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Dora (artillery)
Schwerer Gustav (English: ''Heavy Gustav'') was a German railway gun. It was developed in the late 1930s by Krupp in Rügenwalde as list of siege artillery, siege artillery for the explicit purpose of destroying the main forts of the French Maginot Line, the strongest fortifications in existence at the time. The fully assembled gun weighed nearly and could fire shells weighing to a range of . The gun was designed in preparation for the Battle of France but was not ready for action when that battle began, and the Wehrmacht offensive through Belgium rapidly outflanked and isolated the Maginot Line, which was then besieged with more conventional heavy guns until Armistice of 22 June 1940, French capitulation. Gustav was later deployed in the Soviet Union during the Battle of Sevastopol, part of Operation Barbarossa, where, among other things, it destroyed a munition depot located roughly below sea level. The gun was moved to Leningrad, and may have been intended to be used in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nazi Germany
Nazi Germany, officially known as the German Reich and later the Greater German Reich, was the German Reich, German state between 1933 and 1945, when Adolf Hitler and the Nazi Party controlled the country, transforming it into a Totalitarianism, totalitarian dictatorship. The Third Reich, meaning "Third Realm" or "Third Empire", referred to the Nazi claim that Nazi Germany was the successor to the earlier Holy Roman Empire (800–1806) and German Empire (1871–1918). The Third Reich, which the Nazis referred to as the Thousand-Year Reich, ended in May 1945, after 12 years, when the Allies of World War II, Allies defeated Germany and entered the capital, Berlin, End of World War II in Europe, ending World War II in Europe. After Hitler was appointed Chancellor of Germany in 1933, the Nazi Party began to eliminate political opposition and consolidate power. A 1934 German referendum confirmed Hitler as sole ''Führer'' (leader). Power was centralised in Hitler's person, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battle Of Sevastopol
A battle is an occurrence of combat in warfare between opposing military units of any number or size. A war usually consists of multiple battles. In general, a battle is a military engagement that is well defined in duration, area, and force commitment. An engagement with only limited commitment between the forces and without decisive results is sometimes called a skirmish. The word "battle" can also be used infrequently to refer to an entire operational campaign, although this usage greatly diverges from its conventional or customary meaning. Generally, the word "battle" is used for such campaigns if referring to a protracted combat encounter in which either one or both of the combatants had the same methods, resources, and strategic objectives throughout the encounter. Some prominent examples of this would be the Battle of the Atlantic, Battle of Britain, and the Battle of France, all in World War II. Wars and military campaigns are guided by military strategy, whereas batt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crane (rail)
A railway crane (North America: railroad crane, crane car or wrecker; UK: breakdown crane) is a type of Crane (machine), crane used on a rail transport, railway for one of three primary purposes: freight handling in goods yards, maintenance of way, permanent way (PW) maintenance, and accident recovery work. Although the design differs according to the type of work, the basic configuration is similar in all cases: a rotating crane body is mounted on a sturdy chassis fitted with flanged wheels. The body supports the jib (UK; North America: Crane (machine), boom) and provides all the lifting and operating mechanisms; on larger cranes, an operator's cabin is usually provided. The chassis is fitted with buffing (UK) and/or coupling gear to allow the crane to be moved by a locomotive, although many are also self-propelled to allow limited movement about a work site. For cranes with a jib that extends beyond the length of the chassis, an Flatcar#Idler flatcars, idler car (also known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Locomotives
A locomotive is a rail vehicle that provides the motive power for a train. Traditionally, locomotives pulled trains from the front. However, push–pull operation has become common, and in the pursuit for longer and heavier freight trains, companies are increasingly using distributed power: single or multiple locomotives placed at the front and rear and at intermediate points throughout the train under the control of the leading locomotive. Etymology The word ''locomotive'' originates from the Latin 'from a place', ablative of 'place', and the Medieval Latin 'causing motion', and is a shortened form of the term ''locomotive engine'', which was first used in 1814 to distinguish between self-propelled and stationary steam engines. Classifications Prior to locomotives, the motive force for railways had been generated by various lower-technology methods such as human power, horse power, gravity or stationary engines that drove cable systems. Few such systems are sti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reinforced Concrete
Reinforced concrete, also called ferroconcrete or ferro-concrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is usually, though not necessarily, steel reinforcing bars (known as rebar) and is usually embedded passively in the concrete before the concrete sets. However, post-tensioning is also employed as a technique to reinforce the concrete. In terms of volume used annually, it is one of the most common engineering materials. In corrosion engineering terms, when designed correctly, the alkalinity of the concrete protects the steel rebar from corrosion. Description Reinforcing schemes are generally designed to resist tensile stresses in particular regions of the concrete that might cause unacceptable cracking and/or structural failure. Modern reinforced concrete can contain varied reinforcing materials made o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Essen
