Editing Swept wing (section)

===Postwar advancements===
[[File:MilesM52 1.jpg|thumb|Artist's impression of the Miles M.52]]
During 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 Airport|Farnborough]], and the [[National Physical Laboratory (United Kingdom)|National Physical Laboratory]].<ref name = "wood 29">Wood 1975, p. 29.</ref> The M.52 was envisioned to be capable of achieving {{convert|1000|mph}} in level flight, thus enabling the aircraft to potentially be the first to exceed the speed of sound in the world.<ref name = "wood 29"/> In February 1946, the programme was abruptly discontinued for unclear reasons.<ref name = "wood 34 35">Wood 1975, pp. 34–35.</ref> 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.<ref name="Hallion"/>

Another, more successful, programme 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.<ref name = "wood 36">Wood 1975, p. 36.</ref> On 14 October 1947, the Bell X-1 performed the first manned [[supersonic]] flight, piloted by [[Captain (United States O-3)|Captain]] [[Chuck Yeager|Charles "Chuck" Yeager]], having been [[drop launch]]ed from the bomb bay of a [[Boeing B-29 Superfortress]] and attained a record-breaking speed of Mach 1.06 ({{convert|700|mph|km/h kn}}).<ref name="Hallion"/> 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.{{r|ley194811}}

[[File:DH 108 Swallow tg283.jpg|thumb|right|The [[de Havilland DH 108]], a prototype swept-wing aircraft]]
During the final years of the Second World War, aircraft designer Sir [[Geoffrey de Havilland]] commenced development on 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.<ref>Davies and Birtles 1999, p. 10.</ref> 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 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".<ref>Winchester 2005, p. 78.</ref> 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 a world speed record. On 12 April 1948, a D.H.108 did set a world's speed record at 973.65&nbsp;km/h (605&nbsp;mph), it subsequently became the first jet aircraft to exceed the speed of sound.<ref>{{cite web |title=Eric 'Winkle' Brown obituary |url=https://www.theguardian.com/uk-news/2016/feb/22/eric-winkle-brown-obituary |work=[[The Guardian]] |date=22 February 2016 |access-date=13 August 2016}}</ref>

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.<ref>Buttler 2007, p. 52.</ref> Furthermore, the [[Royal Air Force]] (RAF) identified 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.<ref name = "wood 43 46">Wood 1975, pp. 43–46.</ref> 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 a speed of 727.63&nbsp;mph (1,171.01&nbsp;km/h) over [[Littlehampton]], [[West Sussex]].<ref>[http://www.flightglobal.com/pdfarchive/view/1954/1954%20-%200309.html "R.Ae.C. Award Winners."] ''Flight International'', 5 February 1954. Retrieved: 3 November 2009.</ref> This world record stood for less than three weeks before being broken on 25 September 1953 by the Hunter's early rival, the Supermarine Swift, being flown by Michael Lithgow.<ref>[https://news.google.com/newspapers?id=cilgAAAAIBAJ&sjid=Vm8NAAAAIBAJ&pg=3245,3493974&dq=air+speed+record&hl=en "Speed Record Again Broken?"] ''Saskatoon Star-Phoenix,'' 25 September 1953.</ref>

In February 1945, [[NACA]] engineer [[Robert Thomas Jones (engineer)|Robert T. Jones]] started looking at highly swept [[delta wing]]s and V shapes, and discovered the same effects as Busemann. He finished a detailed report on the concept in April, but found his work was heavily criticised by other members of [[Langley Research Center|NACA Langley]], notably Theodore Theodorsen, who referred to it as "hocus-pocus" and demanded some "real mathematics".<ref name="history" /> However, Jones had already secured some time for [[Free flight (model aircraft)|free-flight models]] under the direction of [[Robert Gilruth]], whose reports were presented at the end of May and showed a fourfold decrease in drag at high speeds. All of this was compiled into a report published on June 21, 1945, which was sent out to the industry three weeks later.<ref>[https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930081951_1993081951.pdf "Wing Planforms for High-Speed Flight."] ''NACA TN-1033.'' Retrieved:  July 24, 2011.</ref> Ironically, by this point Busemann's work had already been passed around.

