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101-579: The Avro Canada CF-100 Canuck (affectionately known as the "Clunk") is a Canadian twinjet interceptor / fighter designed and produced by aircraft manufacturer Avro Canada . It has the distinction of being the only Canadian-designed fighter to enter mass production . Work commenced in October 1946 in response to a Royal Canadian Air Force (RCAF) specification calling for a new jet-powered interceptor/fighter aircraft suitable for long-distance patrol missions and all-weather operations. On 19 January 1950,

202-470: A fractal surface, such as rocks or soil, and are used by navigation radars. A radar beam follows a linear path in vacuum but follows a somewhat curved path in atmosphere due to variation in the refractive index of air, which is called the radar horizon . Even when the beam is emitted parallel to the ground, the beam rises above the ground as the curvature of the Earth sinks below the horizon. Furthermore,

303-649: A great circle route. Hence, in case of an engine failure in a twinjet (like Boeing 777 ), the twin-jet could make emergency landings in fields in Canada , Alaska , eastern Russia , Greenland , Iceland , or the British Isles . The Boeing 777 has also been approved by the Federal Aviation Administration for flights between North America and Hawaii , which is the world's longest regular airline route with no diversion airports along

404-518: A podded engine usually mounted beneath, or occasionally above or within, each wing. Most notable examples of such a configuration are the Boeing 737 and Airbus A320 . The second has one engine mounted on each side of the rear fuselage, close to its empennage , used by many business jets , although some airliners like the Fokker 70 , Douglas DC-9 and COMAC ARJ21 utilise such a design as well. In

505-424: A transmitter that emits radio waves known as radar signals in predetermined directions. When these signals contact an object they are usually reflected or scattered in many directions, although some of them will be absorbed and penetrate into the target. Radar signals are reflected especially well by materials of considerable electrical conductivity —such as most metals, seawater , and wet ground. This makes

606-482: A different dielectric constant or diamagnetic constant from the first, the waves will reflect or scatter from the boundary between the materials. This means that a solid object in air or in a vacuum , or a significant change in atomic density between the object and what is surrounding it, will usually scatter radar (radio) waves from its surface. This is particularly true for electrically conductive materials such as metal and carbon fibre, making radar well-suited to

707-540: A full radar system, that he called a telemobiloscope . It operated on a 50 cm wavelength and the pulsed radar signal was created via a spark-gap. His system already used the classic antenna setup of horn antenna with parabolic reflector and was presented to German military officials in practical tests in Cologne and Rotterdam harbour but was rejected. In 1915, Robert Watson-Watt used radio technology to provide advance warning of thunderstorms to airmen and during

808-422: A maximum thrust of 28.9 kN (2,950 kgp / 6,500 lbf) thrust. During July 1950, the second prototype, 18102 , performed its first flight. On 5 April 1951, the second prototype was lost in an accident that killed test pilot Bruce Warren. According to aviation author James Dow, this loss resulted in the programme being placed on indefinite hold and questions raised over Avro Canada's competency. In response to

909-749: A physics instructor at the Imperial Russian Navy school in Kronstadt , developed an apparatus using a coherer tube for detecting distant lightning strikes. The next year, he added a spark-gap transmitter . In 1897, while testing this equipment for communicating between two ships in the Baltic Sea , he took note of an interference beat caused by the passage of a third vessel. In his report, Popov wrote that this phenomenon might be used for detecting objects, but he did nothing more with this observation. The German inventor Christian Hülsmeyer

1010-498: A proposal for further intensive research on radio-echo signals from moving targets to take place at NRL, where Taylor and Young were based at the time. Similarly, in the UK, L. S. Alder took out a secret provisional patent for Naval radar in 1928. W.A.S. Butement and P. E. Pollard developed a breadboard test unit, operating at 50 cm (600 MHz) and using pulsed modulation which gave successful laboratory results. In January 1931,

1111-732: A pulsed system, and the first such elementary apparatus was demonstrated in December 1934 by the American Robert M. Page , working at the Naval Research Laboratory . The following year, the United States Army successfully tested a primitive surface-to-surface radar to aim coastal battery searchlights at night. This design was followed by a pulsed system demonstrated in May 1935 by Rudolf Kühnhold and

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1212-442: A rescue. For similar reasons, objects intended to avoid detection will not have inside corners or surfaces and edges perpendicular to likely detection directions, which leads to "odd" looking stealth aircraft . These precautions do not totally eliminate reflection because of diffraction , especially at longer wavelengths. Half wavelength long wires or strips of conducting material, such as chaff , are very reflective but do not direct

1313-408: A specified distance from an available diversion airport. Overwater flights near diversion airports need not be ETOPS/LROPS-compliant. Since the 1990s, airlines have increasingly turned from four-engine or three-engine airliners to twin-engine airliners to operate transatlantic and transpacific flight routes. On a nonstop flight from America to Asia or Europe, the long-range aircraft usually follows

