Misplaced Pages

#558441

140-596: Concorde ( / ˈ k ɒ ŋ k ɔːr d / ) is a retired Anglo-French supersonic airliner jointly developed and manufactured by Sud Aviation (later Aérospatiale ) and the British Aircraft Corporation (BAC). Studies started in 1954, and France and the United Kingdom signed a treaty establishing the development project on 29 November 1962, as the programme cost was estimated at £70 million (£1.68 billion in 2023). Construction of

280-411: A droop nose for landing visibility. It is powered by four Rolls-Royce/Snecma Olympus 593 turbojets with variable engine intake ramps , and reheat for take-off and acceleration to supersonic speed. Constructed out of aluminium , it was the first airliner to have analogue fly-by-wire flight controls. The airliner had transatlantic range while supercruising at twice the speed of sound for 75% of

420-409: A British design (as they had on the earlier subsonic Caravelle ). As neither company had experience in the use of heat-resistant metals for airframes, a maximum speed of around Mach 2 was selected so aluminium could be used – above this speed, the friction with the air heats the metal so much that it begins to soften. This lower speed would also speed development and allow their design to fly before

560-509: A European company, and the risk of "giving away" US technological leadership to a European partner. When the STAC plans were presented to the UK cabinet, the economic considerations were considered highly questionable, especially as these were based on development costs, now estimated to be £ 150 million ( US$ 420 million), which were repeatedly overrun in the industry. The Treasury Ministry presented

700-548: A change in the public opinion of SSTs. By 1976 the remaining buyers were from four countries: Britain, France, China, and Iran. Only Air France and British Airways (the successor to BOAC) took up their orders, with the two governments taking a cut of any profits. The US government cut federal funding for the Boeing 2707 , its supersonic transport programme, in 1971; Boeing did not complete its two 2707 prototypes. The US, India, and Malaysia all ruled out Concorde supersonic flights over

840-543: A class, can supply increased fuel efficiency at supersonic speeds, even though their specific fuel consumption is greater at higher speeds. Because their speed over the ground is greater, this decrease in efficiency is less than proportional to speed until well above Mach 2, and the consumption per unit distance is lower. When Concorde was being designed by Aérospatiale – BAC , high bypass jet engines (" turbofan " engines) had not yet been deployed on subsonic aircraft. Had Concorde entered service against earlier designs like

980-474: A clause, originally asked for by the UK government, imposing heavy penalties for cancellation. This treaty was signed on 29 November 1962. Charles de Gaulle vetoed the UK's entry into the European Community in a speech on 25 January 1963. At Charles de Gaulle's January 1963 press conference the aircraft was first called 'Concorde'. The name was suggested by the eighteen-year-old son of F.G. Clark,

1120-629: A committee to study supersonic transport . The group met in February 1954 and delivered their first report in April 1955. Robert T. Jones ' work at NACA had demonstrated that the drag at supersonic speeds was strongly related to the span of the wing. This led to the use of short-span, thin trapezoidal wings such as those seen on the control surfaces of many missiles, or aircraft such as the Lockheed F-104 Starfighter interceptor or

1260-473: A compromise in performance is chosen, often to the detriment of low speed flight. For example, Concorde had very high drag (a lift to drag ratio of about 4) at slow speed, but it travelled at high speed for most of the flight. Designers of Concorde spent 5000 hours optimizing the vehicle shape in wind tunnel tests to maximize the overall performance over the entire flightplan. The Boeing 2707 featured swing wings to give higher efficiency at low speeds, but

1400-400: A consistent theory of flow around an aircraft. This was, however, an approximation, using singularities to represent the vortices that generated lift, and Weber was given the task of improving it. She realised that some of her work overlapped with Küchemann's research on jet engine intakes. They teamed up, with Weber doing the theoretical development and wind tunnel testing, and Küchemann setting

1540-542: A controlled dive during a test flight at Edwards Air Force Base. The crew were William Magruder (pilot), Paul Patten (copilot), Joseph Tomich (flight engineer), and Richard H. Edwards (flight test engineer). This is the first supersonic flight by a civilian airliner. In total, 20 Concordes were built: two prototypes, two development aircraft and 16 production aircraft. Of the sixteen production aircraft, two did not enter commercial service and eight remained in service as of April 2003. All but two of these aircraft are preserved;

SECTION 10

#1732772998559

1680-411: A delta wing running most of the length of the fuselage, this was no longer easy; moving the wing would leave it in front of the nose or behind the tail. Studying the various layouts in terms of CG changes, both during design and changes due to fuel use during flight, the ogee planform immediately came to the fore. To test the new wing, NASA assisted the team by modifying a Douglas F5D Skylancer to mimic

1820-523: A digital processor for intake control. It was the first use of a digital processor with full authority control of an essential system in a passenger aircraft. It was developed by BAC's Electronics and Space Systems division after the analogue AICUs (developed by Ultra Electronics ) fitted to the prototype aircraft were found to lack sufficient accuracy. Ultra Electronics also developed Concorde's thrust-by-wire engine control system. Engine failure causes problems on conventional subsonic aircraft ; not only does

1960-417: A dump door, an auxiliary inlet and a ramp bleed to the exhaust nozzle. As well as supplying air to the engine, the intake also supplied air through the ramp bleed to the propelling nozzle. The nozzle ejector (or aerodynamic) design, with variable exit area and secondary flow from the intake, contributed to good expansion efficiency from take-off to cruise. Concorde's Air Intake Control Units (AICUs) made use of

2100-415: A few decades. These materials, such as carbon fibre and Kevlar are much stronger for their weight (important to deal with stresses) as well as being more rigid. As per-seat weight of the structure is much higher in an SST design, structural improvements would have led to a greater proportional improvement than the same changes in a subsonic aircraft. Higher fuel costs and lower passenger capacities due to

2240-433: A guide and means of comparison, observing that no detectable ozone loss was evident from approximately 213 megatons of explosive energy being released in 1962, so therefore the equivalent amount of NOx from "1047" Concordes flying "10 hours a day", would likewise, not be unprecedented. In 1981 models and observations were still irreconcilable. More recent computer models in 1995 by David W. Fahey, an atmospheric scientist at

2380-442: A layout would still have good supersonic performance, but also have reasonable take-off and landing speeds using vortex generation. The aircraft would have to take off and land very "nose high" to generate the required vortex lift , which led to questions about the low speed handling qualities of such a design. Küchemann presented the idea at a meeting where Morgan was also present. Test pilot Eric Brown recalls Morgan's reaction to

2520-485: A mode of transport does not typically lead to such technological investments to increase the speed. Instead, the service providers prefer to compete in service quality and cost. An example of this phenomenon is high-speed rail . The speed limit of rail transport had been pushed so hard to enable it to effectively compete with road and air transport. But this achievement was not done for different rail operating companies to compete among themselves. This phenomenon also reduces

