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English Electric Canberra

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A medium bomber is a military bomber aircraft designed to operate with medium-sized bombloads over medium range distances; the name serves to distinguish this type from larger heavy bombers and smaller light bombers . Mediums generally carried about two tons of bombs, compared to light bombers that carried one ton, and heavies that carried four or more.

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150-489: The English Electric Canberra is a British first-generation, jet-powered medium bomber . It was developed by English Electric during the mid- to late 1940s in response to a 1944 Air Ministry requirement for a successor to the wartime de Havilland Mosquito fast bomber. Among the performance requirements for the type was an outstanding high-altitude bombing capability and high speed. These were partly accomplished by making use of newly developed jet-propulsion technology. When

300-517: A bomber design; numerous manufacturers refused to take on the design. Petter left Westland to join the English Electric company in December 1944, where he was appointed by Nelson to form a design team and encouraged to develop his design. In 1945, English Electric formalised its own in-house aircraft design team to pursue this design. The Canberra had its formal origins in a 1944 requirement issued by

450-625: A competition against rivals such as the Martin XB-51 , USAF decided to order a total of 403 Canberras. These aircraft were licence-built by Glenn L. Martin Company as the B-57 Canberra. Martin developed several versions of the aircraft themselves. The first examples were identical to the original English Electric aircraft, following which tandem crew seating was introduced, but later B-57 models were considerably modified. Australia had been interested in

600-442: A design study for a twin-engined fighter-bomber, the P.1056, based on two fuselage-mounted Metrovick F.2/4 "Beryl" engines. The aircraft used a relatively conventional aerodynamic design, Petter having determined that the necessary performance could be attained without adopting swept wings or a swept tail. The authorities doubted its suitability for operations from unprepared fields and at low altitude, but could see its potential as

750-554: A drastically improved performance, and proving to be effectively immune from interception during air defence exercises until the arrival of the Hawker Hunter . The Canberra also replaced the RAF's Mosquitos in the reconnaissance role, with the Canberra PR.3 entering service in December 1952. The improved Canberra B.6, with more powerful engines and a greater fuel capacity, started to supplement

900-450: A few years. The hazard posed by an undercarriage collapse during landing led the RAF to institute regular inspections, at first using radiography before moving to more effective and reliable ultrasound technology. The Canberra structure is mainly metal, with only the forward portion of the tail fin made from wood. Thrust was provided by a pair of 6,700 lbf (30 kN) axial-flow Rolls-Royce Avon turbojet engines. They were mounted in

1050-639: A flypast by a Canberra PR.9 on its last ever sortie was conducted. Shortly after the end of the Second World War, the Australian government initiated a wide-scale reorganisation of the armed forces. As part of this process, the Royal Australian Air Force (RAAF) developed Plan D as the basis for its postwar structure; Plan D was built around the concept of a numerically smaller, but more agile air arm that would employ leading-edge technology. During

1200-418: A higher speed the effects of compressibility (abrupt changes in the density of the airflow), e.g. combat aircraft, airliners and business jets. Other reasons include: 1. enabling a wing carry-through box position to achieve a desired cabin size, e.g. HFB 320 Hansa Jet . 2. providing static aeroelastic relief which reduces bending moments under high g-loadings and may allow a lighter wing structure. For

1350-495: A jet-powered replacement for the Mosquito. To meet the requirement, the B.2 design was modified by adding a 14-inch (36 cm) bay forward of the wing behind the cockpit to house seven cameras. It also had an additional fuel tank in the forward part of the bomb bay and only needed a two-man crew. The prototype, designated PR.3, first flew on 19 March 1950, followed by the first of 35 production aircraft on 31 July 1952. In December 1952,

1500-509: A local indentation of the fuselage above and below the wing root. This proved to not be very effective. During the development of the Douglas DC-8 airliner, uncambered airfoils were used in the wing root area to combat the unsweeping. Swept wings on supersonic aircraft usually lie within the cone-shaped shock wave produced at the nose of the aircraft so they will "see" subsonic airflow and work as subsonic wings. The angle needed to lie behind

1650-462: A means of creating positive longitudinal static stability . For a low-speed aircraft, swept wings may be used to resolve problems with the center of gravity , to move the wing spar into a more convenient location, or to improve the sideways view from the pilot's position. By 1905, Dunne had already built a model glider with swept wings followed by the powered Dunne D.5 , and by 1913 he had constructed successful powered variants that were able to cross

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1800-470: A modified leading edge, increased fuel capacity, and room for three starter cartridges , although in practice, all three cartridges would sometimes fire, leading to the triple starter units being loaded singly. In addition, Australian-built Canberras used a higher proportion of Australian- and US-sourced components. In total, 901 Canberras were manufactured by the various UK-based aircraft manufacturers; when combined with overseas licence production operations,

1950-433: A nominal load of 8,000 pounds (3,600 kg) or more, and light bombers carried up to 2,000 lb (907 kg). These distinctions were beginning to disappear by the middle of World War II, when the average fighter aircraft could now carry a 2,000 lb (907 kg) bombload. Advances in powerplants and designs eventually allowed light bombers , tactical bombers , and later jet fighter-bombers to take over

2100-488: A nuclear bomb to be delivered from low level while allowing the bomber to escape the blast of the weapon. RAF Germany's force of four squadrons equipped with the B(I).6 and B(I).8 could carry US-owned Mark 7 nuclear bombs from 1960, which were replaced by B43 nuclear bombs , also US-owned, from 1965. Three squadrons based on Cyprus and one at Singapore were armed with British-owned Red Beard nuclear weapons. Bomber Command retired

2250-479: A pair of T.64 trainers during the 1970s. From the 1960s onwards, increasing numbers of bomber-oriented Canberras were deemed surplus, as newer, faster ground-attack aircraft were introduced; this led to such aircraft being rebuilt to serve in various alternative roles, including unpiloted target aircraft, radar trainers, target tugs, radar calibration aircraft, and electronic countermeasures trainers. In addition, some Canberras that had originally been manufactured for

2400-422: A pair of proposed fighter aircraft equipped with swept wings from Hawker Aircraft and Supermarine , the Hawker Hunter and Supermarine Swift respectively, and successfully pressed for orders to be placed 'off the drawing board' in 1950. On 7 September 1953, the sole Hunter Mk 3 (the modified first prototype, WB 188 ) flown by Neville Duke broke the world air speed record for jet-powered aircraft, attaining

2550-463: A pressurised nose compartment. The whole lower section of the fuselage is taken up by the sizeable bomb bay with a pair of hydraulically driven doors. The Canberra's undercarriage used a simple arrangement, the main landing gear being equipped with a single outboard-mounted wheel and the nose gear being a twin-wheel arrangement. Due to the use of a new alloy, DTD683, the undercarriage suffered from stress corrosion cracking. Cracks would appear within only

2700-520: A record-breaking speed of Mach 1.06 (700 miles per hour (1,100 km/h; 610 kn)). The news of a successful straight-wing supersonic aircraft surprised many aeronautical experts on both sides of the Atlantic, as it was increasingly believed that a swept-wing design not only highly beneficial but also necessary to break the sound barrier. During the final years of the Second World War, aircraft designer Sir Geoffrey de Havilland commenced development on