1414-677: A system might do, Wilkins recalled the earlier report about aircraft causing radio interference. This revelation led to the Daventry Experiment of 26 February 1935, using a powerful BBC shortwave transmitter as the source and their GPO receiver setup in a field while a bomber flew around the site. When the plane was clearly detected, Hugh Dowding , the Air Member for Supply and Research , was very impressed with their system's potential and funds were immediately provided for further operational development. Watson-Watt's team patented

1515-541: A trijet aircraft) and Boeing worked on new widebody twinjet designs that would become the Airbus A330 and Boeing 777 , respectively. The MD-11's long range advantage was brief as it was soon nullified by the Airbus A330-300 and the extended-range Boeing 767-300ER and Boeing 777-200ER. The Airbus A320 twinjet stands out as the most produced jet airliner. The Boeing 777X is the world's largest twinjet, and

1616-410: A two-seat fighter, to be crewed by a pilot and navigator, it would adopt two powerful engines along with a relatively advanced radar set and fire control system housed in its nose that would enable the aircraft to be operated in all-weather or night conditions. These requirements were formalized by a RCAF specification that was issued during 1946. According to RCAF Air Marshal Wilfred Curtis , there

1717-514: A wide region and direct fighter aircraft towards targets. Marine radars are used to measure the bearing and distance of ships to prevent collision with other ships, to navigate, and to fix their position at sea when within range of shore or other fixed references such as islands, buoys, and lightships. In port or in harbour, vessel traffic service radar systems are used to monitor and regulate ship movements in busy waters. Meteorologists use radar to monitor precipitation and wind. It has become

1818-907: A writeup on the apparatus was entered in the Inventions Book maintained by the Royal Engineers. This is the first official record in Great Britain of the technology that was used in coastal defence and was incorporated into Chain Home as Chain Home (low) . Before the Second World War , researchers in the United Kingdom, France , Germany , Italy , Japan , the Netherlands , the Soviet Union , and

1919-452: Is a simplification for transmission in a vacuum without interference. The propagation factor accounts for the effects of multipath and shadowing and depends on the details of the environment. In a real-world situation, pathloss effects are also considered. Frequency shift is caused by motion that changes the number of wavelengths between the reflector and the radar. This can degrade or enhance radar performance depending upon how it affects

2020-436: 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 . A radar system consists of a transmitter producing electromagnetic waves in

2121-451: Is as follows, where F D {\displaystyle F_{D}} is Doppler frequency, F T {\displaystyle F_{T}} is transmit frequency, V R {\displaystyle V_{R}} is radial velocity, and C {\displaystyle C} is the speed of light: Passive radar is applicable to electronic countermeasures and radio astronomy as follows: Only

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2222-456: Is attributable to several major procurement programmes that were conducted. During this period, the RCAF had a strong interest in acquiring its own fleet of jet-powered combat aircraft. Specifically, the service had identified a need for a new jet-powered interceptor /fighter aircraft that would be able to patrol the vast areas of Canada's north and operate in all weather conditions. Envisaged as

2323-567: Is intended. Radar relies on its own transmissions rather than light from the Sun or the Moon, or from electromagnetic waves emitted by the target objects themselves, such as infrared radiation (heat). This process of directing artificial radio waves towards objects is called illumination , although radio waves are invisible to the human eye as well as optical cameras. If electromagnetic waves travelling through one material meet another material, having

2424-474: Is not an issue, as one of the engines is more than powerful enough to keep the aircraft aloft (see below). Mostly, ETOPS certification involves maintenance and design requirements ensuring that a failure of one engine cannot make the other one fail also. The engines and related systems need to be independent and (in essence) independently maintained. ETOPS/LROPS is often incorrectly thought to apply only to long overwater flights, but it applies to any flight more than

2525-417: Is the range. This yields: This shows that the received power declines as the fourth power of the range, which means that the received power from distant targets is relatively very small. Additional filtering and pulse integration modifies the radar equation slightly for pulse-Doppler radar performance , which can be used to increase detection range and reduce transmit power. The equation above with F = 1

2626-518: The 777X in November 2013, while then-CEO Fabrice Brégier preferred to focus on product improvement rather than all-new concepts for 10 years. It would have a 10-abreast economy like the 777; its 565 m (6,081 sq ft) wing, slightly more than the 747-8, would have an 80 m (262 ft) span, as wide as the A380 , for a 892,900 lb (405 t) MTOW compared to 775,000 lb (352 t) for

2727-747: The Belgian Air Component . Introduced during 1952 amid the Cold War , the CF-100 was typically deployed at both NATO bases in Europe and in North America as part of North American Aerospace Defense Command (NORAD). In addition to the type's use by frontline squadrons , it was also supplied to operational training units and frequently used for other secondary duties, including aerial reconnaissance and electronic warfare roles. During