2660-588: A much stronger (and therefore heavier) structure because their fuselage must be pressurized to a greater differential than subsonic aircraft, which do not operate at the high altitudes necessary for supersonic flight. These factors together meant that the empty weight per seat of Concorde is more than three times that of a Boeing 747. Concorde and the TU-144 were both constructed of conventional aluminum: Concorde of Hiduminium and TU-144 of duralumin . Modern, advanced materials were not to come out of development for

2800-567: A negative view, suggesting that there was no way the project would have any positive financial returns for the government, especially in light that "the industry's past record of over-optimistic estimating (including the recent history of the TSR.2) suggests that it would be prudent to consider" the cost "to turn out much too low." This led to an independent review of the project by the Committee on Civil Scientific Research and Development, which met on

2940-679: A particular route. This would remain economically advantageous as long as fuel represented a small percentage of operational costs. STAC suggested that two designs naturally fell out of their work, a transatlantic model flying at about Mach 2, and a shorter-range version flying at Mach 1.2. Morgan suggested that a 150-passenger transatlantic SST would cost about £75 to £90 million to develop, and be in service in 1970. The smaller 100-passenger short-range version would cost perhaps £50 to £80 million, and be ready for service in 1968. To meet this schedule, development would need to begin in 1960, with production contracts let in 1962. Morgan suggested that

SECTION 20

#1732772998559

3080-642: A perceived slight by de Gaulle. At the French roll-out in Toulouse in late 1967, the British Minister of Technology , Tony Benn , announced that he would change the spelling back to Concorde . This created a nationalist uproar that died down when Benn stated that the suffixed "e" represented "Excellence, England, Europe, and Entente (Cordiale) ". In his memoirs, he recounted a letter from a Scotsman claiming, "you talk about 'E' for England, but part of it

3220-445: A predominantly blue livery, with the exception of the wings, in a promotional deal with Pepsi . In this paint scheme, Air France was advised to remain at Mach 2 (2,120 km/h; 1,320 mph) for no more than 20 minutes at a time, but there was no restriction at speeds under Mach 1.7. F-BTSD was used because it was not scheduled for any long flights that required extended Mach 2 operations. Supersonic airliner Following

3360-698: A researcher in ballistics . Her work involved tedious mathematical computations using the Brunsviga mechanical calculators. In 1939, Weber joined the Aerodynamics Research Institute ( Aerodynamische Versuchsanstalt Göttingen ) in Göttingen . She was part of a small theoretical team, and her initial training in aerodynamics consisted of wind tunnel corrections. Here she met and began her lifelong collaboration with Dietrich Küchemann . Scientists at Institute had by then worked out

3500-522: A second flight from Edinburgh , and a third which had taken off from Heathrow on a loop flight over the Bay of Biscay . By the end of the 20th century, projects like the Tupolev Tu-244 , Tupolev Tu-344 , SAI Quiet Supersonic Transport , Sukhoi-Gulfstream S-21 , High Speed Civil Transport , etc. had not been realized. For all vehicles traveling through air, the force of drag is proportional to

3640-484: A serious issue due to the high altitudes at which the planes flew, but experiments in the mid-1960s such as the controversial Oklahoma City sonic boom tests and studies of the USAF 's North American XB-70 Valkyrie proved otherwise (see Sonic boom § Abatement ). By 1964, whether civilian supersonic aircraft would be licensed was unclear, because of the problem. The annoyance of a sonic boom can be avoided by waiting until

3780-528: A similar aircraft after considering the SST problem and coming to the same conclusions as the Bristol and STAC teams in terms of economics. It was later revealed that the original STAC report, marked "For UK Eyes Only", had secretly been passed to France to win political favour. Sud made minor changes to the paper and presented it as their own work. France had no modern large jet engines and had already decided to buy

3920-620: A single return trip could be made per day, so the extra speed was not an advantage to the airline other than as a selling feature to its customers. The proposed American SSTs were intended to fly at Mach 3, partly for this reason. However, allowing for acceleration and deceleration time, a trans-Atlantic trip on a Mach 3 SST would be less than three times as fast as a Mach 1 trip. Since SSTs produce sonic booms at supersonic speeds they are rarely permitted to fly supersonic over land, and must fly supersonic over sea instead. Since they are inefficient at subsonic speeds compared to subsonic aircraft, range

4060-424: A speed increase. Also, for-profit companies generally prefer low risk business plans with high probabilities of appreciable profit, but an expensive leading-edge technological research and development program is a high-risk enterprise, as it is possible that the program will fail for unforeseeable technical reasons or will meet cost overruns so great as to force the company, due to financial resource limits, to abandon

4200-435: A supersonic aircraft needs to change with its speed for optimal performance. Thus, an SST would ideally change shape during flight to maintain optimal performance at both subsonic and supersonic speeds. Such a design would introduce complexity which increases maintenance needs, operations costs, and safety concerns. In practice all supersonic transports have used essentially the same shape for subsonic and supersonic flight, and

4340-571: A thin delta wing with a high angle of attack could generate sufficient lift to provide the take-off and landing capability, while simultaneously enabling efficient supersonic performance. Küchemann then advocated this wing configuration with the UK Government, resulting in the support for a Mach 2 airliner by the Supersonic Transport Advisory Committee (STAC) in 1956. In 1961, a prototype aircraft,

Concorde - Misplaced Pages Continue

4480-534: A threat that was, in 1974, seemingly validated by an MIT team commissioned by the United States Department of Transportation . However, while many purely theoretical models were indicating the potential for large ozone losses from SST nitrogen oxides ( NOx ), other scientists in the paper " Nitrogen Oxides, Nuclear Weapon Testing , Concorde and Stratospheric Ozone " turned to historical ozone monitoring and atmospheric nuclear testing to serve as

4620-524: A turbojet's noise could be reduced and SNECMA made advances in silencer design during the programme. The Olympus Mk.622 with reduced jet velocity was proposed to reduce the noise but was not pursued. By 1974, the spade silencers which projected into the exhaust were reported to be ineffective but "entry-into-service aircraft are likely to meet their noise guarantees". The powerplant configuration selected for Concorde highlighted airfield noise, boundary layer management and interactions between adjacent engines and

4760-407: A twin-engined aircraft above Mach 1.6". Situated behind the wing leading edge, the engine intake had a wing boundary layer ahead of it. Two-thirds were diverted and the remaining third which entered the intake did not adversely affect the intake efficiency except during pushovers when the boundary layer thickened and caused surging. Wind tunnel testing helped define leading-edge modifications ahead of

4900-454: A typical wing design will cut its L/D ratio in half (e.g., Concorde managed a ratio of 7.14, whereas the subsonic Boeing 747 has an L/D ratio of 17). Because an aircraft's design must provide enough lift to overcome its own weight, a reduction of its L/D ratio at supersonic speeds requires additional thrust to maintain its airspeed and altitude. Jet engine design shifts significantly between supersonic and subsonic aircraft. Jet engines, as

