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57-514: BAC/Dassault AFVG (standing for Anglo-French Variable Geometry ) was a 1960s project for supersonic multi-role combat aircraft with a variable-sweep wing , jointly developed by British Aircraft Corporation in the United Kingdom and Dassault Aviation of France. The project was borne out of ambitions to produce a viable combat aircraft that made use of the variable-sweep wing, as well as to promote wider cooperative efforts between France and

114-474: A vertical stabiliser and rudder , instead using variable geometry wings to provide primary controllability in their place. In 1946, Wallis published a paper upon this research, which was quickly hailed as being a major scientific breakthrough in the aviation industry. Wallis proceeded to advocate for the production of an aircraft, military or civil, that would take advantage of a variable geometry wing. The Ministry of Supply and Ministry of Defence arranged for

171-540: A demonstrator aircraft, powered by a pair of Rolls-Royce/MAN Turbo RB153 turbofan engines, was also mooted. While funding for the UKVG in the United Kingdom was seriously restricted, the British government sought to find partners in the form of NATO members, promoting the concept of creating and procuring a common NATO strike aircraft. In July 1968, a memorandum of understanding was signed between Britain, West Germany , Italy ,

228-530: A government order for the type to equip the Royal Air Force (RAF), being one of a number of proposed designs that were produced by several rival manufacturers to meet Specification AST.362 . According to aviation author Derek Wood, in spite the P.45 design being "the obvious choice", the Secretary of State for Defence Denis Healey dismissed it in favour of a prospective cooperative arrangement with France for

285-484: A joint-project based on the Br.121 ECAT ("Tactical Combat Support Trainer") proposal from Breguet Aviation instead. Starting in 1964, a series of in-depth discussions took place between the governments of France and UK on prospective collaborative military aviation programs; these involved talks between Handel Davies, the co-chairman of an Anglo-French committee, and his French counterpart, Ingénieur-General Lecamus, negotiating

342-459: A large variable geometry strike aircraft in response to Specification GOR.339 for a nuclear-armed supersonic bomber. In 1964, the newly formed British Aircraft Corporation (BAC) decided to harness Vicker's earlier variable geometry work on a new design study, designated as the BAC P.45. The conceptual BAC P.45 was designed as a 'light strike' and two-seat trainer aircraft. BAC had strongly advocated for

399-505: A larger, variable geometry carrier -capable fighter aircraft for the French Navy ( Aéronavale ) as well as fulfilling interceptor, tactical strike and reconnaissance roles for the RAF. The AFVG was to be jointly developed by BAC and Dassault Aviation , the proposed M45G turbofan engine to power the aircraft was to also be jointly developed by SNECMA and Bristol Siddeley . On 13 July 1965,

456-654: A series of tests to demonstrate the application of the technology to projectiles , both for research purposes and a potential form of anti-aircraft defence ; while Wallis worked upon this research programme, he continued to promote the concept of a manned variable geometry aircraft. In 1951, the Ministry of Supply issued Specification ER.110T , which sought a piloted variable geometry aircraft that would be suitable for research flights; however, ER.110T would be cancelled without an order due to urgent demands for more conventional transonic combat aircraft. At one point, Wallis examined

513-568: A subordinate position to BAC on the AFVG threatened his company's long-term objective of becoming a premier prime contractor for combat aircraft. After less than a year, Dassault began to actively undermine the AFVG project, working on two competing "in-house" projects: the variable geometry Mirage G and the Mirage F1 . According to Wood, both Dassault and the French Air Force had been unenthusiastic for

570-448: A two-engined fighter with four machine guns. So for example, OR.40 for a heavy bomber led to Specification B.12/36. Aircraft manufacturers would be invited to present design proposals to the ministry, following which prototypes of one or more of the proposals might be ordered for evaluation. On very rare occasions, a manufacturer would design and build an aircraft using their own money as a "private venture" (PV). This would then be offered to

627-497: A variable-geometry wing fighter/strike aircraft. From 1945 onwards, Britain conducted a number of studies into the properties and use of variable geometry wings . The noted British engineer and inventor Sir Barnes Wallis began exploring the concept during the Second World War and became an early pioneer and advocate for the variable geometry wing, conceiving of an aircraft consideration that lacked conventional features such as