Essen () is the central and, after Dortmund, second-largest city of the Ruhr, the largest urban area in Germany. Its population of makes it the fourth-largest city of North Rhine-Westphalia after Cologne, Düsseldorf and Dortmund, as well as the List of cities in Germany by population, tenth-largest city of Germany. Essen lies in the larger Rhine-Ruhr metropolitan region, List of EU metropolitan regions by GDP#2021 ranking of top 4 German metropolitan regions, second largest by GDP in the EU, and is part of the cultural area of Rhineland. Because of its central location in the Ruhr, Essen is often regarded as the Ruhr's "secret capital". Two rivers flow through the city: the Emscher in the north, and in the south the Ruhr (river), Ruhr River, which is dammed in Essen to form the and reservoirs. The central and northern boroughs of Essen historically belong to the Low German Westphalian dialects area, and the south of the city to the Low Franconian Bergish dialects, Bergish ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oberkommando Des Heeres
The (; abbreviated OKH) was the high command of the Army of Nazi Germany. It was founded in 1935 as part of Adolf Hitler's rearmament of Germany. OKH was ''de facto'' the most important unit within the German war planning until the defeat at Moscow in December 1941. During World War II, OKH had the responsibility of strategic planning of Armies and Army Groups. The General Staff of the OKH managed operational matters. Each German Army also had an Army High Command ( or AOK). The Armed Forces High Command () then took over this function for theatres other than the Eastern front. The OKH commander held the title of Commander-in-chief of the Army (). After the Battle of Moscow, the OKH commander Field marshal Walther von Brauchitsch was removed from office, and Hitler appointed himself as Commander-in-Chief of the Army. From 1938, OKH was, together with () and () formally subordinated to the . OKH vs OKW OKH had been independent until February 1938, when Hitler creat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Little David
Little David was the nickname of an American caliber mortar designed to breach the Siegfried Line and then used for test-firing aerial bombs during World War II. With the same calibre as the British Mallet's Mortar, constructed in May 1857, it is one of the largest-calibre guns ever built, having a larger calibre than both of Germany's Schwerer Gustav and Dora which were railway guns. History The mortar was developed as an extension of a previous proposal to destroy heavy concrete fortifications such as the Siegfried Line with massive plastic explosive charges delivered by rocket or bomb. During a discussion between representatives of the Ballistic Research Laboratory and the Office of the Chief of Ordnance it was suggested that instead of dropping such a charge from an airplane, it could be fired from a mortar. Development began of a siege mortar firing a shell. The mortar's base was a large steel box that was placed below ground, with its top flush with the surrounding s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mallet's Mortar
Mallet's Mortar was a 19th-century British Shell (projectile), shell-firing Mortar (weapons), mortar built for the Crimean War, but never used in combat. The mortar was designed by Robert Mallet and was constructed in sections so that it could be more easily transported. Mallet first made his design public in 1854. There was little response from the government until Mallet wrote to the Prime Minister Henry John Temple, 3rd Viscount Palmerston, Lord Palmerston in March 1855. Palmerston was taken with the idea and instructed the Board of Ordnance to arrange for the construction of two mortars of Mallet's design. Thames Ironworks and Shipbuilding Company won the contract at a price of £4,300 per mortar. The company's bankruptcy resulted in the work being divided among three firms which managed to deliver the mortars in May 1857. Testing began on 19 October 1857 with further testing taking place on 18 December 1857, 21 July 1858, and 28 July 1858. Each test was brought to an end by d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caliber
In guns, particularly firearms, but not #As a measurement of length, artillery, where a different definition may apply, caliber (or calibre; sometimes abbreviated as "cal") is the specified nominal internal diameter of the gun barrel Gauge (firearms), bore – regardless of how or where the bore is measured and whether the finished bore matches that specification. It is measured in inches or in millimetres, millimeters]ref name=barnes2016-p9> In the United States it is expressed in hundredths of an inch; in the United Kingdom in thousandths; and elsewhere in millimeters. For example, a US "45 caliber" firearm has a barrel diameter of roughly 0.45 inches (11.43mm). Barrel diameters can also be expressed using metric dimensions. For example, a "9 mm pistol" has a barrel diameter of about 9 millimeters. Since metric and US customary units do not convert evenly at this scale, metric conversions of caliber measured in decimal inches are typically approximations of the precise spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rifling
Rifling is the term for helical grooves machined into the internal surface of a firearms's barrel for imparting a spin to a projectile to improve its aerodynamic stability and accuracy. It is also the term (as a verb) for creating such grooves. The opposite of rifling is smoothbore. Rifling is measured in ''twist rate'', the distance the rifling takes to complete one full revolution, expressed as a ratio with 1 as its base (e.g., 1:). A shorter distance/lower ratio indicates a faster twist, generating a higher spin rate (and greater projectile stability). The combination of length, weight, and shape of a projectile determines the twist rate needed to gyroscopically stabilize it: barrels intended for short, large-diameter projectiles such as spherical lead balls require a very low twist rate, such as 1 turn in 48 inches (122 cm). Barrels intended for long, small-diameter projectiles, such as the ultra-low-drag 80-grain 0.223 inch bullets (5.2 g, 5.56&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