2850-468: A simple nature, somewhat resembling a scaled-up Gloster Meteor fighter, except for its use of a mid wing . The Canberra principally differed from its preceding piston-powered wartime bombers by its use of twin Rolls-Royce Avon turbojet engines. The fuselage was circular in cross section, tapered at both ends, and cockpit aside, entirely without protrusions; the line of the large, low- aspect-ratio wings

3000-515: A surge of demand for the Canberra and the British government stepping in to establish a far greater level of wartime production. This led to a succession of orders for Canberra B.2s, the initial bomber variant, being placed with Avro , Handley Page , and Short Brothers ; for British needs alone, English Electric produced 196 B.2s, Avro and Handley Page manufactured 75 each, and Short completed 60 aircraft –

3150-420: A swept wing as it travels through the air. The airflow over a swept wing encounters the wing at an angle. That angle can be broken down into two vectors, one perpendicular to the wing, and one parallel to the wing. The flow parallel to the wing has no effect on it, and since the perpendicular vector is shorter (meaning slower) than the actual airflow, it consequently exerts less pressure on the wing. In other words,

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3300-564: A total of 29 years before its retirement in June 1982. The Canberra was the backbone of the Indian Air Force (IAF) for bombing raids and photo reconnaissance for many decades. Negotiations to acquire the Canberra as a replacement for the obsolete Consolidated B-24 Liberator bombers then being used by IAF began in 1954. During the extended negotiations between Britain and India, the Soviet Union

3450-434: A wing is generated by the airflow over it from front to rear. With increasing span-wise flow the boundary layers on the surface of the wing have longer to travel, and so are thicker and more susceptible to transition to turbulence or flow separation, also the effective aspect ratio of the wing is less and so air "leaks" around the wing tips reducing their effectiveness. The spanwise flow on swept wings produces airflow that moves

3600-419: A wing of given span, sweeping it increases the length of the spars running along it from root to tip. This tends to increase weight and reduce stiffness. If the fore-aft chord of the wing also remains the same, the distance between leading and trailing edges reduces, reducing its ability to resist twisting (torsion) forces. A swept wing of given span and chord must therefore be strengthened and will be heavier than

3750-576: A wing: 1. to arrange the center of gravity of the aircraft and the aerodynamic center of the wing to coincide more closely for longitudinal balance, e.g. Messerschmitt Me 163 Komet and Messerschmitt Me 262 . Although not a swept wing the wing panels on the Douglas DC-1 outboard of the nacelles also had slight sweepback for similar reasons. 2. to provide longitudinal stability for tailless aircraft, e.g. Messerschmitt Me 163 Kometuu . 3. most commonly to increase Mach-number capability by delaying to

3900-534: A world speed record. On 12 April 1948, a D.H.108 did set a world's speed record at 973.65 km/h (605 mph), it subsequently became the first jet aircraft to exceed the speed of sound. Around this same timeframe, the Air Ministry introduced a program of experimental aircraft to examine the effects of swept wings, as well as the delta wing configuration. Furthermore, the Royal Air Force (RAF) identified

4050-601: Is a wing angled either backward or occasionally forward from its root rather than perpendicular to the fuselage. Swept wings have been flown since the pioneer days of aviation. Wing sweep at high speeds was first investigated in Germany as early as 1935 by Albert Betz and Adolph Busemann , finding application just before the end of the Second World War . It has the effect of delaying the shock waves and accompanying aerodynamic drag rise caused by fluid compressibility near

4200-520: Is alleged to have offered their own jet bomber, the Ilyushin Il-28 , at a significantly lower price than that asked for the Canberra; by April 1956, however, the Indian government was in favour of the purchase. In January 1957, India placed a large order for the Canberra; in total, 54 B(I).58 bombers, eight PR.57 photo-reconnaissance aircraft, and six T.4 training aircraft were ordered, and deliveries began in

4350-485: Is forced to rapidly slow and return to ambient pressure. At the point where the density drops, the local speed of sound correspondingly drops and a shock wave can form. This is why in conventional wings, shock waves form first after the maximum Thickness/Chord and why all airliners designed for cruising in the transonic range (above M0.8) have supercritical wings that are flatter on top, resulting in minimized angular change of flow to upper surface air. The angular change to

4500-494: Is important because the leading edge has to be behind the mach cone to reduce wave drag. The quarter chord (25%) line is used because subsonic lift due to angle of attack acts there and, up until the introduction of supercritical sections, the crest was usually close to the quarter chord. Typical sweep angles vary from 0 for a straight-wing aircraft, to 45 degrees or more for fighters and other high-speed designs. Shock waves can form on some parts of an aircraft moving at less than

4650-476: Is no longer used, development of aircraft that fulfil a 'medium bomber' mission in all but name continued and these have been employed in various post-World War II conflicts; examples include dedicated tactical bombers such as the Su-24 , Su-34 , F-111 , J-16 and F-15E which have greater payload and range capability than fighter-bombers, but less than heavier strategic bombers. Swept wing A swept wing

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4800-429: Is placed in an airstream at an angle of yaw – i.e., it is swept back. Now, even if the local speed of the air on the upper surface of the wing becomes supersonic, a shock wave cannot form there because it would have to be a sweptback shock – swept at the same angle as the wing – i.e., it would be an oblique shock. Such an oblique shock cannot form until the velocity component normal to it becomes supersonic." To visualize

4950-452: Is the largest continually curved surface, and therefore the largest contributor to this effect. Sweeping the wing has the effect of reducing the curvature of the body as seen from the airflow, by the cosine of the angle of sweep. For instance, a wing with a 45 degree sweep will see a reduction in effective curvature to about 70% of its straight-wing value. This has the effect of increasing the critical Mach by 30%. When applied to large areas of

5100-558: Is the only modern tactical strike and reconnaissance aircraft in service with the RAF and many other Air Forces. More Canberra aircraft are in service with foreign countries than the Viscount, which holds the record for British civil aircraft. This is due to the flexibility of the Canberra in its operational roles and performance ..." Manufacturer's brochure, 1957. The Canberra could deploy many conventional weapons; typical weapons used were 250-pound, 500-pound, and 1000-pound bombs,

5250-483: The Sabre dance in reference to the number of North American F-100 Super Sabres that crashed on landing as a result. Reducing pitch-up to an acceptable level has been done in different ways such as the addition of a fin known as a wing fence on the upper surface of the wing to redirect the flow to a streamwise direction. The MiG-15 was one example of an aircraft fitted with wing fences. Another closely related design

5400-538: The Blue Danube nuclear weapon) over longer ranges than the Canberra. This led to the Bomber Command force of Canberras equipped for high-level conventional bombing to be gradually phased out. This did not mean the end of the Canberra in front-line service, as it proved suitable for the low-level strike and ground-attack role, and versions dedicated to this role were brought into service. The interim B(I).6, converted from