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684-515: Is actually just a sonic boom . The first human-made supersonic boom was likely caused by a piece of common cloth, leading to the whip's eventual development. It's the wave motion travelling through the bullwhip that makes it capable of achieving supersonic speeds. Most modern firearm bullets are supersonic, with rifle projectiles often travelling at speeds approaching and in some cases well exceeding Mach 3 . Most spacecraft are supersonic at least during portions of their reentry, though

741-444: Is more complex. The main key to having low supersonic drag is to properly shape the overall aircraft to be long and thin, and close to a "perfect" shape, the von Karman ogive or Sears-Haack body . This has led to almost every supersonic cruising aircraft looking very similar to every other, with a very long and slender fuselage and large delta wings, cf. SR-71 , Concorde , etc. Although not ideal for passenger aircraft, this shaping

798-471: Is quite adaptable for bomber use. List of Air Ministry specifications#Post 1949 specifications. Air Staff Operational Requirements This is a partial list of the British Air Ministry (AM) specifications for aircraft . A specification stemmed from an Operational Requirement , abbreviated "OR", describing what the aircraft would be used for. This in turn led to the specification itself, e.g.

855-544: The Black Rock Desert on 15 October 1997. The Bloodhound LSR project planned an attempt on the record in 2020 at Hakskeenpan in South Africa with a combination jet and hybrid rocket propelled car. The aim was to break the existing record, then make further attempts during which (the members of) the team hoped to reach speeds of up to 1,600 km/h (1,000 mph). The effort was originally run by Richard Noble who

912-478: The Handley Page Hampden and Handley Page Hereford . Typographical designation of mark numbers (Mk.) varied over time and inconsistencies are common, e.g., Mark II , Mk. II , II , etc. Initially Roman numerals were used, changing to Arabic numerals post- World War II , e.g., Supermarine Spitfire Mk I to Supermarine Spitfire Mk 24 . Note 1: where possible mark numbers are given here in this list in

969-499: The Manufacturer X.XX/XX , e.g., the Avro B.35/46 – this is in addition to the manufacturer's own separate internal designation for the aircraft, e.g., Avro 698. With several manufacturers submitting designs to the same specification this could result in a number of different aircraft with the same X.XX/XX designation, e.g., Handley Page B.35/46 , etc. Upon acceptance of the design(s)

1026-630: The Manufacturer Service-name , e.g., the Avro Anson , however upon acceptance of a new variant the previous (initial) version automatically became the 'Mark I', so in the example given, the previous (first) version of the Anson retrospectively became the Avro Anson Mk I upon acceptance of an Avro Anson Mk II . Sometimes planned variants would be later cancelled leading to 'missing' mark numbers, or

1083-578: The Ministry of Supply (MoS) in 1946. The system was applied to commercial aircraft as well, two being the de Havilland Comet and Vickers Viscount . During the period, over 800 specifications were issued. Each specification name usually followed a pattern. A leading letter was usually present to identify the aircraft purpose. The codes used included B for "heavy bomber ", e.g., B.12/36, P for "medium bomber", e.g., P.13/36, F for " fighter ", e., F.10/35, and A for "army co-operation", e., A.39/34. The second part

1140-599: The Mutual Weapons Development Programme of NATO , under which all of Wallis' variable geometry research was shared with the Americans. During the mid 1950s, multiple British aircraft manufacturers had become interested in harnessing variable geometry wings in their proposed designs. Amongst these design studies were a supersonic-capable derivative of the Folland Gnat , and a project by Vickers to design

1197-685: The Netherlands , Belgium , and Canada . This memorandum eventually led to the launch of the multinational Multi-Role Combat Aircraft (MRCA) project, which in turn went on to produce a variable geometry aircraft to perform strike, reconnaissance, and interception missions in the form of the Panavia Tornado. Data from Project Cancelled: The Disaster of Britain's Abandoned Aircraft Projects General characteristics Performance Armament Avionics Ground Mapping Radar + TFR Supersonic Sounds are traveling vibrations in

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1254-629: The Tupolev Tu-144 . Both of these passenger aircraft and some modern fighters are also capable of supercruise , a condition of sustained supersonic flight without the use of an afterburner . Due to its ability to supercruise for several hours and the relatively high frequency of flight over several decades, Concorde spent more time flying supersonically than all other aircraft combined by a considerable margin. Since Concorde's final retirement flight on November 26, 2003, there are no supersonic passenger aircraft left in service. Some large bombers , such as

