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Concorde

2007 Schools Wikipedia Selection. Related subjects: Air & Sea transport

                       Concorde

                             Air France Concorde

   Type          Supersonic airliner
   Manufacturer  Aérospatiale- BAC
   Maiden flight 2 March 1969
   Introduced    21 January 1976
   Retired       26 November 2003
   Primary users British Airways
                 Air France
   Number built  20
   Unit cost     £23 million (US$46 million) in 1977

   The Aérospatiale- BAC Concorde supersonic transport (SST), along with
   the Tupolev Tu-144, was one of only two models of supersonic passenger
   airliners to have seen commercial service. First flown in 1976,
   Concorde service commenced in 2003. It regularly flew from London
   Heathrow ( British Airways) and Paris Charles de Gaulle ( Air France)
   to New York JFK. However, it never fully recovered from its only crash
   in 2000, and, for economic reasons post 9/11, operations ceased in
   2003. Its development represented a major economic loss for the French
   and British governments, although it made large operating profits for
   British Airways for much of its service life. In retirement, Concorde
   remains an icon of aircraft history.

General features

   Concorde had an average cruise speed of Mach 2.02 (an airspeed of
   around 2140 km/h or 1,330 mph) with a maximum cruise altitude of 60,000
   feet (18 300 metres). It was an ogival delta-winged aircraft with four
   Olympus engines originally developed for the Avro Vulcan strategic
   bomber. The engines were jointly built by Rolls-Royce and SNECMA, the
   latter gaining its first foothold in civil aviation turbojet engine
   manufacturing. Concorde was the first civil airliner to be equipped
   with an analogue fly-by-wire flight control system. It employed a
   trademark droop snoot lowering nose section for visibility on approach
   and sported taxi and landing lights that retracted flush to its body to
   reduce drag. Commercial flights operated by British Airways and Air
   France began on 21 January 1976 and ended on 24 October 2003, with the
   last "retirement" flight on 26 November that year.

   In regular service, Concorde employed a relatively efficient
   cruise-climb. As aircraft lose weight from consuming fuel, they can fly
   at progressively higher altitudes. This is (generally) more efficient,
   so conventional airliners employ a stepped climb, where air traffic
   control will approve a change to a higher flight level as the flight
   progresses. With no other civil traffic operating at her cruise
   altitude, dedicated Oceanic airways across the Atlantic were allocated
   in which Concorde would be cleared in a 10,000' block, allowing her to
   slowly climb from 50,000 to 60,000 feet during her crossing.

Design and development

   Concorde's final flight, G-BOAF from Heathrow to Bristol, on 26
   November 2003.
   Enlarge
   Concorde's final flight, G-BOAF from Heathrow to Bristol, on 26
   November 2003.

   In the late 1950s, the United Kingdom, France, United States and Soviet
   Union were considering developing supersonic transport.
   Concorde G-BOAD on a barge beneath Verrazano Narrows Bridge in New York
   City in November 2003, bound for the Intrepid Sea-Air-Space Museum.
   Enlarge
   Concorde G-BOAD on a barge beneath Verrazano Narrows Bridge in New York
   City in November 2003, bound for the Intrepid Sea-Air-Space Museum.

   Britain's Bristol Aeroplane Company and France's Sud Aviation were both
   working on designs, called the Type 233 and Super-Caravelle,
   respectively. Both were largely funded by their respective governments.
   The British design was for a trans-Atlantic-ranged aircraft for around
   100 people, while the French were intending to concentrate on a
   medium-range sector.

   The designs were both ready to start prototype construction in the
   early 1960s, but the cost was so great that the British government made
   it a requirement that BAC look for international co-operation.
   Approaches were made to a number of countries, but only France showed
   real interest. The development project was negotiated as an
   international treaty between the two countries rather than a commercial
   agreement between companies and included a clause, originally asked for
   by Britain, issuing penalties for cancellation (Britain's Treasury
   would later twice come close to cancelling the project). A draft treaty
   was signed on 28 November 1962. By this time, both companies had been
   merged into new ones, thus the Concorde project was now a part of the
   British Aircraft Corporation and Aerospatiale.

