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Pathfinder (RAF)
The Pathfinders were target-marking Squadron (aviation), squadrons in RAF Bomber Command during World War II. They located and marked targets with flares, at which a main bomber force could aim, increasing the accuracy of their bombing. The Pathfinders were normally the first to receive new blind-bombing aids such as Gee (navigation), Gee, Oboe (navigation), Oboe and the H2S radar. The early Pathfinder Force (PFF) squadrons were expanded to become a group, No. 8 Group RAF, No. 8 (Pathfinder Force) Group, in January 1943. The initial Pathfinder Force was five squadrons, whilst No 8 Group ultimately grew to a strength of 19 squadrons. Whereas the majority of Pathfinder squadrons and personnel were from the Royal Air Force, the group also included No 405 Squadron of the Royal Canadian Air Force as well as many individual airmen from the air forces of other Commonwealth of Nations, Commonwealth countries. History Background At the start of the Second World War in September 1939 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathfinder (USAAF)
The 482d Operations Group is a United States Air Force Reserve unit assigned to the 482d Fighter Wing. It is stationed at Homestead Air Reserve Base, Florida. During World War II, the group was activated in England as the 482d Bombardment Group (Pathfinder), the only Eighth Air Force radar-equipped pathfinder heavy bomber group. Its Boeing B-17 Flying Fortress and Consolidated B-24 Liberator aircraft were equipped with first generation radars to guide other bombardment groups to targets obscured by cloud cover over Occupied Europe and Nazi Germany, earning a Distinguished Unit Citation. In 1944, it was removed from combat to focus on training pathfinder aircrews and develop tactics, although its developmental work occasionally required it to fly combat missions. After V-E Day, the group returned to the United States and was inactivated. The group became a military reserve force, reserve organization, serving as a bombardment unit from 1947-1949 and briefly as an airlift unit i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Billy Strachan's Flying Helmet And Goggles
Billy may refer to: * Billy (name), a name (and list of people with the name) * Billy (surname), a surname (and list of people with the surname) Animals * Billy (dog), a dog breed * Billy (pigeon), awarded the Dickin Medal in 1945 * Billy (pygmy hippo), a pet of U.S. President Calvin Coolidge * Billy, a young male domestic goat Film * Billy (''Black Christmas''), a character from ''Black Christmas'' * Billy (''Saw''), a puppet from ''Saw'' * '' Billy: The Early Years'', a 2008 biographical film about Billy Graham Literature * ''Billy'' (novel), a 1990 novel by Whitley Strieber * ''Billy'', a 2002 biography of Billy Connolly by Pamela Stephenson Music Musicals * ''Billy'' (musical), a musical based on Billy Liar * ''Billy'', a 1969 Broadway musical with music and lyrics by Gene Allen and Ron Dante Albums * ''Billy'' (Samiam album) (1992) * ''Billy'' (Feedtime album) Songs * "Billy" (Kathy Linden song), a 1958 song by Kathy Linden * "Billy", a 1986 song by C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruhr
The Ruhr ( ; , also ''Ruhrpott'' ), also referred to as the Ruhr Area, sometimes Ruhr District, Ruhr Region, or Ruhr Valley, is a polycentric urban area in North Rhine-Westphalia, Germany. With a population density of 1,160/km2 and a population of over 5 million (2017), it is the largest urban area in Germany and the third of the European Union. It consists of several large cities bordered by the rivers Ruhr to the south, Rhine to the west, and Lippe to the north. In the southwest it borders the Bergisches Land. It is considered part of the larger Rhine-Ruhr metropolitan region of more than 10 million people, which is the third largest in Western Europe, behind only London and Paris. The Ruhr cities are, from west to east: Duisburg, Oberhausen, Bottrop, Mülheim an der Ruhr, Essen, Gelsenkirchen, Bochum, Herne, Hagen, Dortmund, Hamm and the districts of Wesel, Recklinghausen, Unna and Ennepe-Ruhr-Kreis. The most populous cities are Dortmund (with a population of app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Course Setting Bomb Sight
The Course Setting Bomb Sight (CSBS) is the canonical ''vector'' bombsight, the first practical system for properly accounting for the effects of wind when dropping bombs. It is also widely referred to as the Wimperis sight after its inventor, Harry Wimperis. The CSBS was developed for the Royal Naval Air Service (RNAS) in order to attack submarines and ships. It was introduced in 1917, and was such a great advance over earlier designs that it was quickly adopted by the Royal Flying Corps, and the Independent Air Force. It has been called "the most important bomb sight of the war". After the war the design found widespread use around the world. A US version of the CSBS was used by Billy Mitchell on his famous attack on the SMS Ostfriesland, ''Ostfriesland'' in SMS Ostfriesland#US bombing target, 1921. The basic design was adapted by almost all air forces and used well into World War II. It was eventually replaced in British service by more advanced designs like the Mark XIV bomb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dead Reckoning
In navigation, dead reckoning is the process of calculating the current position of a moving object by using a previously determined position, or fix, and incorporating estimates of speed, heading (or direction or course), and elapsed time. The corresponding term in biology, to describe the processes by which animals update their estimates of position or heading, is path integration. Advances in navigational aids that give accurate information on position, in particular satellite navigation using the Global Positioning System, have made simple dead reckoning by humans obsolete for most purposes. However, inertial navigation systems, which provide very accurate directional information, use dead reckoning and are very widely applied. Etymology Contrary to myth, the term "dead reckoning" was not originally used to abbreviate "deduced reckoning", nor is it a misspelling of the term "ded reckoning". The use of "ded" or "deduced reckoning" is not known to have appeared earlier th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Navigation