5550-778: The Cold War , in the Suez Crisis , Vietnam War , Falklands War , Indo-Pakistani wars , and numerous African conflicts. In several wars, each of the opposing sides had Canberras in its air force. The Canberra served for more than 50 years with some operators. In June 2006, the RAF retired the last three of its Canberras 57 years after its first flight. Three of the Martin B-57 variant remain in service, performing meteorological and re-entry tracking work for NASA , as well as providing electronic communication ( Battlefield Airborne Communications Node ) testing for deployment to Afghanistan . During

5700-714: The Commonwealth of Nations . The type was also licence-produced in Australia by Government Aircraft Factories (GAF) and in the US by Martin as the B-57 Canberra . The latter produced both the slightly modified B-57A Canberra and the significantly updated B-57B. In addition to being a tactical nuclear strike aircraft, the Canberra proved to be highly adaptable, serving in varied roles such as tactical bombing and photographic and electronic reconnaissance . Canberras served throughout

5850-683: The English Channel . The Dunne D.5 was exceptionally aerodynamically stable for the time, and the D.8 was sold to the Royal Flying Corps ; it was also manufactured under licence by Starling Burgess to the United States Navy amongst other customers. Dunne's work ceased with the onset of war in 1914, but afterwards the idea was taken up by G. T. R. Hill in England who designed a series of gliders and aircraft to Dunne's guidelines, notably

6000-695: The English Electric Canberra (along with its derived U.S. counterpart, the Martin B-57 ) and the Soviet Ilyushin Il-28 "Beagle". Subsequent to World War II, only the U.S. Strategic Air Command ever used the term "medium bomber" in the 1950s to distinguish its Boeing B-47 Stratojets from somewhat larger contemporary Boeing B-52 Stratofortress "heavy bombers" in bombardment wings (older B-29 and B-50 heavy bombers were also redesignated as "medium" during this period). This nomenclature

6150-455: The Junkers Ju 287 or HFB 320 Hansa Jet . However, larger sweep suitable for high-speed aircraft, like fighters, was generally impossible until the introduction of fly by wire systems that could react quickly enough to damp out these instabilities. The Grumman X-29 was an experimental technology demonstration project designed to test the forward swept wing for enhanced maneuverability during

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6300-654: The Kosovo War in 1999. They were also operated from Uganda during the First Congo War , where they were used to search for refugees. Small numbers of specially equipped Canberras were also used for signals intelligence , being operated by 192 Squadron and then 51 Squadron from 1953 to 1976. During the Falklands War, a plan to supply two PR.9s to the Chilean Air Force, and secretly operate them with RAF crews over

6450-743: The MiG-17 . Political pressure for a Canberra replacement rose to a head in 1962. Australia evaluated the BAC TSR-2 , Dassault Mirage IV , McDonnell Douglas F-4 Phantom II , and North American A-5 Vigilante , and initially appeared to favour the TSR-2, but chose to procure the General Dynamics F-111C in October 1963. Due in part to delays in the delivery of the F-111Cs, the Canberra continued to be used by Australia for

6600-504: The Society of British Aerospace Companies designation A.1 ; work commenced on the construction of these prototype aircraft in that same year, which were all built on production jigs. Progress was slow, however, due to several factors, such as the protracted development of the Avon engine that powered the type; in October 1947, in response to Rolls-Royce's difficulties, English Electric elected to have

6750-520: The Westland-Hill Pterodactyl series. However, Dunne's theories met with little acceptance amongst the leading aircraft designers and aviation companies at the time. The idea of using swept wings to reduce high-speed drag was developed in Germany in the 1930s. At a Volta Conference meeting in 1935 in Italy, Adolf Busemann suggested the use of swept wings for supersonic flight. He noted that

6900-418: The de Havilland Comet , which would become the world's first jet airliner. An early design consideration was whether to apply the new swept-wing configuration. Thus, an experimental aircraft to explore the technology, the de Havilland DH 108 , was developed by the firm in 1944, headed by project engineer John Carver Meadows Frost with a team of 8–10 draughtsmen and engineers. The DH 108 primarily consisted of

7050-663: The inner German border , as well as infrared linescan cameras for low-level night reconnaissance. The RAF used Canberras to search for hidden arms dumps using false-colour photography during Operation Motorman in July 1972, when the British Army re-took Irish republican held "no go areas" in Belfast and Derry . Canberras were used for reconnaissance during the Bosnian War during the 1990s, where they were used to locate mass graves and during

7200-444: The speed of sound , improving performance. Swept wings are therefore almost always used on jet aircraft designed to fly at these speeds. The term "swept wing" is normally used to mean "swept back", but variants include forward sweep , variable sweep wings and oblique wings in which one side sweeps forward and the other back. The delta wing is also aerodynamically a form of swept wing. There are three main reasons for sweeping

7350-412: The 1930s and 1940s, but the breakthrough mathematical definition of sweep theory is generally credited to NACA 's Robert T. Jones in 1945. Sweep theory builds on other wing lift theories. Lifting line theory describes lift generated by a straight wing (a wing in which the leading edge is perpendicular to the airflow). Weissinger theory describes the distribution of lift for a swept wing, but does not have

7500-405: The 1980s. The Sukhoi Su-47 Berkut is another notable demonstrator aircraft implementing this technology to achieve high levels of agility. To date, no highly swept-forward design has entered production. The first successful aeroplanes adhered to the basic design of rectangular wings at right angles to the body of the machine. Such a layout is inherently unstable; if the weight distribution of

7650-484: The Air Ministry for a successor to the de Havilland Mosquito . This requirement, the initial revision being E.3/45 , sought a high-altitude, high-speed bomber , which was to be equipped with no defensive armament. According to aviation historians Bill Gunston and Peter Gilchrist, Air Ministry officials are alleged to have had difficulty defining what they sought for the proposed type, which led to several revisions of

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7800-462: The Alpha bomb. A varied range of munitions was employed on Canberra fleets around the world. Antipersonnel flechette bombs were tested successfully from the Canberra by Rhodesia, but not used operationally due to international agreements. In part due to its range limitation of just 2,000 miles (3,200 km), and its inability to carry the early, bulky nuclear bombs, the Canberra was typically employed in

7950-545: The B.2 variant of the Canberra exceeded the numbers built of any other version. Other nations, notably Australia and the United States of America, also ordered large numbers of Canberras. In the United States, the US Air Force had identified the need to replace the obsolete B-26 Invader , and had determined that, at the time, no home-produced aircraft designs could get close to what the Canberra could already offer. Following

8100-576: The B.2s in the UK based squadrons of Bomber Command from June 1954, when they replaced 101 Squadrons B.2s. This freed up older B.2s to allow Canberra squadrons to form overseas, with bomber and reconnaissance Canberra wings forming in RAF Germany and on Cyprus , with squadrons also being deployed to the Far East. The PR.7 variant of the Canberra, fitted with Avon 109 engines, executed a 1953 reconnaissance flight over

8250-597: The B.6 by adding provision for a pack of four Hispano 20 mm cannon in the rear bomb bay and underwing pylons for bombs and rockets, entered service in 1955, with the definitive, new-build B(I).8, which added a new forward fuselage with a fighter-style canopy for the pilot, entering service in January 1956. During the Cold War the Canberra B6 was used by RAF 76 Squadron to sample atomic and thermo-nuclear mushroom clouds during