5040-409: A unit cost of £23 million in 1977 (equivalent to £180.49 million in 2023). Its sonic boom made travelling supersonically over land impossible without causing complaints from citizens. World events also dampened Concorde sales prospects; the 1973–74 stock market crash and the 1973 oil crisis had made airlines cautious about aircraft with high fuel consumption, and new wide-body aircraft , such as

5180-638: A vice president with Lockheed , stated to various magazines that an SST constructed of steel weighing 250,000 pounds (110,000 kg) could be developed for $ 160 million and in production lots of 200 or more sold for around $ 9 million. But it was the Anglo-French development of the Concorde that set off panic in the US industry, where it was thought that Concorde would soon replace all other long range designs, especially after Pan Am took out purchase options on

5320-404: A visor was used to keep high temperature air from flowing over the cockpit skin. Concorde had livery restrictions; the majority of the surface had to be covered with a highly reflective white paint to avoid overheating the aluminium structure due to heating effects. The white finish reduced the skin temperature by 6 to 11 °C (11 to 20 °F). In 1996, Air France briefly painted F-BTSD in

5460-578: A year later to the University of Göttingen . She graduated with a first class honours degree in 1935, and then trained as a teacher for two years. As she did not join the Nazi Party , she was not allowed to join a teaching post. Her remaining family, comprising her mother and sister, were in need of financial support, so she sought employment in the armaments industry. Weber joined Krupp in Essen as

5600-421: Is a function of forward speed, which decreases from propellers, to fans, to no bypass at all as speed increases. Additionally, the large frontal area taken up by the low-pressure fan at the front of the engine increases drag, especially at supersonic speeds, and means the bypass ratios are much more limited than on subsonic aircraft. For example, the early Tu-144S was fitted with a low bypass turbofan engine which

5740-442: Is deteriorated and the number of routes that the aircraft can fly non-stop is reduced. This also reduces the desirability of such aircraft for most airlines. Supersonic aircraft have higher per-passenger fuel consumption than subsonic aircraft; this makes the ticket price necessarily higher, all other factors being equal, as well as making that price more sensitive to the price of oil. (It also makes supersonic flights less friendly to

Concorde - Misplaced Pages Continue

5880-403: Is low at take-off, but is forced high during supersonic cruise. Transition between the two modes would occur at some point during the climb and back again during the descent (to minimize jet noise upon approach). The difficulty is devising a variable cycle engine configuration that meets the requirement for a low cross-sectional area during supersonic cruise. The sonic boom was not thought to be

6020-550: Is made in Scotland." Given Scotland's contribution of providing the nose cone for the aircraft, Benn replied, "it was also 'E' for 'Écosse' (the French name for Scotland) – and I might have added 'e' for extravagance and 'e' for escalation as well!" In common usage in the United Kingdom, the type is known as "Concorde" without an article , rather than " the Concorde" or " a Concorde". Advertisements for Concorde during

6160-433: Is more efficient, it is still less efficient than flying subsonically. Another issue in supersonic flight is the lift to drag ratio (L/D ratio) of the wings. At supersonic speeds, airfoils generate lift in an entirely different manner than at subsonic speeds, and are invariably less efficient. For this reason, considerable research has been put into designing wing planforms for sustained supersonic cruise. At about Mach 2,

6300-491: Is not able to withstand temperatures much over 127 °C; above 127 °C the aluminium gradually loses its properties that were brought about by age hardening. For aircraft that have flown at Mach 3, materials such as stainless steel ( XB-70 Valkyrie , MiG-25 ) or titanium ( SR-71 , Sukhoi T-4 ) have been used. The range of an aircraft depends on three efficiencies which appear in the Breguet range equation. They are

6440-403: Is not generated the same way at supersonic and subsonic speeds, with the lift-to-drag ratio for supersonic designs being about half that of subsonic designs. The aircraft would need more thrust than a subsonic design of the same size. But although they would use more fuel in cruise, they would be able to fly more revenue-earning flights in a given time, so fewer aircraft would be needed to service

6580-431: The Boeing 707 or de Havilland Comet , it would have been much more competitive, though the 707 and DC-8 still carried more passengers. When these high bypass jet engines reached commercial service in the 1960s, subsonic jet engines immediately became much more efficient, closer to the efficiency of turbojets at supersonic speeds. One major advantage of the SST disappeared. Turbofan engines improve efficiency by increasing

6720-413: The Boeing 747 carrying four times that, the speed and fuel advantages of the SST concept were taken away by sheer size. Another problem was that the wide range of speeds over which an SST operates makes it difficult to improve engines. While subsonic engines had made great strides in increased efficiency through the 1960s with the introduction of the turbofan engine with ever-increasing bypass ratios ,

6860-606: The Boeing 747 , had recently made subsonic aircraft significantly more efficient and presented a low-risk option for airlines. While carrying a full load, Concorde achieved 15.8 passenger miles per gallon of fuel, while the Boeing 707 reached 33.3 pm/g, the Boeing 747 46.4 pm/g, and the McDonnell Douglas DC-10 53.6 pm/g. A trend in favour of cheaper airline tickets also caused airlines such as Qantas to question Concorde's market suitability. During

7000-468: The Handley Page HP.115 , was built to test the low speed performance of the slender delta wing. Weber made two fundamental contributions to the supersonic effort: tools to predict the drag on a slender delta-winged aircraft during supersonic flight, and shaping the wing to allow the formation of vortices at its leading edge, rather than above or below it. Her work from 1959 onwards contributed to

7140-475: The National Oceanic and Atmospheric Administration , and others, suggest that the drop in ozone would be at most, "no more" than 1 to 2% if a fleet of 500 supersonic aircraft [were] operated. Fahey expressed that this would not be a fatal obstacle for an advanced SST development – while "a big caution flag...[it] should not be a showstopper for advanced SST development" because "removing the sulfur in

SECTION 50

#1732772998559

7280-560: The Tu-144 , which the western press nicknamed the "Concordski". The SST was seen as particularly offensive due to its sonic boom and the potential for its engine exhaust to damage the ozone layer . Both problems impacted the thinking of lawmakers, and eventually Congress dropped funding for the US SST program in March 1971, and all overland commercial supersonic flight was banned over

7420-607: The Tupolev Tu-144 . Concorde was the first airliner to have a fly-by-wire flight-control system (in this case, analogue); the avionics system Concorde used was unique because it was the first commercial aircraft to employ hybrid circuits . The principal designer for the project was Pierre Satre, with Sir Archibald Russell as his deputy. Concorde pioneered the following technologies: For high speed and optimisation of flight: For weight-saving and enhanced performance: A symposium titled "Supersonic-Transport Implications"