1311-555: The Tupolev Tu-160 and Rockwell B-1 Lancer are also supersonic-capable. The aerodynamics of supersonic aircraft is simpler than subsonic aerodynamics because the airsheets at different points along the plane often cannot affect each other. Supersonic jets and rocket vehicles require several times greater thrust to push through the extra aerodynamic drag experienced within the transonic region (around Mach 0.85–1.2). At these speeds aerospace engineers can gently guide air around

1368-513: The fuselage of the aircraft without producing new shock waves , but any change in cross area farther down the vehicle leads to shock waves along the body. Designers use the Supersonic area rule and the Whitcomb area rule to minimize sudden changes in size. However, in practical applications, a supersonic aircraft must operate stably in both subsonic and supersonic profiles, hence aerodynamic design

1425-682: The AFVG had originally been intended to serve as a fighter, replacing the English Electric Lightning in the interceptor mission. However, following the decision to procure the American-built McDonnell Douglas F-4 Phantom II instead, the AFVG's expected role was changed in 1966 to supplementing the F-111K strike aircraft in replacing the English Electric Canberra and the V bomber force. The AFVG

1482-562: The AFVG programme, the Air Ministry was faced with a dilemma stemming from the imminent prospect of cancelling the F-111K, a decision that was taken in November 1967, to be formalized on 20 March 1968. Up to this point, Britain had spent £2.5 million on the AFVG for practically no gains. In order to justify the absence of any new strike aircraft following the failure of multiple projects to develop or procure one, Healey decided to entirely dismantle

1539-494: The AFVG were complicated by the effort of trying to fit the requirements of both the RAF and the Royal Navy onto a single airframe. Accordingly, as a measure to achieve reasonable performance, two different versions of the AFVG were called for, one being a multirole fighter equipped with pulse-Doppler radar and air-to-air missiles while the other was to be a strike aircraft with limited capability as an interceptor. In June 1967,

1596-759: The BAC Lightning; the British Aircraft Corporation itself and Hawker Siddeley (HS) then later merged and became British Aerospace , subsequently becoming BAe (now BAE Systems ). Thus the previously mentioned Avro Vulcan was subsequently referred to as the Hawker Siddeley Vulcan; similarly, the Blackburn Buccaneer later became the Hawker Siddeley Buccaneer. Where possible, for clarity the aircraft in this list are listed under

1653-530: The French government announced their withdrawal from the AFVG project ostensibly on the grounds of cost. The collapse of the AFVG programme was considerably troubling to the British position, having chosen to rely on Anglo-French collaboration and American-designed combat aircraft to meet its needs. The unilateral French decision led to a censure debate in the House of Commons. By 1967, when the French decided to withdraw from

1710-506: The ORIGINATING company's name or the name of the manufacturer under which it first entered production. Specifications within the tables are listed in numerical order by year of issue; where a given number appears more than once, with one or more letter prefixes, the entries are presented in alphabetical order. In 1917, the Air Board began to issue specifications for new aircraft on behalf of

1767-458: The United Kingdom. However, neither Dassault nor the French Air Force were particularly keen on the AFVG; the project was further impacted by repeated specification changes and indecision for what roles that the AFVG was to be tasked with on the part of Britain. In mid-1967, British requirements settled upon adopting the AFVG for the Royal Air Force (RAF) for the strike role in the place of

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1824-446: The beginning of the 20th century, the term "supersonic" was used as an adjective to describe sound whose frequency is above the range of normal human hearing. The modern term for this meaning is " ultrasonic ", but the older meaning sometimes still lives on, as in the word superheterodyne The tip of a bullwhip is generally seen as the first object designed to reach the speed of sound. This action results in its telltale "crack", which

1881-567: The cancellation of the BAC TSR-2 supersonic tactical and strike bomber, the British and French governments announced the signing of a pair of agreements to cover the two joint projects; one based on the Breguet Aviation Br.121 ECAT ("Tactical Combat Support Trainer") proposal; this would later evolve, after the cancellation of the AFVG, to become the SEPECAT Jaguar . The other was the AFVG,

1938-634: The cancelled BAC TSR-2 strike bomber. The project was cancelled in June 1967, when the French Government withdrew from participation. BAC modified the specification to solely satisfy RAF needs, reconfiguring the design as the UKVG and sought out new partners to procure the aircraft. This ultimately emerged as the Anglo-German-Italian consortium-funded "Multi Role Combat Aircraft" (MRCA), ( Panavia Tornado ),