[[File:Boeing B-47E-65-BW.jpg|thumb|right|The first American swept-wing aircraft, the [[Boeing B-47 Stratojet]]]]
In May 1945, the American [[Operation Paperclip]] reached [[Braunschweig University of Technology|Braunschweig]], where US personnel discovered a number of swept wing models and a mass of technical data from the wind tunnels. One member of the US team was [[George S. Schairer]], who was at that time working at the Boeing company. He immediately forwarded a letter to Ben Cohn at Boeing, communicating the value of the swept wing concept.<ref>Von Karman,'' Aerodynamics: Selected Topics in the Light of their Historical Developments'', 1954.</ref><ref name = "gungil 3940">Gunston and Gilchrist 1993, pp. 39–40.</ref> He also told Cohn to distribute the letter to other companies as well, although only Boeing and North American made immediate use of it.{{Citation needed|date=November 2020}}

Boeing was in the midst of designing the [[Boeing B-47 Stratojet|B-47 Stratojet]], and the initial Model 424 was a straight-wing design similar to the [[B-45 Tornado|B-45]], [[Convair XB-46|B-46]] and [[Martin XB-48|B-48]] it competed with. Analysis by Boeing engineer Vic Ganzer suggested an optimum sweepback angle of about 35 degrees.<ref>Cook 1991, p. 152.</ref> By September 1945, the Braunschweig data had been worked into the design, which re-emerged as the Model 448, a larger six-engine design with more robust wings swept at 35 degrees.<ref name="history" /> Another re-work moved the engines into strut-mounted pods under the wings due to concerns of the uncontained failure of an internal engine could potentially destroy the aircraft via either fire or vibration.<ref name = "gungil 40">Gunston and Gilchrist 1993, p. 40.</ref> The resulting B-47 was hailed as the fastest of its class in the world during the late 1940s,<ref name = "popular 139">Fraser November 1949, p. 139.</ref> and trounced the straight-winged competition. Boeing's jet-transport formula of swept wings and pylon-mounted engines has since been universally adopted.{{Citation needed|date=November 2020}}

In fighters, [[North American Aviation]] was in the midst of working on a straight-wing jet-powered naval fighter, then known as the [[North American FJ-1 Fury|FJ-1]]; it was later submitted to the United States Air Force as the [[North American F-86 Sabre|XP-86]].<ref name="Werrell p.5">{{harvnb|Werrell|2005|p=5.}}</ref> Larry Green, who could read German, studied the Busemann reports and convinced management to allow a redesign starting in August 1945.<ref name="history" /><ref name="Lednicer">Lednicer, David. [http://www.ae.illinois.edu/m-selig/ads/aircraft.html "The Incomplete Guide to Airfoil Usage."] {{Webarchive|url=https://web.archive.org/web/20100420012244/http://www.ae.illinois.edu/m-selig/ads/aircraft.html |date=20 April 2010 }} ''ae.illinois.edu,'' 15 October 2010. Retrieved: 19 July 2011.</ref><ref>Radinger and Schick 1996, p. 32.</ref> The performance of the F-86A allowed it to set the first of several official [[Flight airspeed record|world speed record]]s, attaining {{Convert|671|mph|km/h}} on 15 September 1948, flown by Major [[Dick Johnson (test pilot)|Richard L. Johnson]].<ref>Wagner 1963, {{page needed|date=November 2020}}.</ref> With the appearance of the MiG-15, the F-86 was rushed into combat, while straight-wing jets like the [[Lockheed P-80 Shooting Star]] and [[Republic F-84 Thunderjet]] were quickly relegated to ground attack missions. Some, such as the F-84 and [[Grumman F-9 Cougar]], were later redesigned with swept wings from straight-winged aircraft.<ref name="knaack 42">Knaack 1978, p. 42.</ref><ref name="Kinzey 4">Kinzey 1983, p. 4.</ref> Later planes, such as the [[North American F-100 Super Sabre]], would be designed with swept wings from the start, though additional innovations such as the afterburner, area-rule and new control surfaces would be necessary to master supersonic flight.<ref>{{Cite web |url=http://ftp.rta.nato.int/public//PubFulltext/RTO/TR/RTO-TR-029///TR-029-$$ALL.pdf |title=Archived copy |access-date=4 November 2017 |archive-url=https://web.archive.org/web/20130717062826/http://ftp.rta.nato.int/public/PubFulltext/RTO/TR/RTO-TR-029/TR-029-$$ALL.pdf |archive-date=17 July 2013 |url-status=dead }}</ref><ref name="historynet.com"/>