2828-399: The Boeing 777 , Boeing 787 and Airbus A350 have matched or surpassed older quad-jet designs such as the Boeing 747 and Airbus A340 in these aspects, and twinjets have been more successful in terms of sales than quad-jets. In 2012, Airbus studied a 470-seat twinjet competitor for the Boeing 747-8 with lower operating costs expected between 2023 and 2030, revived after Boeing launched

2929-571: The CC-117 Falcon . Amid the final years of the Second World War , officials in Canada had concluded both that the development of a self-sufficient indigenous military aviation industry would be of considerable national value and that the new field of jet propulsion held considerable promise. As early as July 1944, Canada had commenced work on its own turbojet engine programme, producing the experimental Avro Canada Chinook powerplant. During

3030-527: The CF-100 Mark 1 prototype, 18101 , conducted its maiden flight , powered by a pair of Rolls-Royce Avon RA 3 turbojet engines. Both pre-production and production series aircraft were powered by the domestically-developed Avro Orenda engine instead. Flight testing proved the CF-100 to possess a relatively short takeoff run and a high climb rate, making it well suited to its role as an interceptor. On 18 December 1952, Squadron Leader Janusz Żurakowski ,

3131-730: The North Atlantic Treaty Organization (NATO), four CF-100 squadrons were based in Europe with 1 Air Division ; for some time, the CF-100 was the only NATO fighter that was capable of operating in zero visibility and poor weather conditions. Around the start of the Korean War in the early 1950s, the United States Air Force (USAF) found itself in urgent need of a jet-propelled, all-weather, interdiction / surveillance aircraft . This urgency

Avro Canada CF-100 Canuck - Misplaced Pages Continue

3232-628: The Nyquist frequency , since the returned frequency otherwise cannot be distinguished from shifting of a harmonic frequency above or below, thus requiring: Or when substituting with F D {\displaystyle F_{D}} : As an example, a Doppler weather radar with a pulse rate of 2 kHz and transmit frequency of 1 GHz can reliably measure weather speed up to at most 150 m/s (340 mph), thus cannot reliably determine radial velocity of aircraft moving 1,000 m/s (2,200 mph). In all electromagnetic radiation ,

3333-717: The RAF's Pathfinder . The information provided by radar includes the bearing and range (and therefore position) of the object from the radar scanner. It is thus used in many different fields where the need for such positioning is crucial. The first use of radar was for military purposes: to locate air, ground and sea targets. This evolved in the civilian field into applications for aircraft, ships, and automobiles. In aviation , aircraft can be equipped with radar devices that warn of aircraft or other obstacles in or approaching their path, display weather information, and give accurate altitude readings. The first commercial device fitted to aircraft

3434-440: The electromagnetic spectrum . One example is lidar , which uses predominantly infrared light from lasers rather than radio waves. With the emergence of driverless vehicles, radar is expected to assist the automated platform to monitor its environment, thus preventing unwanted incidents. As early as 1886, German physicist Heinrich Hertz showed that radio waves could be reflected from solid objects. In 1895, Alexander Popov ,

3535-460: The radio or microwaves 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 information about the objects' locations and speeds. Radar was developed secretly for military use by several countries in

3636-407: The reflective surfaces . A corner reflector consists of three flat surfaces meeting like the inside corner of a cube. The structure will reflect waves entering its opening directly back to the source. They are commonly used as radar reflectors to make otherwise difficult-to-detect objects easier to detect. Corner reflectors on boats, for example, make them more detectable to avoid collision or during

3737-534: The "new boy" Arnold Frederic Wilkins to conduct an extensive review of available shortwave units. Wilkins would select a General Post Office model after noting its manual's description of a "fading" effect (the common term for interference at the time) when aircraft flew overhead. By placing a transmitter and receiver on opposite sides of the Potomac River in 1922, U.S. Navy researchers A. Hoyt Taylor and Leo C. Young discovered that ships passing through

3838-413: The 1920s went on to lead the U.K. research establishment to make many advances using radio techniques, including the probing of the ionosphere and the detection of lightning at long distances. Through his lightning experiments, Watson-Watt became an expert on the use of radio direction finding before turning his inquiry to shortwave transmission. Requiring a suitable receiver for such studies, he told

3939-607: The 53 aircraft that were delivered to the Belgian Air Force. Although originally designed for only 2,000 flight hours, it was found that the Canuck's airframe could serve for over 20,000 hours before needing to be withdrawn. The Belgian aircraft were either scrapped after storage or written off in crashes. Consequently, though the Canadian CF-100 would be replaced in its front line role by the faster CF-101 Voodoo ,

4040-753: The 777-200LR variant has the world's second longest aircraft range (behind Airbus A350-900 ULR). Other Boeing twinjets include the 767 , 757 (With the latter having stopped production, but still in commercial service) and 787 . Competitor Airbus produces the A320 family , the A330 , and the A350 . Some modern commercial airplanes still use four engines ( quad-jets ) like the Airbus A380 and Boeing 747-8 , which are classified as very large aircraft (over 400 seats in mixed-class configurations). Four engines are still used on