1995-509: The carrier capabilities that were no longer necessary, into a larger, more strike-oriented variable geometry aircraft. Holding contracts were issued to BAC to support the project, which had been re-designated as the United Kingdom Variable Geometry (UKVG) aircraft. In November 1967, BAC issued a brochure on the UKVG proposal; various proposals would be issued to cover the use of multiple different engines. The quick production of

2052-414: The effects on the spacecraft are reduced by low air densities. During ascent, launch vehicles generally avoid going supersonic below 30 km (~98,400 feet) to reduce air drag. Note that the speed of sound decreases somewhat with altitude, due to lower temperatures found there (typically up to 25 km). At even higher altitudes the temperature starts increasing, with the corresponding increase in

2109-629: The extent of the changes may have justified given the new variant a completely new name, e.g., the Hawker Typhoon II subsequently becoming the Hawker Tempest , or the Avro Lancaster B.IV & B.V entering service as the Avro Lincoln . In a few cases the same aircraft ordered with differing engines would be allocated separate names for each variant, e.g., Hawker Typhoon and Hawker Tornado , or

2166-456: The final service names would usually be chosen by the Air Ministry when they placed a production order, in the above B.35/46 cases, where two aircraft were accepted to this specification, Vulcan and Victor respectively. Upon entering service, in the absence of any already-planned variants a new type would initially have no mark number after the aircraft name, being simply referred to as

2223-410: The form of pressure waves in an elastic medium. Objects move at supersonic speed when the objects move faster than the speed at which sound propagates through the medium. In gases, sound travels longitudinally at different speeds, mostly depending on the molecular mass and temperature of the gas, and pressure has little effect. Since air temperature and composition varies significantly with altitude,

2280-514: The form that was used at the time of acceptance. Variations may be encountered due to changes in format/typographical convention. Note 2: due to mergers and amalgamations within the UK aircraft industry sometimes the name of the manufacturer changed over time, e.g., English Electric later became part of the British Aircraft Corporation (BAC), so the English Electric Lightning then became

2337-437: The launch of two new military combat aircraft. According to these negotiations, the French would take the lead role in developing a new light ground-attack/trainer, while the British were to assume the leadership of a multirole fighter project. This multirole aircraft was to be equipped with a variable geometry wing and was intended to perform the strike , reconnaissance, and interceptor roles. On 17 May 1965, following on from

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2394-452: The letter E (Experimental), e., E.28/39, with training aircraft signified by the letter T (Training), e., T.23/31, and unpowered aircraft , signified by the letter X, e., X.26/40. The letter G (General) signified a general-purpose aircraft, e.g., G.9/45, with an M (Multi-role) being applied to aircraft intended for more than one specific purpose, e.g., M.15/35. The letter C (Cargo) was applied to military transport aircraft, e.g., C.1/42, with

2451-512: The letter O (Observation) used for a naval reconnaissance aircraft, e.g., O.8/38 – the letter S (Spotter) used for the more specialised role of naval spotting, i.e., observing and reporting back the fall of naval gunfire, e.g., S.38/34 – and R (Reconnaissance) for a reconnaissance type – often a flying boat , e.g., R.3/33. Special purpose aircraft would be signified by a letter Q, this being used to specify aircraft such as target-tugs, radio-controlled target drones , etc., e.g., Q.32/55. Sometimes

2508-423: The ministry for evaluation. The ministry may well release a specification based on the private venture aircraft if the plane aroused interest from the RAF or the ministry due to its performance or some other combination of features. The system of producing aircraft to a specification ran from 1920 to 1949 during which the Air Ministry was replaced by first the Ministry of Aircraft Production (MAP) in 1940 and then

2565-545: The naval Spotting role also being used for other purposes, e.g., S.15/33, resulting in the Blackburn Shark and Fairey Swordfish , the latter aircraft being primarily utilised as a torpedo bomber . Similarly S.24/37, which produced the Fairey Barracuda , again primarily designed for spotting, the dive bomber /torpedo bomber requirements being regarded as secondary when the specification was issued, but for which roles it

2622-455: The project from the start, the latter wanting to pursue its own indigenous aircraft equipped with variable geometry wings, while the former had determined that the AFVG did not confirm with any of its future equipment plans. While Britain was keen to procure a capable strike aircraft, France wanted interceptor aircraft; these design requirements of these different roles were relatively exclusive of one another. Britain's own set of requirements for