8400-618: The British Nuclear Tests in Australia and on Christmas Island . The Canberra B6 were fitted with specialised equipment to collect particulate samples from the mushroom clouds at various heights. It was quite risky as the equipment measuring radiation when they were in the cloud was not always accurate. An important role for the new low-level force was tactical nuclear strike, using the Low Altitude Bombing System to allow

8550-520: The Canberra B.2 WH726 . The USAF also used the Canberra for reconnaissance flights. The aircraft were no longer required after June 1956, following the introduction of the US Lockheed U-2 purpose-built reconnaissance aircraft; Project Robin was then terminated. These RAF Canberra overflights were later featured in the 1994 BBC Timewatch episode; "Spies in the Sky", and included interviews with some of

8700-465: The Canberra bomber, Australia’s major air defence In July 1949, as English Electric was in the process of setting up production at Samlesbury Aerodrome , a firm order was placed for 132 Canberras. The order consisted of 90 B.5/47 bomber-type aircraft, 34 PR.31/46 photo-reconnaissance aircraft, and 8 T.2/49 trainer aircraft. On 25 June 1950, what would become known as the Korean War broke out; this led to

8850-467: The Canberra early on, which had led to the aircraft being named after the Australian capital city. Particular interest had at one time been expressed in a potential Rolls-Royce Tay -powered version of the aircraft. The Government Aircraft Factories locally assembled 48 for the Royal Australian Air Force . These aircraft were broadly similar to the British B.2. Changes included the adoption of

9000-486: The Canberra entered RAF squadron service, No. 101 Squadron being the first to receive the type. In a testament to the aircraft's benign handling characteristics, the transition programme for the Canberra consisted of only 20 hours in the Gloster Meteor and three hours in a dual-control Canberra trainer. Matthew Materia of Smiths Industries was pivotal in a secret Australian Government mission to fit an autopilot system to

9150-593: The Canberra was accelerated as a result of the outbreak of the Korean War, orders for the aircraft increased and outpaced production capacity, as the aircraft was designated as a "super priority". A further five squadrons were able to be equipped with the Canberra by the end of 1952; however, production in the 1951–52 period had only been half of the level planned, due to shortages in skilled manpower, material, and suitable machine tools. The Canberra replaced Mosquitos, Lincolns , and Washingtons as front-line bombers, showing

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9300-445: The Canberra was introduced to service with the Royal Air Force (RAF), the type's first operator, in May 1951, it became the service's first jet-powered bomber. In February 1951, a Canberra set another world record when it became the first jet aircraft to make a nonstop transatlantic flight . Throughout most of the 1950s, the Canberra could fly at a higher altitude than any other aircraft in

9450-414: The English Electric A.1 until it was given the name " Canberra " after the capital of Australia in January 1950 by Sir George Nelson, chairman of English Electric, as Australia had become the aircraft's first export customer. The Air Ministry specification B.3/45 had requested the production of four prototypes. On 9 January 1946, English Electric received a contract to produce four prototypes, which received

9600-454: The Mosquito philosophy, the Canberra by design dispensed with defensive armament, which had historically proven unequal to fighter aircraft , and the resulting performance gain permitted the Canberra to avoid air-to-air combat entirely. On 7 January 1946, the Ministry of Supply placed a contract for the development and production of four English Electric A.1 aircraft. It continued to be known as

9750-516: The PR.3 entered RAF service, when No. 540 Squadron RAF began converting from its Mosquito PR.34 force. The Canberra PR.3 was the first aircraft to be designed for the RAF purely to perform photo-reconnaissance missions. The initial Canberra PR.3 model was shortly succeeded by the improved PR.7 variant, which featured greater fuel capacity via wing storage, the more powerful RA.7 model of the Avon engine, and Maxaret antilock braking system . The Canberra PR.9

9900-516: The Second World War, a desperate demand for bomber aircraft led to many aircraft being produced by secondary manufacturers via licensed manufacturing arrangements. The English Electric company thus mass-produced thousands of piston-engined bombers, such as the Handley Page Hampden and Handley Page Halifax , and the firm became a well-established British aircraft manufacturer despite having little internal design experience. Sir George Nelson ,

10050-624: The Soviet MiG-15 pilots who had attempted to intercept them. The Canberra was the victorious aircraft flown in The Last Great Air Race from London to Christchurch in 1953, piloted by Flight Lieutenant Roland (Monty) Burton , which touched down at Christchurch 41 minutes ahead of its closest rival, after 23 hours and 51 minutes in the air; to this day, the record has never been broken. The Vickers Valiant entered service in 1955, capable of carrying much heavier weapon loads (including

10200-559: The Soviet rocket launch and development site at Kapustin Yar , although the UK government has never admitted the existence of such a flight. Warned by either radar or agents inside the British government, the Soviets slightly damaged one aircraft. Further reconnaissance flights are alleged to have taken place along, and over, the borders of the Soviet Union in 1954 under the code name Project Robin , using

10350-687: The actual aircraft speed is, this becomes a problem during slow-flight phases, such as takeoff and landing. There have been various ways of addressing the problem, including the variable-incidence wing design on the Vought F-8 Crusader , and swing wings on aircraft such as the F-14 , F-111 , and the Panavia Tornado . The term "swept wing" is normally used to mean "swept back", but other swept variants include forward sweep , variable sweep wings and oblique wings in which one side sweeps forward and

10500-434: The air does have time to react, and is pushed spanwise by the angled leading edge, towards the wing tip. At the wing root, by the fuselage, this has little noticeable effect, but as one moves towards the wingtip the airflow is pushed spanwise not only by the leading edge, but the spanwise moving air beside it. At the tip the airflow is moving along the wing instead of over it, a problem known as spanwise flow . The lift from

10650-481: The air that is normally part of lift generation is decreased and this lift reduction is compensated for by deeper curved lower surfaces accompanied by a reflex curve at the trailing edge. This results in a much weaker shock wave towards the rear of the upper wing surface and a corresponding increase in critical mach number. Shock waves require energy to form. This energy is taken out of the aircraft, which has to supply extra thrust to make up for this energy loss. Thus

10800-421: The air would be added to the previously perpendicular airflow, resulting in an airflow over the wing at an angle to the leading edge. This angle results in airflow traveling a greater distance from leading edge to trailing edge, and thus the air pressure is distributed over a greater distance (and consequently lessened at any particular point on the surface). This scenario is identical to the airflow experienced by

10950-414: The aircraft changes even slightly, the wing will want to rotate so its front moves up (weight moving rearward) or down (forward) and this rotation will change the development of lift and cause it to move further in that direction. To make an aircraft stable, the normal solution is to place the weight at one end and offset this with an opposite downward force at the other - this leads to the classic layout with

11100-630: The aircraft is claimed to have handled well, with the exception of rudder overbalance. This initial flight was flown with Avon engines, the decision to perform the type's first flight with the Avon-equipped first prototype or the Nene-equipped second prototype, VN828 , was not made until weeks beforehand. On 9 November 1949, the second prototype, VN828, the first to be equipped with the Nene engine, performed its first flight. The third and fourth followed within

