isthmus of Panama from Colón (Atlantic) to Balboa (Pacific, near Panama City). Because of the difficult physical conditions of the route and state of technology, the construction was renowned as an international engineering achievement, one that cost US$8 million and the lives of an estimated 5,000 to 10,000 workers. Opened in 1855, the railway preceded the Panama Canal by half a century; the railway was vital in assisting the construction of the canal in the early 1900s. With the opening of the canal, the railroad's route was changed as a result of the creation of Gatun Lake, which flooded part of the original route. Following World War II, the railroad's importance declined and much of it fell into a state of neglect until 1998, when a project to rebuild the railroad to haul intermodal traffic began; the new railroad opened ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Guns
A railway gun, also called a railroad gun, is a large artillery piece, often surplus naval artillery, mounted on, transported by, and fired from a specially designed railway wagon. Many countries have built railway guns, but the best-known are the large Krupp-built pieces used by Germany in World War I and World War II. Smaller guns were often part of an armoured train. They were only able to be moved where there were good tracks, which could be destroyed by artillery bombardment or airstrike. Railway guns were phased out after World War II. Design considerations The design of a railway gun has three firing issues over and above those of an ordinary artillery piece to consider. Namely how the gun is going to be traversed – i.e. moved from side to side to aim; how the horizontal component of the recoil force will be absorbed by the gun's carriage and how the vertical recoil force will be absorbed by the ground. Methods of traverse The first method of traverse is to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coastal Artillery
Coastal artillery is the branch of the armed forces concerned with operating anti-ship artillery or fixed gun batteries in coastal fortifications. From the Middle Ages until World War II, coastal artillery and naval artillery in the form of cannons were highly important to military affairs and generally represented the areas of highest technology and capital cost among materiel. The advent of 20th-century technologies, especially military aviation, naval aviation, jet aircraft, and guided missiles, reduced the primacy of cannons, battleships, and coastal artillery. In countries where coastal artillery has not been disbanded, these forces have acquired amphibious capabilities. In littoral warfare, mobile coastal artillery armed with surface-to-surface missiles can still be used to deny the use of sea lanes. It was long held as a rule of thumb that one shore-based gun equaled three naval guns of the same caliber, due to the steadiness of the coastal gun which allowed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artillery Of The United States
Artillery consists of ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and led to heavy, fairly immobile siege engines. As technology improved, lighter, more mobile field artillery cannons were developed for battlefield use. This development continues today; modern self-propelled artillery vehicles are highly mobile weapons of great versatility generally providing the largest share of an army's total firepower. Originally, the word "artillery" referred to any group of soldiers primarily armed with some form of manufactured weapon or armour. Since the introduction of gunpowder and cannon, "artillery" has largely meant cannon, and in contemporary usage, usually refers to Shell (projectile), shell-firing Field gun, guns, howitzers, and Mortar (weapon), mortars (collectively called ''barrel artillery'', ''cannon artil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound Ranging
In physics, sound is a vibration that propagates as an acoustic wave through a transmission medium such as a gas, liquid or solid. In human physiology and psychology, sound is the ''reception'' of such waves and their ''perception'' by the brain. Only acoustic waves that have frequencies lying between about 20 Hz and 20 kHz, the audio frequency range, elicit an auditory percept in humans. In air at atmospheric pressure, these represent sound waves with wavelengths of to . Sound waves above 20 kHz are known as ultrasound and are not audible to humans. Sound waves below 20 Hz are known as infrasound. Different animal species have varying hearing ranges, allowing some to even hear ultrasounds. Definition Sound is defined as "(a) Oscillation in pressure, stress, particle displacement, particle velocity, etc., propagated in a medium with internal forces (e.g., elastic or viscous), or the superposition of such propagated oscillation. (b) Auditory sensa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of U