2679-472: The prospects of producing a variable geometry submission for Specification OR.330 , which sought a supersonic aerial reconnaissance / strategic bomber aircraft. He conceived of a large aircraft equipped with a moveable delta wing configuration, which he dubbed Swallow ; however, midway through scale model free-flight testing, the funding for Wallis' studies was terminated by the Ministry in June 1957. In 1958, research efforts were revived in cooperation with

2736-505: The purpose for which an aircraft is used in service would change from that for which the specification to which it was designed was issued, and so there are some discrepancies and inconsistencies in designation, the Royal Navy in particular liking to specify multiple roles for its aircraft in an attempt to make the best use of the necessarily limited hangar space onboard its aircraft carriers . In this case this resulted in several types designed to specifications originally intended to signify

2793-581: The requirement for one. Thus, in 1968, Prime Minister Harold Wilson , alongside Healey, announced that British troops would be withdrawn in 1971 from major military bases in South East Asia, the Persian Gulf and the Maldives , collectively known as ' East of Suez '. With the prospect of no operational aircraft being available to fulfill the RAF's strike role, BAC decided to revamp the AFVG design, eliminating

2850-429: The specification for the AFVG feasibility study was issued; according to Wood, the specification greatly resembled that which had been earlier issued for the cancelled TSR-2. The AFVG was to have a maximum speed of 800 knots at sea level and Mach 2.5 at altitude. It was required to possess a minimum combat radius of 500 nautical miles, a ferry range of 3,500 nautical miles, and the nose-mounted aircraft interception radar

2907-549: The speed of sound, and Mach numbers for a steadily moving object may change. In water at room temperature supersonic speed means any speed greater than 1,440 m/s (4,724 ft/s). In solids, sound waves can be polarized longitudinally or transversely and have higher velocities. Supersonic fracture is crack formation faster than the speed of sound in a brittle material. The word supersonic comes from two Latin derived words ; 1) super : above and 2) sonus : sound, which together mean above sound, or faster than sound. At

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2964-485: The speed of sound. When an inflated balloon is burst, the torn pieces of latex contract at supersonic speed, which contributes to the sharp and loud popping noise. To date, only one land vehicle has officially travelled at supersonic speed, the ThrustSSC . The vehicle, driven by Andy Green , holds the world land speed record, having achieved an average speed on its bi-directional run of 1,228 km/h (763 mph) in

3021-420: Was a number identifying it in sequence and then after the slash, the year it was formulated, so in the example given above, B.12/36 signifies a specification for a heavy bomber , the twelfth specification of all types issued in 1936 . Specifications were not always issued in sequence. Admiralty specifications were identified by the letter N (Naval), e., N.21/45, and experimental specifications identified by

3078-505: Was almost exclusively subsequently used, the original spotting requirement having been made obsolete with the introduction of radar . In addition, some (mostly early) specifications appear to have no letter prefix at all, e.g., 1/21, the Vickers Virginia III . The names of the aircraft shown in the table are not necessarily those they carried when provided for evaluation as at this point an aircraft would usually be referred to as

3135-560: Was the leader of the ThrustSSC project, however following funding issues in 2018, the team was bought by Ian Warhurst and renamed Bloodhound LSR. Later the project was indefinitely delayed due to the COVID-19 pandemic and the vehicle was put up for sale. Most modern fighter aircraft are supersonic aircraft. No modern-day passenger aircraft are capable of supersonic speed, but there have been supersonic passenger aircraft , namely Concorde and

3192-474: Was to be powered by a pair of SNECMA/Bristol Siddeley M45G turbofans , which were to be fed by Mirage-style half- shock cone inlets. The engine development programme contract was to be issued by the French government to a SNECMA/Bristol Siddeley joint venture company registered in France. For Marcel Dassault, the founder of the firm that bore his name, relinquishing leadership on a major project, essentially taking

3249-542: Was to have a minimum range of 60 nautical miles. Armament was to include a pair of 30 mm cannons and a 2,500 lb tactical nuclear bomb . However, the specification would be repeatedly re-drafted, the issuing of a definitive specification by Whitehall was delayed until April 1966. Wood observed that the requirements of the specification were of a multi-role nature, akin to the Hawker Siddeley P.1154 and variable geometry General Dynamics F-111K . In RAF service,

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