11250-454: The aircraft that was to become the Canberra bore many similarities to the eventual design, despite the placement of a single, centrally mounted turbojet engine; Petter had held discussions with Rolls-Royce Ltd on the topic of the development of a scaled-up derivative of the Nene engine. In late 1945, the design was modified further with a pair of engines being adopted, instead, initially to be set in

11400-567: The aircraft's fuselage. The wingspan and total length of the Canberra are almost identical at just under 65 ft (20 m). Outboard of the engine nacelles , the wing has a leading edge sweep of 4° and trailing edge sweep of −14°. All flight controls are manual, using push rods rather than cables, but are otherwise conventional. These actuate the aircraft's flight control surfaces , including shrouded-nosed ailerons , four-section, conventional, split-type flaps , and atypical airbrakes which comprise 40 hydraulically raised fingers located on

11550-469: The aircraft's nose to accommodate a glazed tip for visual bombing by a bomb aimer, which in turn required the cockpit to be restructured to facilitate the ejection system of the additional crewmember. In 1948, the design team relocated to Warton Aerodrome , Lancashire, establishing a flight-test organisation and assembly facilities there. Ultimately, the first of these prototypes, VN799, conducted its maiden flight on 13 May 1949. Piloted by Roland Beamont ,

11700-422: The aircraft, like the wings and empennage , this allows the aircraft to reach speeds closer to Mach 1. One limiting factor in swept wing design is the so-called "middle effect". If a swept wing is continuous - an oblique swept wing - the pressure isobars will be swept at a continuous angle from tip to tip. However, if the left and right halves are swept back equally, as is common practice, the pressure isobars on

11850-418: The airspeed over the wing was dominated by the normal component of the airflow, not the freestream velocity, so by setting the wing at an angle the forward velocity at which the shock waves would form would be higher (the same had been noted by Max Munk in 1924, although not in the context of high-speed flight). Albert Betz immediately suggested the same effect would be equally useful in the transonic. After

12000-413: The angle of attack at the tip, thus reducing the bending moment on the wing, as well as somewhat reducing the chance of tip stall. However, the same effect on forward-swept wings produces a wash-in effect that increases the angle of attack promoting tip stall. Small amounts of sweep do not cause serious problems, and had been used on a variety of aircraft to move the spar into a convenient location, as on

12150-401: The basic concept of simple sweep theory, consider a straight, non-swept wing of infinite length, which meets the airflow at a perpendicular angle. The resulting air pressure distribution is equivalent to the length of the wing's chord (the distance from the leading edge to the trailing edge). If we were to begin to slide the wing sideways ( spanwise ), the sideways motion of the wing relative to

12300-412: The capability to include chordwise pressure distribution. There are other methods that do describe chordwise distributions, but they have other limitations. Jones' sweep theory provides a simple, comprehensive analysis of swept wing performance. An explanation of how the swept wing works was offered by Robert T. Jones : "Assume a wing is a cylinder of uniform airfoil cross-section, chord and thickness and

12450-400: The chairman of English Electric, decided that the company would seek to remain in the business and produce its own designs. In November 1943, the company was invited to participate in discussions over a prospective bomber that would take advantage of the newly developed jet propulsion technology. In 1944, Westland Aircraft 's technical director and chief designer W. E. W. Petter had prepared

12600-511: The cone increases with increasing speed, at Mach 1.3 the angle is about 45 degrees, at Mach 2.0 it is 60 degrees. The angle of the Mach cone formed off the body of the aircraft will be at about sin μ = 1/M (μ is the sweep angle of the Mach cone) When a swept wing travels at high speed, the airflow has little time to react and simply flows over the wing almost straight from front to back. At lower speeds

12750-454: The course of the war. As early as 1954, Australia recognised that the Canberra was becoming outdated, and evaluated aircraft such as the Avro Vulcan and Handley-Page Victor as potential replacements. The Canberra was incapable of providing adequate coverage of Indonesia from Australian bases, and was evaluated as having a "very low" chance of survival if it encountered modern fighters like

12900-412: The effects of compressibility in transonic and supersonic aircraft because of the reduced pressures. This allows the mach number of an aircraft to be higher than that actually experienced by the wing. There is also a negative aspect to sweep theory. The lift produced by a wing is directly related to the speed of the air over the wing. Since the airflow speed experienced by a swept wing is lower than what

13050-460: The engine in front and the control surfaces at the end of a long boom with the wing in the middle. This layout has long been known to be inefficient. The downward force of the control surfaces needs further lift from the wing to offset. The amount of force can be decreased by increasing the length of the boom, but this leads to more skin friction and weight of the boom itself. This problem led to many experiments with different layouts that eliminates

13200-419: The equivalent unswept wing. A swept wing typically angles backward from its root rather than forwards. Because wings are made as light as possible, they tend to flex under load. This aeroelasticity under aerodynamic load causes the tips to bend upwards in normal flight. Backwards sweep causes the tips to reduce their angle of attack as they bend, reducing their lift and limiting the effect. Forward sweep causes

13350-535: The fastest aircraft of the era were only approaching 400 km/h (249 mph).The presentation was largely of academic interest, and soon forgotten. Even notable attendees including Theodore von Kármán and Eastman Jacobs did not recall the presentation 10 years later when it was re-introduced to them. Hubert Ludwieg of the High-Speed Aerodynamics Branch at the AVA Göttingen in 1939 conducted

13500-766: The first aerial victory of the Pakistan Air Force . Medium bomber The term was used prior to and during World War II , based on available parameters of engine and aeronautical technology for bomber aircraft designs at that time. After the war, medium bombers were replaced in world air forces by more advanced and capable aircraft. In the early 1930s many air forces were looking to modernize their existing bomber aircraft fleets, which frequently consisted of older biplanes . The new designs were typically twin-engined monoplanes , often of all-metal construction, and optimized for high enough performance and speed to help evade rapidly evolving fighter aircraft designs of

13650-565: The first wind tunnel tests to investigate Busemann's theory. Two wings, one with no sweep, and one with 45 degrees of sweep were tested at Mach numbers of 0.7 and 0.9 in the 11 x 13 cm wind tunnel. The results of these tests confirmed the drag reduction offered by swept wings at transonic speeds. The results of the tests were communicated to Albert Betz who then passed them on to Willy Messerschmitt in December 1939. The tests were expanded in 1940 to include wings with 15, 30 and -45 degrees of sweep and Mach numbers as high as 1.21. With

13800-425: The following eight weeks. Flight testing of the prototypes proved to be vice-free and required only a few modifications. The changes included the installation of a glazed nose to accommodate a bomb-aimer, due to the advanced H2S Mk9 bombing radar being unavailable for production, the turbojet engines were replaced by more powerful Rolls-Royce Avon R.A.3s, and distinctive teardrop-shaped fuel tanks were fitted under

13950-433: The high-altitude bomber mission were re-equipped for low-altitude, ground-attack missions. The English Electric Canberra is a bomber aircraft powered by two jet engines, and able to fly at high altitudes. An early prototype operated by Rolls-Royce regularly flew to 63,000 ft, where the usable speed range ( coffin corner ) was only 25 knots, during Avon engine test flights. The overall design has been described as being of

