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IFF Mark III
IFF Mark III, also known as ARI.5025 in the UK or SCR.595 in the US, was the Allied Forces standard identification friend or foe (IFF) system from 1943 until well after the end of World War II. It was widely used by aircraft, ships, and submarines, as well as in various adaptations for secondary purposes like search and rescue. 500 units were also supplied to the Soviet Union during the war. Mark III replaced the earlier Mark II which had been in service since 1940. Mark II had an antenna that received signals from radar systems, amplified them, and returned them. This caused the ''blip'' on the radar display to become larger, indicating a friendly aircraft. As the number of radar systems on different frequencies proliferated through the mid-war period, the number of models of Mark II had to do the same. Aircraft could never be sure their IFF would respond to the radars they flew over. Freddie Williams had suggested using a single separate frequency for IFF as early as 1940, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Supermarine Spitfire Mk IXE Of No
A, or a, is the first letter and the first vowel letter of the Latin alphabet, used in the modern English alphabet, and others worldwide. Its name in English is '' a'' (pronounced ), plural ''aes''. It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version is often written in one of two forms: the double-storey and single-storey . The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English, '' a'' is the indefinite article, with the alternative form ''an''. Name In English, the name of the letter is the ''long A'' sound, pronounced . Its name in most other languages matches the letter's pronunciation in open syllables. History The earliest known ancestor of A is ''aleph''—the first letter of the Phoenician ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Display
A radar display is an electronic device that presents radar data to the operator. The radar system transmits pulses or continuous waves of electromagnetic radiation, a small portion of which backscatter off targets (intended or otherwise) and return to the radar system. The receiver converts all received electromagnetic radiation into a continuous electronic analog signal of varying (or oscillating) voltage that can be converted then to a screen display. Modern systems typically use some sort of raster graphics, raster scan display to produce a map-like image. Early in radar development, however, numerous circumstances made such displays difficult to produce. People developed several different display types. Oscilloscopes Early radar displays used adapted oscilloscopes with various inputs. An oscilloscope generally receives three ''channels'' of varying (or oscillating) voltage as input and displays this information on a cathode ray tube. The oscilloscope amplifies the input vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hugh Dowding
Air Chief Marshal Hugh Caswall Tremenheere Dowding, 1st Baron Dowding, (24 April 1882 – 15 February 1970) was a senior officer in the Royal Air Force. He was Air Officer Commanding RAF Fighter Command during the Battle of Britain and is generally credited with playing a crucial role in Britain's defence, and hence, the defeat of Operation Sea Lion, Adolf Hitler's plan to invade Britain. Born in Moffat, Scotland, Dowding was an officer in the British Army in the 1900s and early 1910s. He joined the Royal Flying Corps at the start of the First World War and went on to serve as a fighter pilot and then as commanding officer of No. 16 Squadron. During the inter-war years he became Air Officer Commanding Fighting Area, Air Defence of Great Britain and then joined the Air Council as Air Member for Supply and Research. In July 1936, Dowding was appointed chief of the newly created RAF Fighter Command. During the Battle of Britain in the Second World War, Dowding's Fighter Command ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
255 Squadron RAF Beaufighter MK II At RAF Hibaldstow Sept 1941
55 may refer to: *55 (number) *55 BC * AD 55 *1955 *2055 Science *Caesium, by the element's atomic number Astronomy *Messier object M55, a magnitude 7.0 globular cluster in the constellation Sagittarius *The New General Catalogue object NGC 55, a magnitude 7.9 barred spiral galaxy in the constellation Sculptor * 55 Nights, mixtape by british rapper Future Transportation *The highest speed limit allowed in the United States between 1974 and 1986 per the National Maximum Speed Law *Highway 55, several roads *Route 55 (other), bus and tram routes *DAF 55, a small family car Film *''55 Days at Peking'', a film starring Charlton Heston and David Niven Other uses *''Gazeta 55'', an Albanian newspaper *Agitation and Propaganda against the State, also known as Constitution law 55, a law during Communist Albania * +55, the code for international direct dial phone calls to Brazil *5:5, law enforcement code for handcuffs * ''55'' (album), by the Knocks *"55", a 2022 song by Ray ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering carrier-based aircraft, shipborne aircraft. Typically it is the capital ship of a naval fleet, fleet (known as a carrier battle group), as it allows a naval force to power projection, project seaborne naval aviation, air power far from homeland without depending on local airfields for staging area, staging aerial warfare, aircraft operations. Since their inception in the early 20th century, aircraft carriers have evolved from wooden vessels used to deploy individual tethered reconnaissance balloons, to nuclear marine propulsion, nuclear-powered supercarriers that carry dozens of fighter aircraft, fighters, strike aircraft, military helicopters, airborne early warning and control, AEW&Cs and other types of aircraft such as unmanned combat aerial vehicle, UCAVs. While heavier fixed-wing aircraft such as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathode Ray Tube