4141-432: The 777X, with a composite structure for an operating empty weight of 467,400 lb (212 t), and a 8,150 nmi (15,090 km) range at Mach 0.85. When flying far from diversionary airports (so called ETOPS/LROPS flights), the aircraft must be able to reach an alternate on the remaining engine within a specified time in case of one engine failure. When aircraft are certified according to ETOPS standards, thrust

Avro Canada CF-100 Canuck - Misplaced Pages Continue

4242-592: The Avro company chief development test pilot, took the CF-100 Mk ;4 prototype up to Mach 1.10 in a dive from 14,000 m (45,000 ft), making the type the first straight-winged jet aircraft to achieve controlled supersonic flight. The CF-100 principally served with the Royal Canadian Air Force and Canadian Armed Forces ; it was also procured in small numbers by Belgium to equip

4343-659: The CF-100 for the Belgian Air Force . Additional efforts were made to sell the Canuck to several other nations, including the United States , but no other export customers for the type would be secured. Dow reasoned that the Canuck's poor overseas sales performance caused officials to have little confidence for exporting other aircraft, including the CF-105 Arrow. During the type's production life, 692 CF-100s of different variants were manufactured, including

4444-420: The CF-100's development. At one stage Frost, along with Avro's Chief Aerodynamacist Jim Chamberlin , extensively reworked the original design of the fuselage. On 17 May 1949, in response to the programme's progress, an additional agreement was reached to produce ten pre-production fighters along with 30 Avro Orendas , an indigenously-developed turbojet engine. The CF-100 Mark 1 prototype, 18101 , emerged from

4545-515: The CF-100. Five pre-production Mk 2 test aircraft (serial numbers 18103 - 18107 ) were produced, all fitted with Orenda 2 engines; one was fitted with dual controls and designated a Mk 2T trainer. According to pilot Jacqueline Cochran , the Orenda engine responded noticeably smoother than any of the British or American-built jet engines that she had previously flown. Initial teething issues with

4646-465: The Canuck continued to serve with 414 Squadron of the Canadian Forces, based at CFB North Bay , Ontario ; during its later years, the type was tasked with aerial reconnaissance , training and electronic warfare missions. It was finally withdrawn from service during 1981. After the CF-100 was retired, a number of aircraft still remain across Canada (and elsewhere) as static displays. During

4747-404: The Canuck was affectionately known as the "Clunk", the name has been attributed to the noise produced by the forward landing gear during retraction into its well after takeoff. Another common, less attractive, nickname was the "Lead Sled", a reference to its heavy controls and general lack of maneuverability, a nickname that was shared with a number of other 1950s aircraft. Others included CF-Zero,

4848-533: The NIMBLE BAT ferry program, replacing multiple NATO RCAF squadrons equipped with Canadair Sabre day fighters to provide all-weather defense against Soviet intruders. While flown in the North American theatre, the CF-100 would typically retain a natural metal finish; however, those flying overseas were given a British-style disruptive camouflage scheme: dark sea gray and green on top, light sea gray on

4949-787: The United States, independently and in great secrecy, developed technologies that led to the modern version of radar. Australia, Canada, New Zealand, and South Africa followed prewar Great Britain's radar development, Hungary and Sweden generated its radar technology during the war. In France in 1934, following systematic studies on the split-anode magnetron , the research branch of the Compagnie générale de la télégraphie sans fil (CSF) headed by Maurice Ponte with Henri Gutton, Sylvain Berline and M. Hugon, began developing an obstacle-locating radio apparatus, aspects of which were installed on

5050-681: The Zilch, and the Beast, all references to an aircraft many pilots considered less glamorous than RCAF day fighters like the Canadair Sabre . Operationally, many CF-100s functioned under the US–Canadian North American Air Defense Command (NORAD), which protected North American airspace from Soviet intruders, particularly the threat posed by nuclear-armed bombers . Additionally, between 1956 and 1962, as part of

5151-537: The arrest of Oshchepkov and his subsequent gulag sentence. In total, only 607 Redut stations were produced during the war. The first Russian airborne radar, Gneiss-2 , entered into service in June 1943 on Pe-2 dive bombers. More than 230 Gneiss-2 stations were produced by the end of 1944. The French and Soviet systems, however, featured continuous-wave operation that did not provide the full performance ultimately synonymous with modern radar systems. Full radar evolved as

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5252-479: The beam path caused the received signal to fade in and out. Taylor submitted a report, suggesting that this phenomenon might be used to detect the presence of ships in low visibility, but the Navy did not immediately continue the work. Eight years later, Lawrence A. Hyland at the Naval Research Laboratory (NRL) observed similar fading effects from passing aircraft; this revelation led to a patent application as well as