14100-715: The immediate post-war era, several nations were conducting research into high speed aircraft. In the United Kingdom, work commenced during 1943 on the Miles M.52 , a high-speed experimental aircraft equipped with a straight wing that was developed in conjunction with Frank Whittle 's Power Jets company, the Royal Aircraft Establishment (RAE) in Farnborough , and the National Physical Laboratory . The M.52

14250-472: The introduction of jets in the later half of the Second World War , the swept wing became increasingly applicable to optimally satisfying aerodynamic needs. The German jet-powered Messerschmitt Me 262 and rocket-powered Messerschmitt Me 163 suffered from compressibility effects that made both aircraft very difficult to control at high speeds. In addition, the speeds put them into the wave drag regime, and anything that could reduce this drag would increase

14400-560: The last Canberra bombers in RAF service. The RAF continued to operate the Canberra after 1972, employing it for reconnaissance (with squadrons equipped with PR.7s and PR.9s being based at RAF Wyton in the UK and RAF Luqa in Malta). The PR.9s were fitted with special long-range optical photography cameras, reportedly based on those used by the Lockheed U-2, to allow high-altitude photography of targets deep inside Eastern Europe while flying along

14550-552: The last of its Canberras on 11 September 1961, but the Germany, Cyprus and Singapore based squadrons continued in the nuclear strike role. The Cyprus-based squadrons and one of the RAF Germany squadrons disbanded in 1969, with the Singapore-based unit followed in 1970. The three remaining RAF Germany units, which by now had replaced the old Mark 7 bombs with newer (but still US-owned) B43 nuclear bombs, remained operational until 1972,

14700-533: The late 1940s, the RAAF decided to acquire the Canberra as a replacement for, or complement to, the Avro Lincoln, though fears were raised that the new design was not especially advanced. While Australia never introduced nuclear weapons into service, the Canberra's ability to carry such a payload was a stated factor in its acquisition; Australia's planned force of 48 Canberras, which held the potential for being nuclear-armed,

14850-461: The left wing in theory will meet the pressure isobars of the right wing on the centerline at a large angle. As the isobars cannot meet in such a fashion, they will tend to curve on each side as they near the centerline, so that the isobars cross the centerline at right angles to the centerline. This causes an "unsweeping" of the isobars in the wing root region. To combat this unsweeping, German aerodynamicist Dietrich Küchemann proposed and had tested

15000-416: The longer jet pipes and greater yaw during engine-out instances. During the early stages of design, the aircraft had grown from being roughly the same size as the Mosquito to being around double its weight. Although jet-powered, the Canberra design philosophy was very much in the Mosquito mould, providing room for a substantial bomb load, fitting two of the most powerful engines available, and wrapping it in

15150-415: The midsection of the wings using tubular trusses and links between the main mounts and the adjacent leading edge of the wing. Each engine drove a 6 kW generator for the aircraft 28 V DC electrical system, a hydraulic pump for the aircraft hydraulics, and a bleed air system for cabin pressurisation . Fuel was carried in two internally supported self-sealing fuel tanks and a lace-supported bag in

15300-426: The most compact and aerodynamic package possible, an example being a leading edge formed of a single sheet of light alloy wrapped around to 40% of chord, sitting on Redux -bonded stiffeners through which the ribs were passed, the panels secured with adjustable eye-bolts, enabling a highly accurate wing profile to be maintained from the leading edge to main spar without any external joints or fastenings. Also in line with

15450-507: The most crucial of the mission systems was the H2S automatic radar bombsight, which was mounted in the nose; delays in the development of the H2S intended for the Canberra led to early aircraft being fitted with a T.2 optical sight for visual bombing. The optical sight was considerably inferior to radar aiming when used from high altitudes. "The value of the Canberra experience cannot be over-estimated. It

15600-420: The need for the downward force. One such wing geometry appeared before World War I , which led to early swept wing designs. In this layout, the wing is swept so that portions lie far in front and in back of the center of gravity (CoG), with the control surfaces behind it. The result is a weight distribution similar to the classic layout, but the offsetting control force is no longer a separate surface but part of

15750-476: The operational conversion unit, all of the B.2-equipped bomber squadrons received at least one T.4 for training purposes. In addition to the RAF, other users adopted the Canberra in the trainer role. The Indian Air Force operated a number of T.4 aircraft for conversion training purposes. The RAAF adopted the Australian-built Canberra T.21 model, which was broadly similar to the T.4. Argentina procured

15900-433: The other back. The delta wing also incorporates the same advantages as part of its layout. Sweeping a wing forward has approximately the same effect as rearward in terms of drag reduction, but has other advantages in terms of low-speed handling where tip stall problems simply go away. In this case the low-speed air flows towards the fuselage, which acts as a very large wing fence. Additionally, wings are generally larger at

16050-469: The overall global production for the Canberras totalled 1,352 aircraft. With a maximum speed of 470 knots (870 km/h; 540 mph), a standard service ceiling of 48,000 ft (14,600 m), and the ability to carry a 3.6-tonne (7,900 lb) payload, the Canberra proved to be an instant success on the domestic and export markets. It was built in 27 versions that equipped a total of 35 RAF squadrons, and

16200-421: The pairing of the front fuselage of the de Havilland Vampire to a swept wing and small vertical tail; it was the first British swept wing jet, unofficially known as the "Swallow". It first flew on 15 May 1946, a mere eight months after the project's go-ahead. Company test pilot and son of the builder, Geoffrey de Havilland Jr ., flew the first of three aircraft and found it extremely fast – fast enough to try for

16350-458: The performance of their aircraft, notably the notoriously short flight times measured in minutes. This resulted in a crash program to introduce new swept wing designs, both for fighters as well as bombers . The Blohm & Voss P 215 was designed to take full advantage of the swept wing's aerodynamic properties; however, an order for three prototypes was received only weeks before the war ended and no examples were ever built. The Focke-Wulf Ta 183

16500-402: The presentation the host of the meeting, Arturo Crocco , jokingly sketched "Busemann's airplane of the future" on the back of a menu while they all dined. Crocco's sketch showed a classic 1950s fighter design, with swept wings and tail surfaces, although he also sketched a swept propeller powering it. At the time, however, there was no way to power an aircraft to these sorts of speeds, and even

16650-422: The problem. In addition to pitch-up there are other complications inherent in a swept-wing configuration. For any given length of wing, the actual span from tip-to-tip is shorter than the same wing that is not swept. There is a strong correlation between low-speed drag and aspect ratio , the span compared to chord, so a swept wing always has more drag at lower speeds. In addition, there is extra torque applied by

16800-419: The prototype, designated T.4, conducted its first flight. It was the same basic design as the B.2 apart from the introduction of side-by-side seating for the pilot and the instructor and the replacement of the glazed nose with a solid nose. The first production T.4 flew on 20 September 1953 and the variant entered service with No. 231 Operational Conversion Unit RAF in early 1954. In addition to those assigned to