7560-409: The coefficient of drag ( C d ), to the square of the airspeed and to the air density. Since drag rises rapidly with speed, a key priority of supersonic aircraft design is to minimize this force by lowering the coefficient of drag. This gives rise to the highly streamlined shapes of SSTs. To some extent, supersonic aircraft also manage drag by flying at higher altitudes than subsonic aircraft, where

7700-548: The delta wing in most studies, including the Sud Aviation Super-Caravelle and Bristol Type 223 , although Armstrong-Whitworth proposed a more radical design, the Mach 1.2 M-Wing . Avro Canada proposed several designs to TWA that included Mach 1.6 double-ogee wing and Mach 1.2 delta-wing with separate tail and four under-wing engine configurations. Avro's team moved to the UK where its design formed

7840-422: The transonic speed range, between Mach 0.95 and 1.7. Kinetic heating from the high speed boundary layer caused the skin to heat up during supersonic flight. Every surface, such as windows and panels, was warm to the touch by the end of the flight. Apart from the engine bay, the hottest part of any supersonic aircraft's structure is the nose , due to aerodynamic heating . Hiduminium R.R. 58, an aluminium alloy,

7980-567: The 1950s, she developed a simultaneous treatment of all the features of a wing (thickness, twist, sweepback, camber) to predict the air pressure distribution over it. The Vickers aircraft team then solved the inverse problem - that of determining the wing shape that best suited a required pressure distribution. The resultant wing shape, the most advanced for a civilian craft, was used on the Vickers VC10 airliner. Weber also began her research into supersonic transport. In 1955, she showed that

8120-481: The Americans. Everyone involved agreed that Küchemann's ogee-shaped wing was the right one. The British team was still focused on a 150-passenger design serving transatlantic routes, while France was deliberately avoiding these. Common components could be used in both designs, with the shorter range version using a clipped fuselage and four engines, and the longer one a stretched fuselage and six engines, leaving only

8260-421: The Concorde. Congress was soon funding an SST design effort, selecting the existing Lockheed L-2000 and Boeing 2707 designs, to produce an even more advanced, larger, faster and longer ranged design. The Boeing 2707 design was eventually selected for continued work, with design goals of ferrying around 300 passengers and having a cruising speed near to Mach 3 . The Soviet Union set out to produce its own design,

8400-541: The London–New York route in mind. The plane was allowed into Washington, D.C. (at Dulles in Virginia ), and the service was so popular that New Yorkers were soon complaining because they did not have it. It was not long before Concorde was flying into JFK . Along with shifting political considerations, the flying public continued to show interest in high-speed ocean crossings. This started additional design studies in

8540-463: The M-Wing, for the lower-speed shorter-range category. Both the STAC group and the government were looking for partners to develop the designs. In September 1959, Hawker approached Lockheed , and after the creation of British Aircraft Corporation in 1960, the former Bristol team immediately started talks with Boeing , General Dynamics , Douglas Aircraft , and Sud Aviation . Küchemann and others at

SECTION 60

#1732772998559

8680-595: The RAE as a consultant. She had nearly 100 papers to her name. In 1976, following Küchemann's death, Weber assisted in the publication of his book The Aerodynamic Design of Aircraft , which was published in 1978. She announced that she was done with aerodynamics after that. Weber remained unmarried all her life. She lived in the RAE hostel until 1953, and then moved into a bedsit attached to Küchemann's house in Wrecclesham, Surrey, where she lived till 1961, when she acquired

8820-495: The RAE continued their work on the slender delta throughout this period, considering three basic shapes; the classic straight-edge delta, the "gothic delta" that was rounded outward to appear like a gothic arch , and the " ogival wing" that was compound-rounded into the shape of an ogee . Each of these planforms had advantages and disadvantages. As they worked with these shapes, a practical concern grew to become so important that it forced selection of one of these designs. Generally

8960-425: The SST fleet would emit ~96 million metric tons of CO₂ per year (like American , Delta and Southwest combined in 2017), 1.6 to 2.4 gigatonnes of CO₂ over their 25-year lifetime: one-fifth of the international aviation carbon budget if aviation maintains its emissions share to stay under a 1.5 °C climate trajectory . Noise exposed area around airports could double compared to existing subsonic aircraft of

9100-673: The UK as part of the combined US-UK plan ( Operation Paperclip and Operation Surgeon ) to acquire German services and technologies. In October 1946, Küchemann joined the Aerodynamics department at the Royal Aircraft Establishment in Farnbourough, and persuaded Weber to join him. Both of them continued to renew their six-month contracts, although both remained classed as enemy aliens , until 1953 when both were naturalised as British citizens. Weber, as

9240-474: The US was already involved in a similar project, and that if the UK failed to respond it would be locked out of an airliner market that he believed would be dominated by SST aircraft. In 1959, a study contract was awarded to Hawker Siddeley and Bristol for preliminary designs based on the slender delta, which developed as the HSA.1000 and Bristol 198 . Armstrong Whitworth also responded with an internal design,

9380-470: The US, under the name "AST" (Advanced Supersonic Transport). Lockheed's SCV was a new design for this category, while Boeing continued studies with the 2707 as a baseline. By this time, the economics of past SST concepts were no longer reasonable. When first designed, the SSTs were envisioned to compete with long-range aircraft seating 80 to 100 passengers such as the Boeing 707 , but with newer aircraft such as

9520-415: The US. Presidential advisor Russell Train warned that a fleet of 500 SSTs flying at 65,000 ft (20 km) for a period of years could raise stratospheric water content by as much as 50% to 100%. According to Train, this could lead to greater ground-level heat and hamper the formation of ozone . Later, an additional threat to the ozone was hypothesized as a result of the exhaust's nitrogen oxides ,

9660-405: The aerodynamic efficiency, which says how much wanted lift can be produced without too much unwanted drag, powerplant efficiency, which says how much fuel is converted into moving the aircraft against its drag resistance, and structural efficiency, which says how heavy the structure is compared to the fuel and passengers it can carry. Airlines potentially value very fast aircraft, because it enables

9800-475: The aerodynamic requirement for a narrow fuselage make SSTs an expensive form of commercial civil transportation compared with subsonic aircraft. For example, the Boeing 747 can carry more than three times as many passengers as Concorde while using approximately the same amount of fuel. Nevertheless, fuel costs are not the bulk of the price for most subsonic aircraft passenger tickets. For the transatlantic business market that SST aircraft were utilized for, Concorde

9940-591: The air density is lower. As speeds approach the speed of sound, the additional phenomenon of wave drag appears. This is a powerful form of drag that begins at transonic speeds (around Mach 0.88 ). Around Mach 1, the peak coefficient of drag is four times that of subsonic drag. Above the transonic range, the coefficient drops drastically again, although remains 20% higher by Mach 2.5 than at subsonic speeds. Supersonic aircraft must have considerably more power than subsonic aircraft require to overcome this wave drag, and although cruising performance above transonic speed