5353-591: The bottom. During his Avro Canada years, the Chief Development Pilot, S/L Żurakowski , continued to fly as an aerobatic display pilot, with spectacular results, especially at the 1955 Farnborough Airshow where he displayed the CF-100 in a "falling-leaf." He was acclaimed again as the "Great Żura" by many aviation and industry observers who could not believe a large, all-weather fighter could be put through its paces so spectacularly. His performance has been credited with Belgium 's decision to purchase

5454-466: The climatic hangar. A seven-man RCAF team, headed by Flight Lieutenant B. D. Darling, which had previously conducted tests at Namao Air Base , Alberta , were part of the climatic detachment of Central Experimental and Proving Establishment ; testing commenced during the following month. In March 1956, a batch of four CF-100 Canucks were dispatched to Eglin AFB to conduct comparative armament trials, where

5555-491: The company to commence the associated design work. Out of this effort would emerge the XC-100 , a prototype all-weather fighter, which was developed to meet the outstanding specification. Work was initially overseen by Edgar Atkin, Avro Canada's Chief Engineer; a key contributor to the programme was ex- de Havilland aircraft designer John Frost , who was appointed chief design engineer for military projects and thus responsible for

5656-408: The detection of aircraft and ships. Radar absorbing material , containing resistive and sometimes magnetic substances, is used on military vehicles to reduce radar reflection . This is the radio equivalent of painting something a dark colour so that it cannot be seen by the eye at night. Radar waves scatter in a variety of ways depending on the size (wavelength) of the radio wave and the shape of

5757-476: The detection process. As an example, moving target indication can interact with Doppler to produce signal cancellation at certain radial velocities, which degrades performance. Sea-based radar systems, semi-active radar homing , active radar homing , weather radar , military aircraft, and radar astronomy rely on the Doppler effect to enhance performance. This produces information about target velocity during

5858-411: The detection process. This also allows small objects to be detected in an environment containing much larger nearby slow moving objects. Doppler shift depends upon whether the radar configuration is active or passive. Active radar transmits a signal that is reflected back to the receiver. Passive radar depends upon the object sending a signal to the receiver. The Doppler frequency shift for active radar

5959-626: The device in patent GB593017. Development of radar greatly expanded on 1 September 1936, when Watson-Watt became superintendent of a new establishment under the British Air Ministry , Bawdsey Research Station located in Bawdsey Manor , near Felixstowe, Suffolk. Work there resulted in the design and installation of aircraft detection and tracking stations called " Chain Home " along the East and South coasts of England in time for

6060-552: The early 1950s, the Avro Canada CF-103 , an advanced derivative of the CF-100 that adopted a swept wing and was capable of transonic speeds, was in development, but was terminated. Further development of these concepts ultimately led to the Avro Canada CF-105 Arrow . During 1981, all of the remaining RCAF CF-100s were withdrawn from service, having been succeeded in the electronic warfare role by

6161-538: The electric field is perpendicular to the direction of propagation, and the electric field direction is the polarization of the wave. For a transmitted radar signal, the polarization can be controlled to yield different effects. Radars use horizontal, vertical, linear, and circular polarization to detect different types of reflections. For example, circular polarization is used to minimize the interference caused by rain. Linear polarization returns usually indicate metal surfaces. Random polarization returns usually indicate

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6262-473: The entire area in front of it, and then used one of Watson-Watt's own radio direction finders to determine the direction of the returned echoes. This fact meant CH transmitters had to be much more powerful and have better antennas than competing systems but allowed its rapid introduction using existing technologies. A key development was the cavity magnetron in the UK, which allowed the creation of relatively small systems with sub-meter resolution. Britain shared

6363-513: The factory, painted gloss black overall with white lightning bolts running down the fuselage and engines. On 19 January 1950, the CF-100 prototype flew its maiden flight with Gloster Aircraft Company Chief Test Pilot Squadron Leader Bill Waterton (on loan from Gloster, then also part of the Hawker Siddeley group) at the controls. The Mark 1 was powered by a pair of Rolls-Royce Avon RA 3 turbojet engines, each capable of generating

6464-466: The firm GEMA  [ de ] in Germany and then another in June 1935 by an Air Ministry team led by Robert Watson-Watt in Great Britain. In 1935, Watson-Watt was asked to judge recent reports of a German radio-based death ray and turned the request over to Wilkins. Wilkins returned a set of calculations demonstrating the system was basically impossible. When Watson-Watt then asked what such

6565-542: The guns. During 1954, the last 54 of an order for the Mk ;3 were swapped for the more advanced Mk 4 , the total orders for the Mk 4 rose to 510. The Mk 4B version was furnished with more powerful Orenda 11s. Five versions, or marks , were produced. The high-altitude Mk 5 was the final variant, production of which commenced during 1955. This model featured a 1.06 m (3 ft 6 in)-longer wingtip and enlarged tailplane, along with removal of