16950-405: The requirement. Further specification refinements, including B.3/45 and B.5/47, issued further details such as a three-man crew and other features such as a visual bombing capability. Several British aircraft manufacturers submitted proposals to meet the requirement, including English Electric. The firm was among those companies to be short-listed to proceed with development studies. By June 1945,

17100-426: The role of a tactical bomber as opposed to that of a strategic one. In British service, many of the Canberras that were stationed overseas were not modified to deliver nuclear weapons until as late as 1957. The Canberra B.2 started to enter service with 101 Squadron in January 1951, with 101 Squadron being fully equipped by May, and a further squadron, No. 9 Squadron equipping by the end of the year. The production of

17250-501: The roles performed by mediums. After the war, use of the term generally vanished; some of this was due to mass demobilization of the participant air forces' existing equipment, and the fact that several of the most-produced medium bomber types were now technologically obsolescent. Although a number of later aircraft were designed in this performance and load-carrying range, they were henceforth referred to as tactical bombers or strike aircraft instead. Examples of post-war mediums include

17400-431: The root anyway, which allows them to have better low-speed lift. However, this arrangement also has serious stability problems. The rearmost section of the wing will stall first causing a pitch-up moment pushing the aircraft further into stall similar to a swept back wing design. Thus swept-forward wings are unstable in a fashion similar to the low-speed problems of a conventional swept wing. However unlike swept back wings,

17550-484: The second prototype modified to use the existing Nene engine in place of the Avon. The implementation of postwar military cutbacks also served to slow development. Another external issue that affected development was the failure of the Telecommunications Research Establishment to produce the radar bombing system for the aircraft in a timely fashion. This required a redesign in 1947, changing

17700-426: The shocks are seen as a form of drag . Since the shocks form when the local air velocity reaches supersonic speeds, there is a certain " critical mach " speed where sonic flow first appears on the wing. There is a following point called the drag divergence mach number where the effect of the drag from the shocks becomes noticeable. This is normally when the shocks start generating over the wing, which on most aircraft

17850-403: The speed of sound. Low-pressure regions around an aircraft cause the flow to accelerate, and at transonic speeds this local acceleration can exceed Mach 1. Localized supersonic flow must return to the freestream conditions around the rest of the aircraft, and as the flow enters an adverse pressure gradient in the aft section of the wing, a discontinuity emerges in the form of a shock wave as the air

18000-402: The stagnation point on the leading edge of any individual wing segment further beneath the leading edge, increasing effective angle of attack of wing segments relative to its neighbouring forward segment. The result is that wing segments farther towards the rear operate at increasingly higher angles of attack promoting early stall of those segments. This promotes tip stall on back-swept wings, as

18150-518: The summer of that same year. Twelve more Canberras were ordered in September 1957, and as many as 30 more may have also been purchased by 1962. On 10 April 1959, an Indian Canberra was shot down while performing a Reconnaissance mission over Rawalpindi . The Canberra was shot down by a F-86F Sabre flown by Flight Lieutenant M Younis. The two crew members of the Canberra ejected and were later arrested by Pakistani authorities. This incident also marked

18300-540: The swept wing design used by most modern jet aircraft, as this design performs more effectively at transonic and supersonic speeds. In its advanced form, sweep theory led to the experimental oblique wing concept. Adolf Busemann introduced the concept of the swept wing and presented this in 1935 at the Fifth Volta Conference in Rome. Sweep theory in general was a subject of development and investigation throughout

18450-445: The time the first prototype had flown, the Air Ministry had placed orders for 132 production aircraft in bomber, reconnaissance, and training variants. On 21 April 1950, the first production-standard aircraft, designated as the Canberra B.2, conducted its maiden flight, piloted by Beamont. Proving to be free of problems, this first flight was almost immediately followed by the mainstream manufacturing of production Canberras. In May 1951,

18600-562: The time. Some of these bombers, such as the Heinkel He 111 , Junkers Ju 86 , Savoia-Marchetti SM.79 , Douglas B-18 , and Armstrong Whitworth Whitley were developed from or in conjunction with existing airliners or transport aircraft. The World War II-era medium bomber was generally considered to be any level bomber design that delivered about 4,000 pounds (1,800 kg) of ordnance over ranges of about 1,500 to 2,000 mi (2,400 to 3,200 km). Typical heavy bombers were those with

18750-411: The tips are most rearward, while delaying tip stall for forward-swept wings, where the tips are forward. With both forward and back-swept wings, the rear of the wing will stall first creating a nose-up moment on the aircraft. If not corrected by the pilot the plane will pitch up, leading to more of the wing stalling and more pitch up in a divergent manner. This uncontrollable instability came to be known as

18900-450: The tips on a forward swept design will stall last, maintaining roll control. Forward-swept wings can also experience dangerous flexing effects compared to aft-swept wings that can negate the tip stall advantage if the wing is not sufficiently stiff. In aft-swept designs, when the airplane maneuvers at high load factor the wing loading and geometry twists the wing in such a way as to create washout (tip twists leading edge down). This reduces

19050-467: The tips to increase their angle of attack as they bend. This increases their lift causing further bending and hence yet more lift in a cycle which can cause a runaway structural failure. For this reason forward sweep is rare and the wing must be unusually rigid. There are two sweep angles of importance, one at the leading edge for supersonic aircraft and the other 25% of the way back from the leading edge for subsonic and transonic aircraft. Leading edge sweep

19200-421: The top and bottom surfaces of the wings. Swept wings were considered, but not adopted, since the expected operational speeds did not warrant them and because they could have introduced new aerodynamic problems into what was otherwise anticipated to be a straightforward replacement for RAF Hawker Typhoon and Westland Whirlwind fighter-bombers. The fuselage of the Canberra is of semi-monocoque construction with

19350-514: The total bomb load could weigh up to 10,000 lb (4,500 kg). Two bomb-bays are housed within the fuselage, normally enclosed by conventional clam-shell doors; a rotating door was substituted for these on the Martin-built B-57 Canberras. Additional stores of up to 2,000 pounds (900 kg) could be carried upon underwing pylons. Operators often developed and installed their own munitions, such as Rhodesia's antipersonnel bomblets,

19500-657: The upper fuselage. The manufacturer specified that Coffman engine starters should be used for engine starting. An improvised method using compressed air was discouraged by Rolls-Royce, but some operators used air starting successfully, the benefit being significant cost savings over the use of cartridges. Various avionics were installed on the Canberra, many with their origins during the Second World War. They included Gee-H navigation , Rebecca beacon-interrogation distance-measuring equipment , very high frequency radio, radio compass , radar altimeter , identification friend or foe , and Orange Putter radar warning receiver . Perhaps

19650-500: The war zone, was abandoned for political reasons. The aircraft got as far as Belize before the operation was cancelled. The PR.9 variant remained in service with No. 39 (1 PRU) Squadron until July 2006 for strategic reconnaissance and photographic mapping, seeing service in the 2003 invasion of Iraq , and up to June 2006, in Afghanistan . During a ceremony to mark the standing down of 39 (1 PRU) Squadron at RAF Marham on 28 July 2006,