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms on an oscilloscope, a Film frame, frame of video on an Analog television, analog television set (TV), Digital imaging, digital raster graphics on a computer monitor, or other phenomena like radar targets. A CRT in a TV is commonly called a picture tube. CRTs have also been Williams tube, used as memory devices, in which case the screen is not intended to be visible to an observer. The term ''cathode ray'' was used to describe electron beams when they were first discovered, before it was understood that what was emitted from the cathode was a beam of electrons. In CRT TVs and computer monitors, the entire front area of the tube is scanned repeatedly and systematically in a fixed pattern called a raster scan, raster. In color devices, an image is produced by con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unipole
The folded unipole antenna is a type of monopole mast radiator antenna used as a transmitting antenna mainly in the medium wave band for AM radio broadcasting stations. It consists of a vertical metal rod or mast mounted over and connected at its base to a grounding system consisting of buried wires. The mast is surrounded by a "skirt" of vertical wires electrically attached at or near the top of the mast. The skirt wires are connected by a metal ring near the mast base, and the feedline feeding power from the transmitter is connected between the ring and the ground. It has seen much use for refurbishing medium wave AM broadcasting station towers in the United States and other countries. When an AM radio station shares a tower with other antennas such as FM broadcasting antennas, the folded unipole is often a good choice. Since the base of the tower connects to the ground system, unlike in an ordinary mast radiator tower in which the base is at high voltage, the transmission li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supermarine Spitfire
The Supermarine Spitfire is a British single-seat fighter aircraft that was used by the Royal Air Force and other Allies of World War II, Allied countries before, during, and after World War II. It was the only British fighter produced continuously throughout the war. The Spitfire remains popular among enthusiasts. Around List of surviving Supermarine Spitfires, 70 remain airworthy, and many more are static exhibits in aviation museums throughout the world. The Spitfire was a short-range, high-performance interceptor aircraft designed by R. J. Mitchell, chief designer at Supermarine Aviation Works, which operated as a subsidiary of Vickers-Armstrong from 1928. Mitchell modified the Spitfire's distinctive elliptical wing (designed by Beverley Shenstone) with innovative sunken rivets to have the thinnest possible cross-section, achieving a potential top speed greater than that of several contemporary fighter aircraft, including the Hawker Hurricane. Mitchell continued to refine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horizontally Polarized
, or , is a property of transverse waves which specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave. One example of a polarized transverse wave is vibrations traveling along a taut string, for example, in a musical instrument like a guitar string. Depending on how the string is plucked, the vibrations can be in a vertical direction, horizontal direction, or at any angle perpendicular to the string. In contrast, in longitudinal waves, such as sound waves in a liquid or gas, the displacement of the particles in the oscillation is always in the direction of propagation, so these waves do not exhibit polarization. Transverse waves that exhibit polarization include electromagnetic waves such as light and radio waves, gravitational waves, and transverse sound waves (shear waves) in solids. An electromagnetic wave such as light consists of a coupled oscillating electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Surveillance Radar
Secondary surveillance radar (SSR)''Secondary Surveillance Radar'', Stevens M.C. Artech House, is a radar system used in air traffic control (ATC), that unlike primary radar systems that measure the bearing and distance of targets using the detected reflections of radio signals, relies on targets equipped with a radar Transponder (aviation), transponder, that reply to each interrogation signal by transmitting encoded data such as an identity code, the aircraft's altitude and further information depending on its chosen mode. SSR is based on the military identification friend or foe (IFF) technology originally developed during World War II; therefore, the two systems are still compatible. Monopulse secondary surveillance radar (MSSR), Secondary surveillance radar#Mode S, Mode S, TCAS and ADS-B are similar modern methods of secondary surveillance. Overview Primary radar The rapid World War II, wartime development of radar had obvious applications for air traffic control (ATC) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IFF Display On A-scope
In logic and related fields such as mathematics and philosophy, "if and only if" (often shortened as "iff") is paraphrased by the biconditional, a logical connective between statements. The biconditional is true in two cases, where either both statements are true or both are false. The connective is biconditional (a statement of material equivalence), and can be likened to the standard material conditional ("only if", equal to "if ... then") combined with its reverse ("if"); hence the name. The result is that the truth of either one of the connected statements requires the truth of the other (i.e. either both statements are true, or both are false), though it is controversial whether the connective thus defined is properly rendered by the English "if and only if"—with its pre-existing meaning. For example, ''P if and only if Q'' means that ''P'' is true whenever ''Q'' is true, and the only case in which ''P'' is true is if ''Q'' is also true, whereas in the case of ''P if Q'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Hawker Typhoon Mk IB Of No
A, or a, is the first letter and the first vowel letter of the Latin alphabet, used in the modern English alphabet, and others worldwide. Its name in English is '' a'' (pronounced ), plural ''aes''. It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version is often written in one of two forms: the double-storey and single-storey . The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English, '' a'' is the indefinite article, with the alternative form ''an''. Name In English, the name of the letter is the ''long A'' sound, pronounced . Its name in most other languages matches the letter's pronunciation in open syllables. History The earliest known ancestor of A is ''aleph''—the first letter of the Phoenician ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
