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Anti-submarine
An anti-submarine weapon (ASW) is any one of a number of devices that are intended to act against a submarine and its crew, to destroy (sink) the vessel or reduce its capability as a weapon of war. In its simplest sense, an anti-submarine weapon is usually a projectile, missile or bomb that is optimized to destroy submarines. History Before World War I Prior to about 1890, naval weapons were only used against surface shipping. With the rise of the military submarine after this time, countermeasures were considered for use against them. The first submarine installation of torpedo tubes was in 1885 and the first ship was sunk by a submarine-launched torpedo in 1887. There were only two ways of countering the military submarine initially: ramming them or sinking them with gunfire. However, once they were submerged, they were largely immune until they had to surface again. By the start of the First World War there were nearly 300 submarines in service with another 80 in production. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-submarine Warfare
Anti-submarine warfare (ASW, or in the older form A/S) is a branch of underwater warfare that uses surface warships, aircraft, submarines, or other platforms, to find, track, and deter, damage, or destroy enemy submarines. Such operations are typically carried out to protect friendly shipping and coastal facilities from submarine attacks and to overcome blockades. Successful ASW operations typically involve a combination of sensor and weapon technologies, along with effective deployment strategies and sufficiently trained personnel. Typically, sophisticated sonar equipment is used for first detecting, then classifying, locating, and tracking a target submarine. Sensors are therefore a key element of ASW. Common weapons for attacking submarines include torpedoes and naval mines, which can both be launched from an array of air, surface, and underwater platforms. ASW capabilities are often considered of significant strategic importance, particularly following provocative instanc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battle Of The Atlantic
The Battle of the Atlantic, the longest continuous military campaign in World War II, ran from 1939 to the defeat of Nazi Germany in 1945, covering a major part of the naval history of World War II. At its core was the Allies of World War II, Allied naval Blockade of Germany (1939–1945), blockade of Germany, announced the day after the declaration of war, and Germany's subsequent counter-blockade. The campaign peaked from mid-1940 to the end of 1943. The Battle of the Atlantic pitted U-boats and other warships of the German (navy) and aircraft of the (air force) against the Royal Navy, Royal Canadian Navy, United States Navy, and Merchant Navy (United Kingdom), Allied merchant shipping. Convoys, coming mainly from North America and predominantly going to the United Kingdom and the Soviet Union, were protected for the most part by the British and Canadian navies and air forces. These forces were aided by ships and aircraft of the United States beginning on 13 September 1941. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depth Charge
A depth charge is an anti-submarine warfare (ASW) weapon designed to destroy submarine A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...s by detonating in the water near the target and subjecting it to a destructive shock factor, hydraulic shock. Most depth charges use high explosives with a fuze set to detonate the charge, typically at a specific depth from the surface. Depth charges can be dropped by ships (typically fast, agile surface combatants such as destroyers or frigates), patrol aircraft and helicopters. Depth charges were developed during World War I, and were one of the first viable methods of attacking a submarine underwater. They were widely used in World War I and World War II, and remained part of the anti-submarine arsenals of many navies during the Cold War, duri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels. "Sonar" can refer to one of two types of technology: ''passive'' sonar means listening for the sound made by vessels; ''active'' sonar means emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used for robot navigation, and sodar (an upward-looking in-air sonar) is used for atmospheric investigations. The term ''sonar'' is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low (infrasonic) to extrem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leigh Light
The Leigh Light (L/L) was a British World War II era anti-submarine device used in the Battle of the Atlantic. It was a powerful (22 million candelas) carbon arc searchlight of diameter fitted to a number of the British Royal Air Force's Coastal Command patrol bombers to help them spot surfaced German U-boats at night. Early night operations with the new air-to-surface-vessel (ASV) radar demonstrated that the radar's minimum range of about meant that the target was still invisible when it disappeared off the radar display. Efforts to reduce this minimum were not successful, so Wing Commander Humphrey de Verd Leigh hit upon the idea of using a searchlight that would be switched on just when the target was about to disappear on radar. The U-boat had insufficient time to dive and the bombardier had a clear view of the target. Introduced in June 1942, it was so successful that for a time German submarines were forced to switch to charging their batteries during the day ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submarine
