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Boarding (attack)
Naval boarding action is an offensive tactic used in naval warfare to come up against (or alongside) an enemy marine vessel and attack by inserting combatants aboard that vessel. The goal of boarding is to invade and overrun the enemy personnel on board in order to capture, sabotage or destroy the enemy vessel. While boarding attacks were originally carried out by ordinary sailors who are proficient in hand-to-hand combat, larger warships often deploy specially trained and equipped regular troops such as marines and special forces as boarders. Boarding and close quarters combat had been a primary means to conclude a naval battle since antiquity, until the early modern period when heavy naval guns gained tactical primacy at sea. A cutting out boarding is an attack by small boats, preferably at night and against an unsuspecting, and anchored, target. It became popular in the later 18th century, and was extensively used during the Napoleonic Wars. This heralded the emphas ...
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Capture Of The Esmeralda (1820)
The capture of the frigate ''Esmeralda'' was a naval operation conducted on the nights of 5 and 6 November 1820. A division of boats with sailors and marines of the First Chilean Navy Squadron, commanded by Thomas Cochrane, stealthily advanced towards Callao and captured the ship through a boarding attack. was the flagship of Spanish fleet and the main objective of the operation.Fernández Duro 1903, p. 295. She was protected by a strong military defense that the royalists had organized in the port. Both Chilean and Spanish historiography considers that as a result of this naval action the importance or maritime influence of the Spanish Navy in the Pacific disappeared completely. British historians Brian Vale and David J. Cubitt follow the same line of opinion when affirming that Spain had unquestionably lost control of the sea against the Chilean Navy. Background On 20 August 1820, the Liberating Expedition commanded by General José de San Martín sailed from Valparaà ...
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Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in the Caribbean Sea. It has a territorial extension of , and its population was estimated at 29 million in 2022. The capital and largest urban agglomeration is the city of Caracas. The continental territory is bordered on the north by the Caribbean Sea and the Atlantic Ocean, on the west by Colombia, Brazil on the south, Trinidad and Tobago to the north-east and on the east by Guyana. The Venezuelan government maintains a claim against Guyana to Guayana Esequiba. Venezuela is a federal presidential republic consisting of 23 states, the Capital District and federal dependencies covering Venezuela's offshore islands. Venezuela is among the most urbanized countries in Latin America; the vast majority of Venezuelans live in the cities of th ...
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Air Ambulance
Air medical services is a comprehensive term covering the use of air transportation, aeroplane or helicopter, to move patients to and from healthcare facilities and accident scenes. Personnel provide comprehensive prehospital and emergency and critical care to all types of patients during aeromedical evacuation or rescue operations aboard helicopter and propeller aircraft or jet aircraft. The use of air transport to provide medical evacuation on the battlefield dates to World War I, but its role was expanded dramatically during the Korean and Vietnam wars. Later on, aircraft began to be used for the civilian emergency medical services. Helicopters can bring specialist care to the scene and transport patients to specialist hospitals, especially for major trauma cases. Fixed-wing aircraft are used for long-distance transport. In some remote areas, air medical services deliver non-emergency healthcare such as general practitioner appointments. An example of this is the Royal F ...
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Coast Guard
A coast guard or coastguard is a maritime security organization of a particular country. The term embraces wide range of responsibilities in different countries, from being a heavily armed military force with customs and security duties to being a volunteer organization tasked with search and rescue without law enforcement authority. In most countries, a typical coast guard's functions are distinct from those of the navy (a military service) and the transit police (a law enforcement agency), while in certain countries has similarities to both. History The predecessor of the United Kingdom's modern His Majesty's Coastguard was established in 1809 as the Waterguard, a department of the HM Customs and Excise authority, which was originally devoted to the prevention of smuggling. At the time, due to high UK taxation on liquors such as brandy, and on tobacco etc., smuggling of such cargoes from places such as France, Belgium, and Holland was an attractive proposition for ma ...
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Scuba Diving
Scuba diving is a mode of underwater diving whereby divers use breathing equipment that is completely independent of a surface air supply. The name "scuba", an acronym for " Self-Contained Underwater Breathing Apparatus", was coined by Christian J. Lambertsen in a patent submitted in 1952. Scuba divers carry their own source of breathing gas, usually compressed air, affording them greater independence and movement than surface-supplied divers, and more time underwater than free divers. Although the use of compressed air is common, a gas blend with a higher oxygen content, known as enriched air or nitrox, has become popular due to the reduced nitrogen intake during long and/or repetitive dives. Also, breathing gas diluted with helium may be used to reduce the likelihood and effects of nitrogen narcosis during deeper dives. Open circuit scuba systems discharge the breathing gas into the environment as it is exhaled, and consist of one or more diving cylinders containing br ...