10080-477: The aircraft at Mach 2 without difficulties. During an engine failure the required air intake is virtually zero. So, on Concorde, engine failure was countered by the opening of the auxiliary spill door and the full extension of the ramps, which deflected the air downwards past the engine, gaining lift and minimising drag. Concorde pilots were routinely trained to handle double-engine failure. speeds Concorde used reheat (afterburners) only at take-off and to pass through

10220-644: The aircraft is at high altitude over water before reaching supersonic speeds; this was the technique used by Concorde. However, it precludes supersonic flight over populated areas. Supersonic aircraft have poor lift/drag ratios at subsonic speeds as compared to subsonic aircraft (unless technologies such as variable-sweep wings are employed), and hence burn more fuel, which results in their use being economically disadvantageous on such flight paths. Concorde had an overpressure of 1.94 lb/sq ft (93 Pa) (133 dBA SPL). Overpressures over 1.5 lb/sq ft (72 Pa) (131 dBA SPL) often cause complaints. If

10360-405: The aircraft lose thrust on that side but the engine creates drag, causing the aircraft to yaw and bank in the direction of the failed engine. If this had happened to Concorde at supersonic speeds, it theoretically could have caused a catastrophic failure of the airframe. Although computer simulations predicted considerable problems, in practice Concorde could shut down both engines on the same side of

10500-502: The aircraft spends a considerable amount of time in cruise. SST designs flying at least three times as fast as existing subsonic transports were possible, and would thus be able to replace as many as three planes in service, and thereby lower costs in terms of manpower and maintenance. Serious work on SST designs started in the mid-1950s, when the first generation of supersonic fighter aircraft were entering service. In Britain and France, government-subsidized SST programs quickly settled on

10640-495: The aircraft to make more flights per day, providing a higher return on investment. Also, passengers generally prefer faster, shorter-duration trips to slower, longer-duration trips, so operating faster aircraft can give an airline a competitive advantage, even to the extent that many customers will willingly pay higher fares for the benefit of saving time and/or arriving sooner. However, Concorde's high noise levels around airports, time zone issues, and insufficient speed meant that only

10780-413: The airline desirability of SSTs, because, for very long-distance transportation (a couple of thousand kilometers), competition between different modes of transport is rather like a single-horse race: air transport does not have a significant competitor. The only competition is between the airline companies, and they would rather pay moderately to reduce cost and increase service quality than pay much more for

10920-410: The airport's opening. Concorde had initially held a great deal of customer interest, but the project was hit by order cancellations. The Paris Le Bourget air show crash of the competing Soviet Tupolev Tu-144 had shocked potential buyers, and public concern over the environmental issues of supersonic aircraft – the sonic boom , take-off noise and pollution – had produced

11060-408: The amount of cold low-pressure air they accelerate, using some of the energy normally used to accelerate hot air in the classic non-bypass turbojet. The ultimate expression of this design is the turboprop , where almost all of the jet thrust is used to power a very large fan – the propeller . The efficiency curve of the fan design means that the amount of bypass that maximizes overall engine efficiency

11200-572: The basis of Hawker Siddeley 's designs. By the early 1960s, the designs had progressed to the point where the go-ahead for production was given, but costs were so high that the Bristol Aeroplane Company and Sud Aviation eventually merged their efforts in 1962 to produce Concorde. In the early 1960s, various executives of US aerospace companies were telling the US public and Congress that there were no technical reasons an SST could not be produced. In April 1960, Burt C Monesmith,

11340-601: The capability of reducing the boom by about half. Even lengthening the vehicle (without significantly increasing the weight) would seem to reduce the boom intensity (see Sonic boom § Abatement ). When it comes to public policy, for example, the FAA prohibits commercial airplanes from flying at supersonic speeds above sovereign land governed by the United States because of the negative impact the sonic boom brings to humans and animal populations below. The aerodynamic design of

11480-555: The chief sources of aerodynamic inefficiency was the junction of the wing and the fuselage, and she was able to model its entire three-dimensional profile. These methods, along with others evolving from the development of the VC10, were used in the design of the Airbus A300B aircraft, the first wide-body twinjet in the world. Weber retired in 1975 at the grade of Senior Principal Scientific Officer, and continued to be retained by

11620-462: The design and the eventual construction of the Concorde . Weber reverted to subsonic researches following the Concorde. In particular, she analysed the conditions under which methods addressing airflows slower than the speed of sound continued to be applicable at supercritical levels. Her refinement of existing theories, which were based on incompressible flows, helped automate the computations to render exact, rather than approximate, solutions. One of

11760-609: The development of the Handley Page Victor bomber and the Concorde . Johanna Weber was born in a family of Walloon origin in Düsseldorf , Germany , on August 8, 1910. Her father died in the First World War . As a 'war orphan', Weber was eligible for financial support, and she attended a convent school. In 1929, she began studies in chemistry and mathematics at the University of Cologne , but switched

11900-565: The development teams met, the French Minister of Public Works and Transport Robert Buron was meeting with the UK Minister of Aviation Peter Thorneycroft , and Thorneycroft told the cabinet that France was much more serious about a partnership than any of the US companies. The various US companies had proved uninterested, likely due to the belief that the government would be funding development and would frown on any partnership with

12040-702: The direction of their research based on his consultation with manufacturers. Over the period of the Second World War , they created a substantial body of work. Following the capture of Göttingen by the US Army in 1945, the city fell into the British occupation zone. The British paid Weber and Küchemann to compile a monograph of their researches. These would form the basis of their text Aerodynamics of Propulsion . They also encouraged German scientists to take up six month contracts at various defence facilities in

12180-425: The distance. Delays and cost overruns increased the programme cost to £1.5–2.1 billion in 1976, (£11–16 billion in 2023). Concorde entered service on 21 January 1976 with Air France from Paris-Roissy and British Airways from London Heathrow . Transatlantic flights were the main market, to Washington Dulles from 24 May, and to New York JFK from 17 October 1977. Air France and British Airways remained

12320-671: The early 2000s, Flight International described Concorde as being "one of aerospace's most ambitious but commercially flawed projects", The consortium received orders (non-binding options) for more than 100 of the long-range version from the major airlines of the day: Pan Am , BOAC , and Air France were the launch customers, with six aircraft each. Other airlines in the order book included Panair do Brasil , Continental Airlines , Japan Airlines , Lufthansa , American Airlines , United Airlines , Air India , Air Canada , Braniff , Singapore Airlines , Iran Air , Olympic Airways , Qantas , CAAC Airlines , Middle East Airlines , and TWA . At