   The consortium secured orders for over 100 new airliners from the
   premier airlines of the day. Pan Am, BOAC and Air France were the
   launch customers with six Concordes each. Other airlines in the order
   book included: Panair do Brasil, Japan Airlines, Lufthansa, American
   Airlines, United Airlines, Air Canada, Braniff, Iran Air, Qantas, CAAC,
   Middle East Airlines and TWA.

   The aircraft was initially referred to in Britain as "Concorde," with
   the French spelling, but was officially changed to "Concord" by Harold
   Macmillan in response to a perceived slight by Charles de Gaulle. In
   1967, at the French roll-out in Toulouse the British Government
   Minister for 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 recounts a tale of a letter from an irate Scotsman claiming: "you
   talk about 'E' for England, but part of it is made in Scotland." Given
   Scotland's contribution of providing the nose cone for the aircraft,
   Benn replied "it was also 'E' for 'Ecosse'"(the French name for
   Scotland) "—and I might have added 'e' for extravagance and 'e' for
   escalation as well!"

   Construction of two prototypes began in February 1965: Concorde 001,
   built by Aerospatiale at Toulouse, and Concorde 002, by BAC at Filton,
   Bristol. Concorde 001 made her first test flight from Toulouse on 2
   March 1969 and first went supersonic on 1 October. As the flight
   programme progressed, 001 embarked on a sales and demonstration tour on
   4 September 1971. Concorde 002 followed suit 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 the new Dallas/Fort Worth
   International Airport to commemorate the airport's opening.

   These trips led to orders for over 70 aircraft. However, a combination
   of factors led to a sudden number of order cancellations. The 1970s oil
   crisis (Concorde used more fuel per passenger mile than her subsonic
   competitors), acute financial difficulties of the partner airlines, a
   spectacular crash of the competing Soviet Tupolev Tu-144, along with
   environmental concerns such as the sonic boom, take-off noise and
   pollution. Eventually, only Air France and British Airways, (the
   successor to BOAC) took up their orders, with the two governments
   continuing to take a cut of any profits made. In the case of BA, 80% of
   the profit was kept by the government until 1984, while the cost of
   buying the aircraft was covered by a state loan.
   Pre-production Concorde number 101 on display at the Imperial War
   Museum, Duxford, UK
   Enlarge
   Pre-production Concorde number 101 on display at the Imperial War
   Museum, Duxford, UK

   The United States had cancelled its supersonic transport (SST) program
   in 1971. Two designs had been submitted; the Lockheed L-2000, looking
   like a scaled-up Concorde, lost out to the Boeing 2707, which had
   originally been intended to be faster, carry 300 passengers and feature
   a swing-wing design. Industry observers in France and the United
   Kingdom suggested that part of the American opposition to Concorde on
   grounds of noise pollution was, in fact, orchestrated by, or at least
   encouraged by, the United States Government, out of spite at not being
   able to propose a viable competitor, despite President John F.
   Kennedy's impassioned 1963 statement of commitment. Other countries,
   such as Malaysia, also ruled out Concorde supersonic overflights due to
   noise concerns.

   Both European airlines flew demonstration and test flights from 1974
   onwards. The testing of Concorde set records that still have not been
   surpassed; it undertook 5,335 flight hours in the prototype,
   pre-production and first production aircraft alone. A total of 2,000
   test hours were at supersonic speeds. This statistic equates to
   approximately four times as many as similarly sized subsonic commercial
   aircraft. Unit costs were £23 million (US$46 million) in 1977.
   Development cost overrun was 600%.

Technological features

   An unusual camera angle on the final Concorde landing
   Enlarge
   An unusual camera angle on the final Concorde landing
   The flight deck.
   Enlarge
   The flight deck.

   Many features common in early 21st century airliners were first used in
   Concorde.