A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or informally to refer to remotely operated vehicles and Autonomous underwater vehicle, robots, or to medium-sized or smaller vessels (such as the midget submarine and the wet sub). Submarines are referred to as ''boats'' rather than ''ships'' regardless of their size. Although experimental submarines had been built earlier, submarine design took off during the 19th century, and submarines were adopted by several navies. They were first used widely during World War I (1914–1918), and are now used in many navy, navies, large and small. Their military uses include: attacking enemy surface ships (merchant and military) or other submarines; aircraft carrier protection; Blockade runner, blockade running; Ballistic missile submarine, nuclear deterrenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hedgehog (weapon)
The Hedgehog (also known as an ''Anti-Submarine Projector'') was a forward-throwing anti-submarine weapon that was used primarily during the Second World War. The device, which was developed by the Royal Navy, fired up to 24 spigot mortars ahead of a ship when attacking a U-boat. It was deployed on convoy escort warships such as destroyers and corvettes to supplement the depth charges. As the mortar projectiles employed contact fuzes rather than time or bathymetric (depth) fuzes, detonation occurred directly against a hard surface such as the hull of a submarine making it more deadly than depth charges, which relied on damage caused by hydrostatic shockwaves. During World War II out of 5,174 British depth charge attacks there were 85.5 kills, a ratio of 60.5 to 1. In comparison, the Hedgehog made 268 attacks for 47 kills, a ratio of 5.7 to 1. Development The "Hedgehog", so named because the empty rows of its launcher spigots resembled the spines on the back of a hedgeh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convoy
A convoy is a group of vehicles, typically motor vehicles or ships, traveling together for mutual support and protection. Often, a convoy is organized with armed defensive support and can help maintain cohesion within a unit. It may also be used in a non-military sense, for example when driving through remote areas. Naval convoys Age of Sail Naval convoys have been in use for centuries, with examples of merchant ships traveling under naval protection dating to the 12th century. The use of organized naval convoys dates from when ships began to be separated into specialist classes and national navies were established. By the French Revolutionary Wars of the late 18th century, effective naval convoy tactics had been developed to ward off pirates and privateers. Some convoys contained several hundred merchant ships. The most enduring system of convoys were the Spanish treasure fleets, that sailed from the 1520s until 1790. When merchant ships sailed independently, a privateer c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
U-boat
U-boats are Submarine#Military, naval submarines operated by Germany, including during the World War I, First and Second World Wars. The term is an Anglicization#Loanwords, anglicized form of the German word , a shortening of (), though the German term refers to any submarine. Austro-Hungarian Navy submarines were also known as U-boats. U-boats are most known for their unrestricted submarine warfare in both world wars, trying to Commerce raiding, disrupt merchant traffic towards the UK and force the UK out of the war. In World War I, Germany intermittently waged unrestricted submarine warfare against the United Kingdom, UK: a first campaign in 1915 was abandoned after strong protests from the US but in 1917 the Germans, facing deadlock on the continent, saw no other option than to resume the campaign in February 1917. The renewed campaign failed to achieve its goal mainly because of the introduction of Convoys in World War I, convoys. Instead the campaign ensured final defeat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Q-ship
Q-ships, also known as Q-boats, decoy vessels, special service ships, or mystery ships, were heavily armed merchantman, armed merchant ships with concealed weaponry, designed to lure submarines into making surface attacks. This gave Q-ships the chance to open fire and sink them. They were used by the United Kingdom, British Royal Navy and the German Imperial German Navy, ''Kaiserliche Marine'' during the World War I, First World War and by the Royal Navy, the ''Kriegsmarine'', the Imperial Japanese Navy, and the United States Navy during the World War II, Second World War. Though legally recognised as an acceptable tactic of military deception, they have attracted much controversy, enjoying only marginal success during WWI and none in WWII. Etymology Short for Cobh, Queenstown in Ireland, as Haulbowline Dockyard in Cork Harbour was responsible for the conversion of many mercantile steamers to armed decoy ships in World War One, although the majority appear to have been converted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrophone
A hydrophone () is a microphone designed for underwater use, for recording or listening to underwater sound. Most hydrophones contains a piezoelectric transducer that generates an electric potential when subjected to a pressure change, such as a sound wave. A hydrophone can also detect airborne sounds but is insensitive of them because it is designed to match the acoustic impedance of water, a denser fluid than air. Sound travels 4.3 times faster in water than in air, and a sound wave in water exerts a pressure 60 times more than what is exerted by a wave of the same amplitude in air. Similarly, a standard microphone can be buried in the ground, or immersed in water if it is put in a waterproof container but will give poor performance because of the similarly-bad acoustic impedance match. History The first hydrophones consisted of a tube with a thin membrane covering the submerged end and the observer's ear of the equipment. The design of effective hydrophones must take into a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