12460-742: The effort before it yields any marketable SST technology, causing potentially all investment to be lost. The International Council on Clean Transportation (ICCT) estimates a SST would burn 5 to 7 times as much fuel per passenger. The ICCT shows that a New York to London supersonic flight would consume more than twice as much fuel per passenger than in subsonic business-class , six times as much as for economy class , and three times as much as subsonic business for Los Angeles to Sydney. Designers can either meet existing environmental standards with advanced technology or lobby policymakers to establish new standards for SSTs. If there were 2,000 SSTs in 2035, there would be 5,000 flights per day at 160 airports and

12600-453: The engine air inputs based on the work she had done with Küchemann during the war. Her linear and simple aerodynamic models were calculated by hand by a team of women 'computors'. In September 1945, she co-wrote with Küchemann a paper analysing the aerodynamics of the new wing and fuselage. Weber's subsequent work with Küchemann was in improving the theory of subsonic aerodynamics. Initial methods treated wing thickness and lift in isolation. In

12740-407: The entire nature of supersonic design. The delta had already been used on aircraft, but these designs used planforms that were not much different from a swept wing of the same span. Weber noted that the lift from the vortex was increased by the length of the wing it had to operate over, which suggested that the effect would be maximised by extending the wing along the fuselage as far as possible. Such

12880-461: The environment and sustainability, two growing concerns of the general public, including air travelers.) Investing in research and development work to design a new SST can be considered as an effort to push the speed limit of air transport. Generally, other than an urge for new technological achievement, the major driving force for such an effort is competitive pressure from other modes of transport. Competition between different service providers within

13020-461: The fact that delta wings can produce strong vortices on their upper surfaces at high angles of attack . The vortex will lower the air pressure and cause lift. This had been noticed by Chuck Yeager in the Convair XF-92 , but its qualities had not been fully appreciated. Weber suggested that the effect could be used to improve low speed performance. Küchemann's and Weber's papers changed

13160-454: The fan concept is difficult to use at supersonic speeds where the "proper" bypass is about 0.45, as opposed to 2.0 or higher for subsonic designs. For both of these reasons the SST designs were doomed by higher operational costs, and the AST programs vanished by the early 1980s. Concorde only sold to British Airways and Air France, with subsidized purchases that were to return 80% of the profits to

13300-532: The first meeting, on 5 November 1956, the decision was made to fund the development of a test-bed aircraft to examine the low-speed performance of the slender delta, a contract that eventually produced the Handley Page HP.115 . This aircraft demonstrated safe control at speeds as low as 69 mph (111 km/h), about one third that of the F-104 Starfighter. STAC stated that an SST would have economic performance similar to existing subsonic types. Lift

13440-417: The flight deck between the flight engineer 's console and the bulkhead. On some aircraft that conducted a retiring supersonic flight, the flight engineers placed their caps in this expanded gap, wedging the cap when the airframe shrank again. To keep the cabin cool, Concorde used the fuel as a heat sink for the heat from the air conditioning. The same method also cooled the hydraulics. During supersonic flight

13580-441: The fuel of the [Concorde]" would essentially eliminate the hypothesized 1%–2% ozone-destruction-reaction-pathway. Despite the model-observation discrepancy surrounding the ozone concern, in the mid-1970s, six years after its first supersonic test flight, Concorde was now ready for service. The US political outcry was so high that New York banned the plane. This threatened the aircraft's economic prospects — it had been built with

13720-424: The government. In practice for almost all of the length of the arrangement, there was no profit to be shared. After Concorde was privatized, cost reduction measures (notably the closing of the metallurgical wing testing site which had done enough temperature cycles to validate the aircraft through to 2010) and ticket price raises led to substantial profits. Since Concorde stopped flying, it has been revealed that over

13860-446: The ground killed. This was the only fatal incident involving Concorde; commercial service was suspended until November 2001. The surviving aircraft were retired in 2003, 27 years after commercial operations had begun. All but 2 of the 20 aircraft built have been preserved and are on display across Europe and North America. In the early 1950s, Arnold Hall , director of the Royal Aircraft Establishment (RAE), asked Morien Morgan to form

14000-510: The group considered the concept of an SST infeasible, and instead suggested continued low-level studies into supersonic aerodynamics. Soon after, Johanna Weber and Dietrich Küchemann at the RAE published a series of reports on a new wing planform , known in the UK as the "slender delta". The team, including Eric Maskell whose report "Flow Separation in Three Dimensions" contributed to an understanding of separated flow, worked with

14140-598: The house next door to the Küchemanns. She found it difficult to obtain a mortgage , as banks and building societies tended not to lend to single women for home purchases at the time. After retirement, Weber discovered new interests in psychology and geology, taking classes at the University of Surrey . Weber's younger sister, to whom she was very close, had been in poor health for most of her life. Weber supported her and their mother financially, sending money to Germany, and wanted to return to them. Her sister died at

14280-557: The increased space required for such a feature produced capacity problems that proved ultimately insurmountable. North American Aviation had an unusual approach to this problem with the XB-70 Valkyrie . By lowering the outer panels of the wings at high Mach numbers, they were able to take advantage of compression lift on the underside of the aircraft. This improved the L/D ratio by about 30%. Aircraft are surrounded by an air layer

14420-1003: The intakes which solved the problem. Each engine had its own intake and the nacelles were paired with a splitter plate between them to minimise the chance of one powerplant influencing the other. Only above Mach 1.6 (1,960 km/h; 1,220 mph) was an engine surge likely to affect the adjacent engine. The air intake design for Concorde's engines was especially critical. The intakes had to slow down supersonic inlet air to subsonic speeds with high-pressure recovery to ensure efficient operation at cruising speed while providing low distortion levels (to prevent engine surge) and maintaining high efficiency for all likely ambient temperatures in cruise. They had to provide adequate subsonic performance for diversion cruise and low engine-face distortion at take-off. They also had to provide an alternative path for excess intake of air during engine throttling or shutdowns. The variable intake features required to meet all these requirements consisted of front and rear ramps,

14560-407: The intensity of the boom can be reduced, then this may make even very large designs of supersonic aircraft acceptable for overland flight. Research suggests that changes to the nose cone and tail can reduce the intensity of the sonic boom below that needed to cause complaints. During the original SST efforts in the 1960s, it was suggested that careful shaping of the fuselage of the aircraft could reduce

14700-422: The intensity of the sonic boom's shock waves that reach the ground. One design caused the shock waves to interfere with each other, greatly reducing the sonic boom. This was difficult to test at the time, but the increasing power of computer-aided design has since made this considerably easier. In 2003, a Shaped Sonic Boom Demonstration aircraft was flown which proved the soundness of the design and demonstrated

14840-421: The late 1960s placed in publications such as Aviation Week & Space Technology predicted a market for 350 aircraft by 1980. The new consortium intended to produce one long-range and one short-range version, but prospective customers showed no interest in the short-range version, thus it was later dropped. Concorde's costs spiralled during development to more than six times the original projections, arriving at