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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 ...
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Submersibles
A submersible is a small watercraft designed to operate underwater. The term "submersible" is often used to differentiate from other underwater vessels known as submarines, in that a submarine is a fully self-sufficient craft, capable of independent cruising with its own power supply and air renewal system, whereas a submersible is usually supported by a nearby surface vessel, platform, shore team or sometimes a larger submarine. In common usage by the general public, however, the word "submarine" may be used to describe a craft that is by the technical definition actually a submersible. There are many types of submersibles, including both crewed and uncrewed craft, otherwise known as remotely operated vehicles (ROVs) or unmanned underwater vehicles (UUVs). Submersibles have many uses worldwide, such as oceanography, underwater archaeology, ocean exploration, adventure, equipment maintenance and recovery, and underwater videography. History The first underwater vessel was ...
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Codebook
A codebook is a type of document used for gathering and storing cryptography codes. Originally codebooks were often literally , but today codebook is a byword for the complete record of a series of codes, regardless of physical format. Cryptography In cryptography, a codebook is a document used for implementing a code. A codebook contains a lookup table for coding and decoding; each word or phrase has one or more strings which replace it. To decipher messages written in code, corresponding copies of the codebook must be available at either end. The distribution and physical security of codebooks presents a special difficulty in the use of codes, compared to the secret information used in ciphers, the key, which is typically much shorter. The United States National Security Agency documents sometimes use ''codebook'' to refer to block ciphers; compare their use of ''combiner-type algorithm'' to refer to stream ciphers. Codebook come in two forms, one-part or two-part: * In o ...
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Cipher
In cryptography, a cipher (or cypher) is an algorithm for performing encryption or decryption—a series of well-defined steps that can be followed as a procedure. An alternative, less common term is ''encipherment''. To encipher or encode is to convert information into cipher or code. In common parlance, "cipher" is synonymous with "code", as they are both a set of steps that encrypt a message; however, the concepts are distinct in cryptography, especially classical cryptography. Codes generally substitute different length strings of characters in the output, while ciphers generally substitute the same number of characters as are input. There are exceptions and some cipher systems may use slightly more, or fewer, characters when output versus the number that were input. Codes operated by substituting according to a large codebook which linked a random string of characters or numbers to a word or phrase. For example, "UQJHSE" could be the code for "Proceed to the followi ...
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Naval Intelligence
Military intelligence is a military discipline that uses information collection and analysis approaches to provide guidance and direction to assist commanders in their decisions. This aim is achieved by providing an assessment of data from a range of sources, directed towards the commanders' mission requirements or responding to questions as part of operational or campaign planning. To provide an analysis, the commander's information requirements are first identified, which are then incorporated into intelligence collection, analysis, and dissemination. Areas of study may include the operational environment, hostile, friendly and neutral forces, the civilian population in an area of combat operations, and other broader areas of interest. Intelligence activities are conducted at all levels, from tactical to strategic, in peacetime, the period of transition to war, and during a war itself. Most governments maintain a military intelligence capability to provide analytical and i ...
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Military Helicopter
A military helicopter is a helicopter that is either specifically built or converted for use by military forces. A military helicopter's mission is a function of its design or conversion. The most common use of military helicopters is transport of troops, but transport helicopters can be modified or converted to perform other missions such as combat search and rescue (CSAR), medical evacuation (MEDEVAC), airborne command post, or even armed with weapons for attacking ground targets. Specialized military helicopters are intended to conduct specific missions. Examples of specialized military helicopters are attack helicopters, observation helicopters and anti-submarine warfare helicopters. Types and roles Military helicopters play an integral part in the sea, land and air operations of modern militaries. Generally manufacturers will develop airframes in different weight/size classes which can be adapted to different roles through the installation of mission specific equipmen ...
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Frogman
A frogman is someone who is trained in scuba diving or swimming underwater in a tactical capacity that includes military, and in some European countries, police work. Such personnel are also known by the more formal names of combat diver, combatant diver, or combat swimmer. The word ''frogman'' first arose in the stage name ''The Fearless Frogman'' of Paul Boyton in the 1870s and later was claimed by John Spence, an enlisted member of the U.S. Navy and member of the OSS Maritime Unit, to have been applied to him while he was training in a green waterproof suit. The term ''frogman'' is occasionally used to refer to a civilian scuba diver. Some sport diving clubs include the word ''Frogmen'' in their names. The preferred term by scuba users is ''diver'', but the ''frogman'' epithet persists in informal usage by non-divers, especially in the media and often referring to professional scuba divers, such as in a police diving role. In the U.S. military and intelligence commun ...
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