   For high speed and optimization of flight:
     * Double-delta ( ogee/ ogival) shaped wings
     * Rolls-Royce/ Snecma Olympus turbojet engines with reheat (
       afterburners) and variable inlet ramps
     * Supercruise capability
     * Thrust-by-wire engines, predecessor of today's FADEC-controlled
       engines
     * Droop-nose section for improved visibility in landing

   For weight-saving and enhanced performance:
     * Mach 2.04 for optimum fuel consumption (supersonic drag minimum,
       although turbojet engines are more efficient at high speed)
     * Mainly aluminium construction for low weight and relatively
       conventional manufacture (higher speeds would have ruled out
       aluminium)
     * Full-regime autopilot and autothrottle allowing "hands off" control
       of the aircraft from climb out to landing
     * Fully electrically controlled analogue fly-by-wire flight controls
       systems
     * Multifunction flight control surfaces
     * High-pressure hydraulic system of 28 MPa (4,000 lbf/in²) for
       lighter hydraulic systems components
     * Fully electrically controlled analogue brake-by-wire system
     * Pitch trim by shifting fuel around the fuselage for
       centre-of-gravity control
     * Parts milled from single alloy billet reducing the part-number
       count

   Concorde's primary legacy is in the experience gained in her design and
   manufacture which later became the basis of the Airbus consortium. For
   example, Snecma Moteurs' involvement with the Concorde programme
   prepared the company's entrance into civil engine design and
   manufacturing, opening the way for Snecma to establish CFM
   International with General Electric and produce the successful CFM
   International CFM56 series engines.

   Although Concorde was a technological marvel when introduced into
   service in the 1970s, 30 years later, her cockpit, cluttered with
   analogue dials and switches looked dated. With no competition, there
   was no commercial pressure to upgrade Concorde with enhanced avionics
   or passenger comforts, as occurred in other airliners of the same
   vintage (e.g. Boeing 747).

   The key partners, BAC (later to become BAE Systems) and Aerospatiale
   (later to become EADS), were the joint owners of Concorde's type
   certificate. Responsibility for the Type Certificate transferred to
   Airbus with formation of Airbus SAS.

Main problems overcome during design

   G-AXDN, Duxford, close up of engines.
   Enlarge
   G-AXDN, Duxford, close up of engines.

   Many issues were overcome whilst researching and developing Concorde.

Movement of centre of pressure

   When any aircraft passes the critical mach of that particular airframe,
   the centre of pressure shifts rearwards. This causes a pitch down force
   on the aircraft as the centre of gravity remains where it was. The
   engineers designed the wings in a specific manner to reduce this shift.
   However, there was still a shift of about 2 m. This could have been
   countered by the use of trim controls, but at such high speeds this
   would have caused a dramatic increase in the drag on the aircraft.
   Instead, the distribution of fuel along the aircraft was shifted during
   acceleration and deceleration to move the centre of gravity,
   effectively acting as an auxiliary trim control.

Engines

   To be economically viable, Concorde needed to be able to fly reasonably
   long distances, and this required high efficiency. For optimum
   supersonic flight, the engines needed to have a small frontal
   cross-sectional area to minimise drag and a low bypass ratio to give a
   high, supersonic exhaust speed. Turbojets were thus the best choice of
   engines. The more efficient and quieter high bypass turbofan engines
   such as used on Boeing 747s could not be used. The engine chosen was
   the twin spool Rolls-Royce/Snecma Olympus 593, a version of the Olympus
   originally developed for the Vulcan bomber, but further developed for
   Concorde.
   Concorde's ramp system
   Enlarge
   Concorde's ramp system