14980-617: The life of Concorde, the plane did prove profitable, at least to British Airways. Concorde operating costs over nearly 28 years of operation were approximately £1 billion, with revenues of £1.75 billion. On 25 July 2000, Air France Flight 4590 crashed shortly after take-off with all 109 occupants and four on ground killed; the only fatal incident involving Concorde . Commercial service was suspended until November 2001, and Concorde aircraft were retired in 2003 after 27 years of commercial operations. The last regular passenger flights landed at London Heathrow on October 24, 2003, from New York ,

15120-410: The metallurgical and fatigue modelling. A test rig was built that repeatedly heated up a full-size section of the wing, and then cooled it, and periodically samples of metal were taken for testing. The airframe was designed for a life of 45,000 flying hours. As the fuselage heated up it expanded by as much as 300 mm (12 in). The most obvious manifestation of this was a gap that opened up on

15260-410: The noise concern, although some of these restrictions were later relaxed. Professor Douglas Ross characterised restrictions placed upon Concorde operations by President Jimmy Carter 's administration as having been an act of protectionism of American aircraft manufacturers. The original programme cost estimate was £70 million in 1962, (£1.68 billion in 2023). After cost overruns and delays

15400-602: The only woman among the German scientists, was accommodated at an RAE staff hostel. She joined the Low Speed Wind Tunnels division at the RAE, which was headed by Frances Bradfield . She began experimental work on air intakes under John Seddon . In 1946, the British Air Ministry specified a medium-range jet propelled bomber capable of carrying a nuclear weapon. The Handley Page Victor bomber

15540-446: The planned Avro 730 strategic bomber that the team studied. The team outlined a baseline configuration that resembled an enlarged Avro 730. This short wingspan produced little lift at low speed, resulting in long take-off runs and high landing speeds. In an SST design, this would have required enormous engine power to lift off from existing runways and, to provide the fuel needed, "some horribly large aeroplanes" resulted. Based on this,

15680-445: The podded installation was put forward as simpler with only an inlet cone, however, Dr. Seddon of the RAE favoured a more integrated buried installation. One concern of placing two or more engines behind a single intake was that an intake failure could lead to a double or triple engine failure. While a ducted fan over the turbojet would reduce noise, its larger cross-section also incurred more drag. Acoustics specialists were confident that

15820-453: The practice. SST engines need a fairly high specific thrust (net thrust/airflow) during supersonic cruise, to minimize engine cross-sectional area and, thereby, nacelle drag. Unfortunately this implies a high jet velocity, which makes the engines noisy, particularly at low speeds/altitudes and at take-off. Therefore, a future SST might well benefit from a variable cycle engine , where the specific thrust (and therefore jet velocity and noise)

15960-699: The presentation, saying that he immediately seized on it as the solution to the SST problem. Brown considers this moment as being the birth of the Concorde project. On 1 October 1956 the Ministry of Supply asked Morgan to form a new study group, the Supersonic Transport Aircraft Committee (STAC) (sometimes referred to as the Supersonic Transport Advisory Committee), to develop a practical SST design and find industry partners to build it. At

16100-471: The programme eventually cost between £1.5 and £2.1 billion in 1976, (£11.4 billion – 16 billion in 2023). This cost was the main reason the production run was much smaller than expected. Concorde is an ogival delta winged aircraft with four Olympus engines based on those employed in the RAF's Avro Vulcan strategic bomber . It has an unusual tailless configuration for a commercial aircraft, as does

16240-492: The project would not be likely to significantly affect other, more important, research efforts. At the time, the UK was pressing for admission to the European Economic Community , and this became the main rationale for moving ahead with the aircraft. The development project was negotiated as an international treaty between the two countries rather than a commercial agreement between companies and included

16380-530: The public on 7–8 June 1969 at the Paris Air Show . As the flight programme progressed, 001 embarked on a sales and demonstration tour on 4 September 1971, which was also the first transatlantic crossing of Concorde. Concorde 002 followed on 2 June 1972 with a tour of the Middle and Far East. Concorde 002 made the first visit to the United States in 1973, landing at Dallas/Fort Worth Regional Airport to mark

16520-405: The publicity manager at BAC's Filton plant. Reflecting the treaty between the British and French governments that led to Concorde's construction, the name Concorde is from the French word concorde ( IPA: [kɔ̃kɔʁd] ), which has an English equivalent, concord . Both words mean agreement , harmony , or union . The name was changed to Concord by Harold Macmillan in response to

16660-408: The requirement that the powerplant, at Mach 2, tolerate pushovers, sideslips, pull-ups and throttle slamming without surging. Extensive development testing with design changes and changes to intake and engine control laws addressed most of the issues except airfield noise and the interaction between adjacent powerplants at speeds above Mach 1.6 which meant Concorde "had to be certified aerodynamically as

16800-566: The same size, with more than 300 operations per day at Dubai and London Heathrow , and over 100 in Los Angeles , Singapore , San Francisco , New York-JFK , Frankfurt , and Bangkok . Frequent sonic booms would be heard in Canada, Germany, Iraq, Ireland, Israel, Romania, Turkey, and parts of the United States, up to 150–200 per day or one every five minutes. On August 21, 1961, a Douglas DC-8-43 (registration N9604Z) exceeded Mach 1 in

16940-468: The simulations had been correct, and this information was added to pilot training. France had its own SST plans. In the late 1950s, the government requested designs from the government-owned Sud Aviation and Nord Aviation , as well as Dassault . All three returned designs based on Küchemann and Weber's slender delta; Nord suggested a ramjet powered design flying at Mach 3, and the other two were jet-powered Mach 2 designs that were similar to each other. Of

17080-552: The six prototypes began in February 1965, and the first flight took off from Toulouse on 2 March 1969. The market was predicted for 350 aircraft, and the manufacturers received up to 100 option orders from many major airlines . On 9 October 1975, it received its French Certificate of Airworthiness , and from the UK CAA on 5 December. Concorde is a tailless aircraft design with a narrow fuselage permitting 4-abreast seating for 92 to 128 passengers, an ogival delta wing and

17220-535: The sole customers with seven airframes each , for a total production of twenty. Supersonic flight more than halved travel times, but sonic booms over the ground limited it to transoceanic flights only. Its only competitor was the Tupolev Tu-144 , carrying passengers from November 1977 until a May 1978 crash , while a potential competitor, the Boeing 2707 , was cancelled in 1971 before any prototypes were built. On 25 July 2000, Air France Flight 4590 crashed shortly after take-off with all 109 occupants and four on