[[File:MIG-15 Sabre Side-by-Side lower resolution.png|thumb|[[MiG-15]] and [[F-86 Sabre]] Side-by-Side comparison ]]
The [[Soviet Union]] was also quick to investigate the advantages of swept wings on high speed aircraft, when their "captured aviation technology" counterparts to the western Allies spread out across the defeated Third Reich. [[Artem Mikoyan]] was asked by the Soviet government's [[TsAGI]] aviation research department to develop a test-bed aircraft to research the swept wing idea — the result was the late 1945-flown, unusual [[Mikoyan-Gurevich MiG-8|MiG-8]] ''Utka'' [[pusher configuration|pusher]] [[canard (aeronautics)|canard]] layout aircraft, with its rearwards-located wings being swept back for this type of research.<ref>Gunston 1995, p. 184.</ref> The swept wing was applied to the [[MiG-15]], an early jet-powered fighter, its maximum speed of {{convert|1075|km/h|0|abbr=on}} outclassed the straight-winged American jets and piston-engined fighters initially deployed during the [[Korean War]].<ref>Seidov and Britton 2014, p. 554.</ref> The MiG-15 is believed to have been one of [[List of most-produced aircraft|the most produced jet aircraft]]; in excess of 13,000 would ultimately be manufactured.<ref>{{citation |url=http://www.nasm.si.edu/collections/artifact.cfm?id=A19860066000 |title=Mikoyan-Gurevich MiG-15 (Ji-2) Fagot B. |work=Smithsonian National Air and Space Museum |archive-url=https://web.archive.org/web/20151220195312/http://airandspace.si.edu/collections/artifact.cfm?id=A19860066000 |archive-date=20 December 2015 |url-status=dead  }}</ref>
[[File:MiG-17F Top View.JPG|thumb|Soviet MiG-17]]
The MiG-15, which could not safely exceed Mach 0.92, served as the basis for the [[MiG-17]], which was designed to be controllable at higher Mach numbers.<ref>Sweetman 1984, p. 11.</ref> Its wing sweep, 45° near the fuselage ( the same as the [[F-100 Super Sabre]]), changed to 42° for the outboard part of the wing.<ref name="Crosby p. 212.">Crosby 2002, p. 212.</ref> A further derivative of the design, designated [[MiG-19]], featured a relatively thin wing suited to supersonic flight that was designed at TsAGI, the Soviet [[Central Aerohydrodynamic Institute]]; swept back at an angle of 55 degrees, this wing featured a single [[wing fence]] on each side.<ref name="WoF9p124">Gordon 1997, p. 124.</ref> A specialist high-altitude variant, the Mig-19SV, featured, amongst other changes, an adjustable flap to generate greater lift at higher altitudes, helping to increase the aircraft's ceiling from {{convert|17500|m|ft|abbr=on}} to {{convert|18500|m|ft|abbr=on}}.<ref name="melp225-7">Belyakov and Marmain 1994, pp. 225–227.</ref><ref name="gunp197-8">Gunston 1995, pp. 197–198.</ref>

Germany's swept wing research was also obtained by the Swedish aircraft manufacturer [[Saab AB|SAAB]], with the help of ex-Messerschmitt engineers that had fled to [[Switzerland]] during late 1945.<ref name = "erichs 37">Erichs et al. 1988, p. 37.</ref><ref name = "dorr 237">Dorr 2013, p. 237.</ref> At the time, SAAB saw the need to make aeronautical advances, particularly in the new field of jet propulsion.<ref name = "widf 3">Widfeldt 1966, p. 3.</ref> The company incorporated both the jet engine and the swept wing to produce the [[Saab 29 Tunnan]] fighter; on 1 September 1948, the first prototype conducted its maiden flight, flown by the English test pilot [[Squadron leader|S/L]] Robert A. 'Bob' Moore, [[Distinguished Flying Cross (United Kingdom)|DFC]] and bar,<ref name = "flight 558">''Flight'' 1950, p. 558.</ref> Although not well known outside Sweden, the Tunnan was the first Western European fighter to be introduced with such a wing configuration.<ref name = "boyne 547">Boyne 2002, p. 547.</ref><ref name = "saab 1940">[http://saabgroup.com/about-company/history/1940s/ "1940s."] ''Saab'', Retrieved: 27 March 2016.</ref> In parallel, SAAB also developed another swept wing aircraft, the [[Saab 32 Lansen]], primarily to serve as Sweden's standard attack aircraft.<ref name = "saab 1017">''Saab'' 30 December 1960, p. 1017.</ref> Its wing, which had a 10 per cent laminar profile and a 35° sweep, featured triangular fences near the [[wing root]]s in order to improve airflow when the aircraft was being flown at a high [[angle of attack]].<ref name = "saab 1017"/><ref name = "GG 135"/> On 25 October 1953, a SAAB 32 Lansen attained a [[Mach number|Mach]] number of at least 1.12 while in a shallow dive, exceeding the [[supersonic|sound barrier]].<ref name = "GG 135">Gunston and Gilchrist 1993, p. 135.</ref>