   The inlet design for Concorde's engines was especially critical. All
   conventional jet engines can only intake air at around Mach 0.5; the
   air, therefore, needs to be slowed from the Mach 2.0 airspeed that
   enters the engine inlet. In particular, Concorde needed to control the
   shockwaves this reduction in speed generates to avoid damage to the
   engines. This was done by a pair of ramps and an auxiliary flap, whose
   position was moved during flight to slow the air down. The ramps were
   at the top of the engine compartment and moved down and the auxiliary
   flap moved both up and down allowing air to flow in or out. During
   take-off, when the engine's air demand was high, the ramps were flat at
   the top and the auxiliary flap was in, allowing more air to enter the
   engine. As the aircraft approached Mach 0.7, the flap closed; at Mach
   1.3, the ramps came into effect, removing air from the engines which
   was then used in the pressurization of the cabin. At Mach 2.0, the
   ramps had covered half their total possible distance. They also helped
   reduce the work done by the compressors as they not only compressed the
   air but also increased the air temperature.
   Concorde engine twin intake displayed in a museum from Ciudad Juarez,
   Mexico. (Museo del Concorde) Enlarge
   Concorde engine twin intake displayed in a museum from Ciudad Juarez,
   Mexico. ( Museo del Concorde)

   Engine failure causes large problems on conventional subsonic aircraft;
   not only does the aircraft lose thrust on that side but the engine is a
   large source of drag, causing the aircraft to yaw and bank in the
   direction of the engine which has failed. If this could have happened
   to Concorde at supersonic speeds, it would almost certainly have caused
   a catastrophic failure of the airframe. However, during an engine
   failure, an engine's air intake needs are virtually zero, so in
   Concorde the immediate effects of the engine failure were countered by
   the opening of the auxiliary flap and the full extension of the ramps,
   which deflected the air downwards past the engine, gaining lift and
   streamlining the engine, thus minimising the drag effects of the failed
   engine. In tests, Concorde was able to shut down both engines on the
   same side of the aircraft at Mach 2 without any control problems.

   The aircraft used reheat ( afterburners) at take-off and to pass
   through the high- drag transonic regime (i.e. "go supersonic").
   Although the engines were just barely capable of reaching Mach 2
   without reheat, it was discovered operationally that it burnt more fuel
   that way, since the aircraft took much longer to accelerate even though
   reheat is quite inefficient.

Heating issues

   Beside engines, the hottest part of the structure of any supersonic
   aircraft is the nose, and Concorde was no exception. The engineers
   wanted to use ( duralumin) aluminium throughout the aircraft, due to
   its familiarity, cost and ease of construction. The highest temperature
   that aluminium could sustain over the life of the aircraft was a
   maximum of 127 °C, which limited the top speed to Mach 2.02.

   Concorde actually went through two cycles of heating and cooling during
   a flight, first cooling down as it gained altitude, then heating up
   after going supersonic. The reverse happened when descending and
   slowing down. This had to be factored into the metallurgical modelling.
   Owing to the heat generated by compression of the air as Concorde
   traveled supersonically, the fuselage would extend by as much as thirty
   centimetres (almost 1 foot), the most obvious manifestation of this
   being a gap that would open up on the flight deck between the flight
   engineer's console and the bulkhead.

   A way was needed to keep the cabin cool. Concorde used the fuel as a
   place to dump the heat from the air conditioning, as well as to cool
   the hydraulics.

   In spite of this, during supersonic flight, the windows in the cockpit
   became too hot to touch.

Structural issues

   Due to the high speeds at which Concorde travelled, large forces were
   applied to the entire aircraft structure during banks and turns. This
   caused twisting and the distortion of the aircraft's structure. This
   was resolved by the neutralization of the outwards elevons at high
   speeds. Only the innermost elevons which are attached to the strongest
   area of the wings, are active.

   Concorde ended up with quite small passenger windows. Research showed
   that at the extremely high altitude that Concorde flew, a larger
   window, if broken, could have led to the passengers and crew passing
   out before the aircraft could be brought down to a safe altitude.
   Standard oxygen masks would not have helped. The windows were therefore
   made smaller so that the compressors could maintain sufficient cabin
   pressure during the descent.