A list is a set of discrete items of information collected and set forth in some format for utility, entertainment, or other purposes. A list may be memorialized in any number of ways, including existing only in the mind of the list-maker, but lists are frequently written down on paper, or maintained electronically. Lists are "most frequently a tool", and "one does not ''read'' but only ''uses'' a list: one looks up the relevant information in it, but usually does not need to deal with it as a whole". Lucie Doležalová,The Potential and Limitations of Studying Lists, in Lucie Doležalová, ed., ''The Charm of a List: From the Sumerians to Computerised Data Processing'' (2009). Purpose It has been observed that, with a few exceptions, "the scholarship on lists remains fragmented". David Wallechinsky, a co-author of '' The Book of Lists'', described the attraction of lists as being "because we live in an era of overstimulation, especially in terms of information, and lists help ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indirect Fire
Indirect fire is aiming and firing a projectile without relying on a direct line of sight between the gun and its target, as in the case of direct fire. Aiming is performed by calculating azimuth and inclination, and may include correcting aim by observing the fall of shot and calculating new angles. Description Indirect fire is most commonly used by field artillery and mortars (although field artillery was originally and until after World War I a direct fire weapon, hence the bullet-shields fitted to the carriages of guns such as the famous M1897 75 mm). It is also used with missiles, howitzers, rocket artillery, multiple rocket launchers, cruise missiles, ballistic missiles, naval guns against shore targets, sometimes with machine guns, and has been used with tank and anti-tank guns and by anti-aircraft guns against surface targets. There are two dimensions in aiming a weapon: * In the horizontal plane (azimuth); and * In the vertical plane (elevation), which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gun Laying
Gun laying is the process of aiming an artillery piece or turret, such as a gun, howitzer, or mortar, on land, at sea, or in air, against surface or aerial targets. It may be laying for either direct fire, where the gun is aimed directly at a target within the line-of-sight of the user, or by indirect fire, where the gun is not aimed directly at a target within the line-of-sight of the user. Indirect fire is determined from the information or data that is collected, calculated, and applied to physical coordinates to identify the location of the target by the user. The term includes automated aiming using, for example, radar-derived target data and computer-controlled guns. Description Gun laying is a set of actions to align the axis of a gun barrel so that it points in the required direction. This alignment is in the horizontal and vertical planes. A gun is "traversed" (rotated in a horizontal plane) to align it with the target, and "elevated" (moved in the vertical plane) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coincidence Rangefinder
A coincidence rangefinder or coincidence telemeter is a type of rangefinder that uses the principle of triangulation and an optical device to allow an operator to determine the distance to a visible object. There are subtypes split-image telemeter, inverted image, or double-image telemeter with different principles how two images in a single ocular are compared. Coincidence rangefinders were important elements of fire control systems for long-range naval guns and land-based coastal artillery circa 1890–1960. They were also used in rangefinder cameras. A stereoscopic rangefinder looks similar, but has two eyepieces and uses a different principle, based on binocular vision. The two can normally be distinguished at a glance by the number of eyepieces. Principle Coincidence rangefinders work through the principle of triangulation. In the pictured example, triangulation can be used to determine the range of the ship ''𝑑''. The position of the lenses ''A'' and ''B'' are known, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coast Artillery Fire Control System
In the U.S. Army Coast Artillery Corps, the term fire-control system, fire control system was used to refer to the personnel, facilities, technology and procedures that were used to observe designated targets, estimate their positions, calculate firing data for guns directed to hit those targets, and assess the effectiveness of such fire, making corrections where necessary. Fire control instruments The Coast Artillery's early fire control instruments supported optical rangefinding and position finding, either horizontal base or vertical base, with both systems usually present for each fort. Early horizontal base rangefinding required two azimuth (a.k.a. Bearing (navigation), bearing or Deflection (ballistics), deflection) instruments, preferably widely separated, and a communications system to transmit data to a plotting room and then to the guns. The instruments were often in bunkers called base end stations, as they defined the endpoints of a baseline. A base end station might ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