The successes of aircraft such as the Hawker Hunter, the B-47, and F-86 showed the value of the swept wing research acquired from Germany. Eventually, almost all advanced design efforts for high speed aircraft would incorporate a wing with a swept leading edge, with either a swept wing or [[delta wing]] [[wing planform|planform]]. The Boeing B-52, designed in the 1950s, continues in service as a subsonic long-range heavy bomber.<ref>{{cite web |url=https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104465/b-52h-stratofortress/ |title=B-52 Stratofortress – U.S. Air Force – Fact Sheet Display |website= af.mil}}</ref><ref>{{cite web |url=https://medium.com/war-is-boring/i-ll-be-damned-these-boneyard-b-52s-can-still-fly-4eec4c8bf5cf |title=I'll Be Damned, These Boneyard B-52s Can Still Fly |first=Joseph |last=Trevithick |date=19 February 2015 |website=Medium}}</ref> While the Soviets never matched the performance of the [[Boeing B-52 Stratofortress]] with a jet aircraft, the intercontinental range [[Tupolev Tu-95]] [[turboprop]] bomber with its near-jet class top speed of 920&nbsp;km/h, combining swept wings with propeller propulsion, also remains in service today, being the fastest propeller-powered production aircraft.<ref>{{cite news |url=http://www.flightglobal.com/news/articles/russian-air-force-takes-first-modernised-tupolev-bombers-407325/ |title=Russian air force takes first modernised Tupolev bombers |work=Flightglobal |first=Dominic |last=Perry |location=London |date=19 December 2014 |access-date=20 November 2015 |archive-url=https://web.archive.org/web/20150927193745/https://www.flightglobal.com/news/articles/russian-air-force-takes-first-modernised-tupolev-bombers-407325/ |archive-date=27 September 2015 |url-status=live |df=dmy-all}}</ref> In Britain, two swept-wing bombers entered service, the [[Vickers Valiant]] (1955)<ref name="Andrews Vickers p439">Andrews and Morgan 1988, p. 439.</ref> and the [[Handley Page Victor]] (1958).<ref name="Barnes p503">Barnes 1976, p. 503.</ref>

By the early 1950s, nearly every new fighter had a swept wing. By the 1960s, most civilian jets also adopted swept wings. Most early transonic and supersonic designs such as the MiG-19 and F-100 used long, highly swept wings. Swept wings would reach Mach 2 on the BAC Lightning, and [[Republic F-105 Thunderchief]], built to operate at low level and very high speed primarily for nuclear strike, but with a secondary air-to-air capability.<ref>The World's Fighting Planes, William Green 1964, Fourth Edition, Macdonald & Co. (Publishers) Ltd., Gulf House, 2 Portman Street, London, W.1,  p. 214</ref> By the late 1960s, the [[McDonnell F-4 Phantom II]], was used in large numbers by air forces influenced by the United States. Variable geometry wings were employed on the American [[General Dynamics F-111 Aardvark|F-111]], [[Grumman F-14 Tomcat]] and Soviet [[Mikoyan MiG-27]], although the idea would be abandoned for the American SST design. After the 1970s, most newer generation fighters optimized for maneuvering air combat since the USAF F-15 and Soviet [[Mikoyan MiG-29]] have employed relatively short-span fixed wings with relatively large wing area.{{Citation needed|date=November 2020}}