6666-530: The introduction of ETOPS rules that allowed twin-engine jets to fly long-distance routes that were previously off-limits to them, Airbus was able to further develop the A300 as a medium- to long-range airliner to increased sales; Boeing launched its widebody twinjet, the Boeing 767 , in response. In the 1980s the Boeing 727 was discontinued, as its central engine bay would require a prohibitively expensive redesign to accommodate quieter high-bypass turbofans, and it

6767-449: The largest cargo aircraft capable of transporting outsize cargo , including strategic airlifters . Twin-jets tend to be more fuel-efficient than trijet (three engine) and quad-jet (four engine) aircraft. As fuel efficiency in airliners is a high priority, many airlines have been increasingly retiring trijet and quad-jet designs in favor of twinjets in the twenty-first century. The trijet designs were phased out first, in particular due to

6868-519: The late 1940s and early 1950s, events such as the Korean War and Soviet atomic bomb project had contributed to the rising international tensions of what would become known as the Cold War ; the Canadian Government decided to respond by greatly increasing defense expenditure. The Royal Canadian Air Force (RCAF) was a major recipient of the expanded budget, reaching 46.6% of overall defense expenditure during FY 1951–1952, some of which

6969-762: The late 1950s, an advanced supersonic interceptor, CF-105 Arrow along with the sophisticated Orenda Iroquois engine, was under development by Avro Canada as an intended successor to the CF-100. However, during 1959, work on the CF-105 was terminated following a controversial decision by the Canadian government. Data from General characteristics Performance Armament Avionics Related development Aircraft of comparable role, configuration, and era Related lists Twinjet There are three common configurations of twinjet aircraft. The first, common on large aircraft such as airliners, has

7070-400: The locally developed Orenda powerplant instead, the first of which flying during June 1951. As a result of delays encountered in the development of the Orenda, its selection unavoidably impacted the CF-100 programme's timetable as well. Dissatisfied with the pace of development, Cabinet Minister C. D. Howe informed Avro to suspend work on all other projects and focus its efforts on completing

7171-441: The loss and issues encountered, Avro Canada dismissed several members of the design team and established a special working group to rectify a major structural design error identified. To address the latter, a straightforward modification was developed that could be easily retrofitted into the pre-production aircraft. While both prototypes had been powered by Avon engines, the subsequent pre-production and production series aircraft used

7272-507: The machine guns. The proposed Mk 6 was to have mounted Sparrow II missiles and been powered by afterburning Orenda 11IR engines; this was intended to be adopted as an "interim" fighter prior to the introduction of the more advanced Avro Canada CF-105 Arrow , which was then under development. An advanced derivative of the CF-100 was the CF-103 , which was equipped with a swept wing and projected to be capable of transonic speeds; this

7373-410: The more complicated design and maintenance issues of the middle engine mounted on the stabilizer. Early twinjets were not permitted by ETOPS restrictions to fly long-haul trans-oceanic routes, as it was thought that they were unsafe in the event of failure of one engine, so quad-jets were used. Quad-jets also had higher carrying capacity than comparable earlier twinjets. However, later twinjets such as

7474-508: The ocean liner Normandie in 1935. During the same period, Soviet military engineer P.K. Oshchepkov , in collaboration with the Leningrad Electrotechnical Institute , produced an experimental apparatus, RAPID, capable of detecting an aircraft within 3 km of a receiver. The Soviets produced their first mass production radars RUS-1 and RUS-2 Redut in 1939 but further development was slowed following

7575-531: The outbreak of World War II in 1939. This system provided the vital advance information that helped the Royal Air Force win the Battle of Britain ; without it, significant numbers of fighter aircraft, which Great Britain did not have available, would always have needed to be in the air to respond quickly. The radar formed part of the " Dowding system " for collecting reports of enemy aircraft and coordinating

7676-1370: The period before and during World War II . A key development was the cavity magnetron in the United Kingdom , which allowed the creation of relatively small systems with sub-meter resolution. 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 . The modern uses of radar are highly diverse, including air and terrestrial traffic control, radar astronomy , air-defense systems , anti-missile systems , marine radars to locate landmarks and other ships, aircraft anti-collision systems, ocean surveillance systems, outer space surveillance and rendezvous systems, meteorological precipitation monitoring, radar remote sensing , altimetry and flight control systems , guided missile target locating systems, self-driving cars , and ground-penetrating radar for geological observations. Modern high tech radar systems use digital signal processing and machine learning and are capable of extracting useful information from very high noise levels. Other systems which are similar to radar make use of other parts of

7777-494: The pre-production aircraft were soon resolved. The first production version, designated Mk 3 , made its first flight during October 1952. The Mk 3 incorporated the APG-33 radar and was armed with eight .50 caliber Browning M3 machine guns. The Mk 3CT and Mk 3DT were again dual control versions supplied to operational training units. During mid-January 1955, a CF-100 arrived at Eglin AFB , Florida , for cold-weather tests in