Radio navigation or radionavigation is the application of radio waves to geolocalization, determine a position of an object on the Earth, either the vessel or an obstruction. Like radiolocation, it is a type of Radiodetermination-satellite service, radiodetermination. The basic principles are measurements from/to electric beacons, especially * Direction (geometry), Angular directions, e.g. by bearing, radio phases or interferometry, * Distance measuring equipment, Distances, e.g. ranging by measurement of time of flight between one transmitter and multiple receivers or vice versa, * Distance ''differences'' by measurement of multilateration, times of arrival of signals from one transmitter to multiple receivers or vice versa * Partly also velocity, e.g. by means of radio Doppler shift. Combinations of these measurement principles also are important—e.g., many radars measure range and azimuth of a target. Bearing-measurement systems These systems used some form of directional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Searchlight
A searchlight (or spotlight) is an apparatus that combines an extremely luminosity, bright source (traditionally a carbon arc lamp) with a mirrored parabolic reflector to project a powerful beam of light of approximately parallel rays in a particular direction. It is usually constructed so that it can be swiveled about. The most common element used in modern searchlights is Xenon, Xenon (Xe). However, Rare-earth elements such as lanthanum, lanthanum (La) and cerium, cerium (Ce) are used in phosphors to improve light quality in some specialized searchlights. Military use The first use of searchlights using carbon arc technology occurred during the Siege of Paris (1870-71), Siege of Paris during the Franco-Prussian War. The Royal Navy used searchlights in 1882 to dazzle and prevent Egyptian forces from manning artillery batteries at Bombardment of Alexandria, Alexandria. Later that same year, the French and British forces landed troops under searchlights. By 1907 the value o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freya Radar
Freya was an early warning radar deployed by Germany during World War II; it was named after the Norse goddess Freyja. During the war, over a thousand stations were built. A naval version operating on a slightly different wavelength was also developed as the ''Seetakt''. Development First tests of what would become the "''Freya''" were conducted in early 1937, with initial delivery of an operational radar to the ''Kriegsmarine'' in 1938 by the GEMA company. Freya supported an early version of Identification friend or foe (IFF). Aircraft equipped with the FuG 25a "''Erstling''" IFF system could be successfully queried across ranges of over 100 km. The "AN" version gained a switchable phasing line for the antenna. Switching in the phasing line led to a phase displacement of the antenna's radiation pattern and with that, a squinting to the left or right. This enabled the system in effect to switch from the rather broad "scanning for maxima" to narrow lobe switching ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heligoland Bight
The Heligoland Bight, also known as Helgoland Bight, (, ) is a bay which forms the southern part of the German Bight, itself a bay of the North Sea, located at the mouth of the Elbe river. The Heligoland Bight extends from the mouth of the Elbe to the islands of Heligoland and lies between the East Frisian island of Wangerooge and the North Frisian peninsula of Eiderstedt. The bight is named after Heligoland. It was the location of World War I naval battles in 1914 and 1917. In 1939 it also had a World War II aerial battle named after it. In the Heligoland Basin (''Helgoländer Becken''), a basin lying directly southwest of Heligoland, the bight is up to deep. One of the busiest shipping lanes in the world, from Hamburg and the mouth of the Elbe to the Straits of Dover and the English Channel, runs through the Heligoland Bight. The area also includes nature reserves such as the ''Heligoland Felssockel'' and the protected Wadden Sea, in which the Wadden Sea National P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vickers Wellington
The Vickers Wellington (nicknamed the Wimpy) is a British twin-engined, long-range medium bomber. It was designed during the mid-1930s at Brooklands in Weybridge, Surrey. Led by Vickers-Armstrongs' chief designer Rex Pierson, a key feature of the aircraft is its geodetic airframe fuselage structure, which was principally designed by Barnes Wallis. Development had been started in response to Air Ministry List Of Air Ministry Specifications, Specification B.9/32, issued in the middle of 1932, for a bomber for the Royal Air Force. This specification called for a twin-engined day bomber capable of delivering higher performance than any previous design. Other aircraft developed to the same specification include the Armstrong Whitworth Whitley and the Handley Page Hampden. During the development process, performance requirements such as for the tare weight changed substantially, and the engine used was not the one originally intended. Despite the original specification, the Wellingto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain. The term ''RADAR'' was coined in 1940 by the United States Navy as an acronym for "radio detection and ranging". The term ''radar'' has since entered English and other languages as an anacronym, a common noun, losing all capitalization. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