19800-448: The wing experiences airflow that is slower - and at lower pressures - than the actual speed of the aircraft. One of the factors that must be taken into account when designing a high-speed wing is compressibility , which is the effect that acts upon a wing as it approaches and passes through the speed of sound . The significant negative effects of compressibility made it a prime issue with aeronautical engineers. Sweep theory helps mitigate

19950-447: The wing roots and later to be mounted in a midwing position; this change was made principally due to centre of gravity issues imposed by the position and weight of a heavy bombload and centrally mounted single engine. The new engine position decreased the aircraft's weight by 13% and improved the aircraft's centre of gravity, as well as improved accessibility to the engines and related accessories; its downsides were slight thrust loss from

20100-469: The wing to the fuselage which has to be allowed for when establishing the transfer of wing-box loads to the fuselage. This results from the significant part of the wing lift which lies behind the attachment length where the wing meets the fuselage. Sweep theory is an aeronautical engineering description of the behavior of airflow over a wing when the wing's leading edge encounters the airflow at an oblique angle. The development of sweep theory resulted in

20250-524: The wing, which would have existed anyway. This eliminates the need for separate structure, making the aircraft have less drag and require less total lift for the same level of performance. These layouts inspired several flying wing gliders and some powered aircraft during the interwar years. The first to achieve stability was British designer J. W. Dunne who was obsessed with achieving inherent stability in flight. He successfully employed swept wings in his tailless aircraft (which, crucially, used washout ) as

20400-487: The wingtips. Refinements were also made following early flight testing to the rudder and elevator to reduce instances of buffeting , after which it is claimed that the Canberra handled much like a fighter, proving to be atypically manoeuvrable for a bomber. The project had found considerable support from the government in the late 1940s. In March 1949, in advance of the maiden flight of the first prototype, English Electric received an instruction to proceed for production. By

20550-409: The world, and in 1957, a Canberra established a world altitude record of 70,310 feet (21,430 m). Due to its ability to evade the early jet interceptor aircraft, and its significant performance advancement over contemporary piston -engined bombers, the Canberra became a popular aircraft on the export market, being procured for service in the air forces of many nations both inside and outside of

20700-564: Was another swept wing fighter design, but was also not produced before the war's end. In the post-war era, Kurt Tank developed the Ta 183 into the IAe Pulqui II , but this proved unsuccessful. A prototype test aircraft, the Messerschmitt Me P.1101 , was built to research the tradeoffs of the design and develop general rules about what angle of sweep to use. When it was 80% complete, the P.1101

20850-445: Was broken only by the tubular engine nacelles . The Canberra had a two-man crew in a fighter-style cabin with a large blown canopy, but delays in the development of the intended automatic radar bombsight resulted in the addition of a bomb aimer's position housed within the nose. The pilot and navigator were positioned in a tandem arrangement on Martin-Baker ejection seats. The wing is of single-spar construction that passes through

21000-543: Was captured by US forces and returned to the United States , where two additional copies with US-built engines carried on the research as the Bell X-5 . Germany's wartime experience with the swept wings and its high value for supersonic flight stood in strong contrast to the prevailing views of Allied experts of the era, who commonly espoused their belief in the impossibility of manned vehicles travelling at such speeds. During

21150-517: Was delivered to the RAAF for service trials a few weeks later. In December 1953, the Canberra formally entered Australian service. From July 1950 to July 1960, during the Malayan Emergency , Canberras from Australia, New Zealand, and the UK were deployed into Malaysia to fight against Communist guerrillas . In 1967, the RAAF deployed eight Canberras to the Vietnam War. The unit, No. 2 Squadron ,

21300-460: Was envisioned to be capable of achieving 1,000 miles per hour (1,600 km/h) in level flight, thus enabling the aircraft to potentially be the first to exceed the speed of sound in the world. In February 1946, the programme was abruptly discontinued for unclear reasons. It has since been widely recognised that the cancellation of the M.52 was a major setback in British progress in the field of supersonic design. Another, more successful, programme

21450-424: Was exported to more than 15 countries: Australia, Argentina, Chile , Ecuador , Ethiopia , France, India, New Zealand, Pakistan, Peru , Rhodesia , South Africa, Sweden, Venezuela , and West Germany. During the latter part of the Second World War, strategic reconnaissance missions performed by the RAF had been carried out by the de Havilland Mosquito. In 1946, the Air Ministry issued Specification PR.31/46 seeking

21600-852: Was later commended for its performance by the United States Air Force. The Canberras were typically operated in the low-level bombing role, taking responsibility for South Vietnam's southernmost military regions, regions III and IV, and allowing USAF bombers to deploy their aircraft to the Ho Chi Minh trail . While USAF Canberras were equipped with .50 caliber machine guns or 20 mm cannon for strafing, Australian Canberras were deployed to South Vietnam without guns, hence were deployed strictly for low-level bombing missions. Upon their redeployment from Vietnam in 1971, No. 2 Squadron had flown about 12,000 sorties and dropped 76,389 bombs, and lost two of their aircraft to missiles and ground fire during

21750-512: Was purely semantic and bureaucratic, however as both the B-47 and B-52 strategic bombers were much larger and had far greater performance and load-carrying ability than any of the World War II-era heavy or medium bombers. Similarly, the Royal Air Force referred at times to its V bomber force as medium bombers, but this was in terms of range rather than load-carrying capacity. Although the term

21900-589: Was the US's Bell X-1 , which also was equipped with a straight wing. According to Miles Chief Aerodynamicist Dennis Bancroft, the Bell Aircraft company was given access to the drawings and research on the M.52. On 14 October 1947, the Bell X-1 performed the first manned supersonic flight, piloted by Captain Charles "Chuck" Yeager , having been drop launched from the bomb bay of a Boeing B-29 Superfortress and attained

22050-523: Was the addition of a dogtooth notch to the leading edge, used on the Avro Arrow interceptor. Other designs took a more radical approach, including the Republic XF-91 Thunderceptor 's wing that grew wider towards the tip to provide more lift at the tip. The Handley Page Victor was equipped with a crescent wing , with three values of sweep, about 48 degrees near the wing root where the wing

22200-452: Was the final photo-reconnaissance version; this aircraft was furnished with a new crew compartment, a redesigned inner wing section, and much more powerful RA.24 Avons. In later service, bomber models of the Canberra were often converted with cameras and other equipment suited for reconnaissance purposes. To enable crews to convert to flying the Canberra, a trainer version was developed to meet Air Ministry Specification T.2/49. On 12 June 1951,

22350-471: Was thickest, a 38 degree transition length and 27 degrees for the remainder to the tip. Modern solutions to the problem no longer require "custom" designs such as these. The addition of leading-edge slats and large compound flaps to the wings has largely resolved the issue. On fighter designs, the addition of leading-edge extensions , which are typically included to achieve a high level of maneuverability, also serve to add lift during landing and reduce

22500-500: Was viewed as far more potent and deterring to potential opponents than the RAAF's entire wartime forces of 254 heavy bombers. The Australian government decided that the RAAF's Canberras would be constructed domestically by the Government Aircraft Factories as opposed to being manufactured in the UK. On 29 May 1953, the first Australian-built Canberra performed its first flight at Avalon Airport , Victoria; this aircraft

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