7878-706: The primary tool for short-term weather forecasting and watching for severe weather such as thunderstorms , tornadoes , winter storms , precipitation types, etc. Geologists use specialized ground-penetrating radars to map the composition of Earth's crust . Police forces use radar guns to monitor vehicle speeds on the roads. Automotive radars are used for adaptive cruise control and emergency breaking on vehicles by ignoring stationary roadside objects that could cause incorrect brake application and instead measuring moving objects to prevent collision with other vehicles. As part of Intelligent Transport Systems , fixed-position stopped vehicle detection (SVD) radars are mounted on

7979-432: The radial component of the velocity is relevant. When the reflector is moving at right angle to the radar beam, it has no relative velocity. Objects moving parallel to the radar beam produce the maximum Doppler frequency shift. When the transmit frequency ( F T {\displaystyle F_{T}} ) is pulsed, using a pulse repeat frequency of F R {\displaystyle F_{R}} ,

8080-649: The requirement that an aircraft be able to continue a takeoff if an engine fails after the takeoff decision speed is reached. Thus, with all engines operating, trijets must be able to produce at least 150% of the minimum thrust required to climb and quad-jets 133%. Conversely, since a twinjet will lose half of its total thrust if an engine fails, they are required to produce 200% of the minimum thrust required to climb when both engines are operating. Because of this, twinjets typically have higher thrust-to-weight ratios than aircraft with more engines, and are thus able to accelerate and climb faster. Radar Radar

8181-414: The response. Given all required funding and development support, the team produced working radar systems in 1935 and began deployment. By 1936, the first five Chain Home (CH) systems were operational and by 1940 stretched across the entire UK including Northern Ireland. Even by standards of the era, CH was crude; instead of broadcasting and receiving from an aimed antenna, CH broadcast a signal floodlighting

8282-410: The resulting frequency spectrum will contain harmonic frequencies above and below F T {\displaystyle F_{T}} with a distance of F R {\displaystyle F_{R}} . As a result, the Doppler measurement is only non-ambiguous if the Doppler frequency shift is less than half of F R {\displaystyle F_{R}} , called

8383-427: The roadside to detect stranded vehicles, obstructions and debris by inverting the automotive radar approach and ignoring moving objects. Smaller radar systems are used to detect human movement . Examples are breathing pattern detection for sleep monitoring and hand and finger gesture detection for computer interaction. Automatic door opening, light activation and intruder sensing are also common. A radar system has

8484-407: The scattered energy back toward the source. The extent to which an object reflects or scatters radio waves is called its radar cross-section . The power P r returning to the receiving antenna is given by the equation: where In the common case where the transmitter and the receiver are at the same location, R t = R r and the term R t ² R r ² can be replaced by R , where R

8585-491: The target. If the wavelength is much shorter than the target's size, the wave will bounce off in a way similar to the way light is reflected by a mirror . If the wavelength is much longer than the size of the target, the target may not be visible because of poor reflection. Low-frequency radar technology is dependent on resonances for detection, but not identification, of targets. This is described by Rayleigh scattering , an effect that creates Earth's blue sky and red sunsets. When

8686-530: The technology with the U.S. during the 1940 Tizard Mission . In April 1940, Popular Science showed an example of a radar unit using the Watson-Watt patent in an article on air defence. Also, in late 1941 Popular Mechanics had an article in which a U.S. scientist speculated about the British early warning system on the English east coast and came close to what it was and how it worked. Watson-Watt

8787-694: The third configuration both engines are within the fuselage, side-by-side, used by most fighters since the 1960s. Later fighters using this configuration include the Su-27 'Flanker', the F-15 Eagle , and the F-22 Raptor . The first twinjet to fly was the German fighter prototype Heinkel He 280 , flying in April 1941 with a pair of nacelled Heinkel HeS 8 axial-flow turbojets. The twinjet configuration

8888-879: The transmitter. The reflected radar signals captured by the receiving antenna are usually very weak. They can be strengthened by electronic amplifiers . More sophisticated methods of signal processing are also used in order to recover useful radar signals. The weak absorption of radio waves by the medium through which they pass is what enables radar sets to detect objects at relatively long ranges—ranges at which other electromagnetic wavelengths, such as visible light , infrared light , and ultraviolet light , are too strongly attenuated. Weather phenomena, such as fog, clouds, rain, falling snow, and sleet, that block visible light are usually transparent to radio waves. Certain radio frequencies that are absorbed or scattered by water vapour, raindrops, or atmospheric gases (especially oxygen) are avoided when designing radars, except when their detection

8989-487: The two length scales are comparable, there may be resonances . Early radars used very long wavelengths that were larger than the targets and thus received a vague signal, whereas many modern systems use shorter wavelengths (a few centimetres or less) that can image objects as small as a loaf of bread. Short radio waves reflect from curves and corners in a way similar to glint from a rounded piece of glass. The most reflective targets for short wavelengths have 90° angles between