17360-591: The temperature of which increases with aircraft speed. As a result the skin of the aircraft gets hotter with increasing supersonic speeds (kinetic heating from the high speed boundary layer ). Heat from the sun also raises the skin temperature. Heat transfers into the aircraft structure which also gets hotter. By the early 1960s many investigations in the United States, Britain and France had shown equilibrium skin temperatures varying from 130 degC at Mach 2.2 to 330 degC at Mach 3. Subsonic aircraft are usually made of aluminium. However aluminium, while being light and strong,

17500-724: The termination of flying by Concorde, there have been no SSTs in commercial service. However, several companies have proposed supersonic business jet designs. Small SSTs have less environmental impact and design capability improves with continuing research which is aimed at producing an acceptable aircraft. Supersonic airliners have been the objects of numerous recent ongoing design studies. Drawbacks and design challenges are excessive noise generation (at takeoff and due to sonic booms during flight), high development costs, expensive construction materials, high fuel consumption, extremely high emissions, and an increased cost per seat over subsonic airliners. However, despite these challenges, Concorde

17640-472: The three, the Sud Aviation Super-Caravelle won the design contest with a medium-range design deliberately sized to avoid competition with transatlantic US designs they assumed were already on the drawing board. As soon as the design was complete, in April 1960, Pierre Satre , the company's technical director, was sent to Bristol to discuss a partnership. Bristol was surprised to find that the Sud team had designed

17780-429: The thrust, leading to considerably greater fuel use. This effect is pronounced at speeds close to the speed of sound, as the aircraft is using twice the thrust to travel at about the same speed. The relative effect is reduced as the aircraft accelerates to higher speeds. Offsetting this increase in fuel use was the potential to greatly increase sortie rates of the aircraft, at least on medium and long-range flights where

17920-898: The time of the first flight, the options list contained 74 options from 16 airlines: The design work was supported by a research programme studying the flight characteristics of low ratio delta wings . A supersonic Fairey Delta 2 was modified to carry the ogee planform, and, renamed as the BAC 221, used for tests of the high-speed flight envelope; the Handley Page HP.115 also provided valuable information on low-speed performance. Construction of two prototypes began in February 1965: 001, built by Aérospatiale at Toulouse, and 002, by BAC at Filton , Bristol. 001 made its first test flight from Toulouse on 2 March 1969, piloted by André Turcat , and first went supersonic on 1 October. The first UK-built Concorde flew from Filton to RAF Fairford on 9 April 1969, piloted by Brian Trubshaw . Both prototypes were presented to

18060-495: The topic between July and September 1962. The committee rejected the economic arguments, including considerations of supporting the industry made by Thorneycroft. Their report in October stated that it was unlikely there would be any direct positive economic outcome, but that the project should still be considered because everyone else was going supersonic, and they were concerned they would be locked out of future markets. It appeared

18200-428: The two that are not are F-BVFD (cn 211), parked as a spare-parts source in 1982 and scrapped in 1994, and F-BTSC (cn 203), which crashed outside Paris on July 25, 2000, killing 100 passengers, 9 crew members, and 4 people on the ground. Johanna Weber Johanna Weber (8 August 1910 – 24 October 2014) was a German -born British mathematician and aerodynamicist . She is best known for her contributions to

18340-459: The wing selection. In 1965 the NASA test aircraft successfully tested the wing, and found that it reduced landing speeds noticeably over the standard delta wing. NASA also ran simulations at Ames that showed the aircraft would exhibit a sudden change in pitch when entering ground effect. Ames test pilots later participated in a joint cooperative test with the French and British test pilots and found that

18480-464: The wing to be extensively re-designed. The teams continued to meet in 1961, and by this time it was clear that the two aircraft would be very similar in spite of different ranges and seating arrangements. A single design emerged that differed mainly in fuel load. More powerful Bristol Siddeley Olympus engines, being developed for the TSR-2 , allowed either design to be powered by only four engines. While

18620-467: The wing's centre of pressure (CP, or "lift point") should be close to the aircraft's centre of gravity (CG, or "balance point") to reduce the amount of control force required to pitch the aircraft. As the aircraft layout changes during the design phase, it is common for the CG to move fore or aft. With a normal wing design this can be addressed by moving the wing slightly fore or aft to account for this. With

18760-440: Was actually very successful, and was able to sustain a higher ticket price. Now that commercial SST aircraft have stopped flying, it has become clearer that Concorde made substantial profit for British Airways. Extreme jet velocities used during take-off caused Concorde and Tu-144s to produce significant take-off noise. Communities near the airport were affected by high engine noise levels, which prompted some regulators to disfavor

18900-545: Was already available for development to meet the design requirements. Rolls-Royce proposed developing the RB.169 to power Concorde during its initial design phase, but developing a wholly-new engine for a single aircraft would have been extremely costly, so the existing BSEL Olympus Mk 320 turbojet engine, which was already flying in the BAC TSR-2 supersonic strike bomber prototype, was chosen instead. Boundary layer management in

19040-440: Was claimed to have operated profitably. Throughout the 1950s an SST looked possible from a technical standpoint, but it was not clear if it could be made economically viable. Because of differences in lift generation, aircraft operating at supersonic speeds have approximately one-half the lift-to-drag ratio of subsonic aircraft. This implies that for any given required amount of lift, the aircraft will have to supply about twice

19180-587: Was hosted by the Royal Aeronautical Society on 8 December 1960. Various views were put forward on the likely type of powerplant for a supersonic transport, such as podded or buried installation and turbojet or ducted-fan engines. Concorde needed to fly long distances to be economically viable; this required high efficiency from the powerplant. Turbofan engines were rejected due to their larger cross-section producing excessive drag (but would be studied for future SSTs). Olympus turbojet technology

19320-645: Was much less efficient than Concorde's turbojets in supersonic flight. The later TU-144D featured turbojet engines with comparable efficiency. These limitations meant that SST designs were not able to take advantage of the dramatic improvements in fuel economy that high bypass engines brought to the subsonic market, but they were already more efficient than their subsonic turbofan counterparts. Supersonic vehicle speeds demand narrower wing and fuselage designs, and are subject to greater stresses and temperatures. This leads to aeroelasticity problems, which require heavier structures to minimize unwanted flexing. SSTs also require

19460-401: Was the most ambitious of the designs proposed in response. Küchemann had kept abreast of German work into swept-wing aircraft, in particular the crescent-shaped wing, and the aerodynamics of supersonic flight. The Victor would have three segmented wings of crescent shape, each with a different sweep angle. Weber assisted with the calculations, and incorporated further design improvements including

19600-551: Was used throughout the aircraft because it was relatively cheap and easy to work with. The highest temperature it could sustain over the life of the aircraft was 127 °C (261 °F), which limited the top speed to Mach 2.02. Concorde went through two cycles of cooling and heating during a flight, first cooling down as it gained altitude at subsonic speed, then heating up accelerating to cruise speed, finally cooling again when descending and slowing down before heating again in low altitude air before landing. This had to be factored into

#558441