9090-503: The type was flown by several United States Air Force (USAF) crews. The operational suitability tests, dubbed Project Banana Belt , were carried out by the 3241st Test Group (Interceptor) of the APGC's Air Force Operational Test Center , in conjunction with a project team belonging to the RCAF. During September 1950, the RCAF placed an initial production order for 124 Mk 3 aircraft, the first of which entering service in 1953. This model

9191-472: The use of radar altimeters possible in certain cases. The radar signals that are reflected back towards the radar receiver are the desirable ones that make radar detection work. If the object is moving either toward or away from the transmitter, there will be a slight change in the frequency of the radio waves due to the Doppler effect . Radar receivers are usually, but not always, in the same location as

9292-450: The way. On large passenger jets, the cost of the engines makes up a significant proportion of the plane's final cost. Each engine also requires separate service, paperwork, and certificates. Having two larger engines as opposed to three or four smaller engines will typically significantly reduce both the purchase and maintenance costs of a plane. Regulations governing the required thrust levels for transport aircraft are typically based upon

9393-608: Was a 1938 Bell Lab unit on some United Air Lines aircraft. Aircraft can land in fog at airports equipped with radar-assisted ground-controlled approach systems in which the plane's position is observed on precision approach radar screens by operators who thereby give radio landing instructions to the pilot, maintaining the aircraft on a defined approach path to the runway. Military fighter aircraft are usually fitted with air-to-air targeting radars, to detect and target enemy aircraft. In addition, larger specialized military aircraft carry powerful airborne radars to observe air traffic over

9494-404: Was armed with eight .50 caliber machine guns. The definitive rocket-armed Mk 4A was based on the prototype Mk 4 (a modified Mk 3), which first flew on 11 October 1952. The nose housed the much larger APG-40 radar , while the wings were equipped with wingtip pods, each containing up to 29 Mk 4/Mk 40 "Mighty Mouse" folding-fin aerial rocket , to be used in addition to

9595-465: Was built in mock-up form during 1951, but was considered obsolete even before the CF-100's demonstrated ability to exceed the speed of sound in a dive. On 18 December 1952, Squadron Leader Janusz Żurakowski , the Avro company chief development test pilot, took the CF-100 Mk 4 prototype to Mach 1.0 in a dive from 9,100 m (30,000 ft), becoming the first straight-winged jet aircraft to achieve controlled supersonic flight. Amongst RCAF pilots,

9696-421: Was no existing aircraft that could satisfy the specification, nor was there any suitable aircraft already in development elsewhere, thus it was deemed necessary for Canada to develop such a fighter itself. On 3 November 1945, an agreement was struck to develop a prototype jet-powered fighter on behalf of the RCAF; on 13 October 1946, the issuing of government contracts to aircraft manufacturer Avro Canada enabled

9797-748: Was sent to the U.S. in 1941 to advise on air defense after Japan's attack on Pearl Harbor . Alfred Lee Loomis organized the secret MIT Radiation Laboratory at Massachusetts Institute of Technology , Cambridge, Massachusetts which developed microwave radar technology in the years 1941–45. Later, in 1943, Page greatly improved radar with the monopulse technique that was used for many years in most radar applications. The war precipitated research to find better resolution, more portability, and more features for radar, including small, lightweight sets to equip night fighters ( aircraft interception radar ) and maritime patrol aircraft ( air-to-surface-vessel radar ), and complementary navigation systems like Oboe used by

9898-654: Was so great that the USAF was willing to consider two foreign designs: the CF-100 and the English Electric Canberra . Following an evaluation, the CF-100 was rejected due to its insufficient range and payload capabilities; the rival English Electric design was selected and developed into the Martin B-57 Canberra . At its peak, the CF-100 served with nine RCAF squadrons in the mid-1950s. Four of these squadrons were deployed to Europe under

9999-656: Was soon supplanted by twinjets for the narrow-body market; Airbus with the A320 , and Boeing with the 757 and updated "classic" variants of the 737 . During that decade only McDonnell Douglas continued development of the trijet design with an update to the DC-10 , the MD-11 , which initially had a range advantage over its closest medium wide-body competitors which were twinjets, the in-production Boeing 767 and Airbus A300/A310. In contrast to McDonnell Douglas sticking with their existing trijet configuration, Airbus (which never produced

10100-411: Was the first to use radio waves to detect "the presence of distant metallic objects". In 1904, he demonstrated the feasibility of detecting a ship in dense fog, but not its distance from the transmitter. He obtained a patent for his detection device in April 1904 and later a patent for a related amendment for estimating the distance to the ship. He also obtained a British patent on 23 September 1904 for

10201-484: Was used for short-range narrow-bodied aircraft such as the McDonnell Douglas DC-9 and Boeing 737 . The Airbus A300 was initially not successful when first produced as a short-range widebody, as airlines operating the A300 on short-haul routes had to reduce frequencies to try and fill the high-capacity aircraft, and lost passengers to airlines operating more frequent narrow-body flights. However, after

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