Brakes

   Due to a relatively high average take-off speed (250 miles per hour),
   Concorde needed good brakes. Concorde's brakes were one of the first
   major uses of anti-lock braking systems which stop the wheels from
   locking when fully applied, allowing greater deceleration and/or
   control during braking, particularly in the wet.

   The brakes were carbon-based and could bring Concorde (going at 190
   mph, weighing up to 185 tons / 188 tonnes) to a stop from an aborted
   take-off within one mile (1600 m). This braking manoeuver brought the
   brakes to temperatures between 300 °C to 500 °C, requiring several
   hours for cooling.

Increased radiation exposure

   The high altitude at which Concorde cruised meant passengers received
   almost twice the flux of extra-terrestrial ionising radiation as those
   travelling on a conventional long-haul flight. Because of the
   proportionally reduced flight time, however, the overall equivalent
   dose was less than a conventional flight over the same distance.
   Unusual solar activity would lead to an increase in incident radiation,
   therefore the flight deck was fitted with a radiometer and an
   instrument to measure the rate of decrease of radiation. If the level
   was too high, Concorde would descend to below 47,000 feet (14 000 m).
   The rate of decrease indicator indicated whether the aircraft needed to
   descend further, decreasing the amount of time the aircraft was at an
   unsafe altitude.

Droop nose

   Concorde's famous drooping nose was a compromise between the need for a
   streamlined design to reduce drag and increase aerodynamic efficiency
   in flight and the need for the pilot to see properly during taxi,
   take-off, and landing operations. A delta wing aircraft takes off and
   lands with a high angle of attack (that is, a high nose angle) compared
   to subsonic aircraft due to the way the delta wing generates lift. The
   pointed nose would obstruct the pilots' view of taxiways and runways,
   so Concorde's nose was designed to allow for different positioning as
   appropriate for different operations. The droop nose was accompanied by
   a moving visor that would be retracted into the nose prior to the nose
   being lowered. When the nose was raised back to horizontal, the visor
   would be raised ahead of the front cockpit windscreen for further
   aerodynamic streamlining in flight.

   Concorde's nose is famous as the "droop nose," but in flight the nose
   was not kept in this position. A controller in the cockpit allowed the
   visor to be retracted and the nose to be lowered to five degrees below
   the standard horizontal position for use in taxi and take-off
   operations. Following take-off and after clearing the airport, the nose
   and visor would be raised. Shortly before landing, the visor would
   again be retracted and the nose would be lowered to 12.5 degrees below
   horizontal for maximum visibility. Upon landing, the nose was quickly
   raised to the five-degree position to avoid the possibility of damage.
   On very rare occasions, the aircraft could take off with the nose fully
   down as well.

   A final possible position had the visor retracted into the nose but the
   nose in the standard horizontal position. This setup was used for
   cleaning the windscreen and for short subsonic flights.

   The prototype Concordes, 001 and 002, had two fixed "glass holes" on
   their retractable visors. The Federal Aviation Administration objected
   to that restrictive visibility and demanded a different design before
   it would permit Concorde to serve US airports, which led to the
   redesigned visor used on the production aircraft as well as on the four
   "pre-production" aircraft (101, 102, 201, and 202).

Scheduled flights

   Concorde G-BOAF. The final ever flight of Concorde landing at Filton
   Airfield, near Bristol, on 26 November 2003
   Enlarge
   Concorde G-BOAF. The final ever flight of Concorde landing at Filton
   Airfield, near Bristol, on 26 November 2003

   Scheduled flights began on 21 January 1976 on the London-Bahrain and
   Paris-Rio routes. The U.S. Congress had just banned Concorde landings
   in the US, mainly due to citizen protest over sonic booms, preventing
   launch on the coveted transatlantic routes.

   When the US ban for over-water supersonic flight was lifted in February
   1977, New York banned Concorde locally. Left with little choice on the
   destination, AF and BA started transatlantic services to Washington,
   D.C. on 24 May. The ban came to an end on 17 October 1977 when the
   Supreme Court of the United States declined to overturn a lower court's
   ruling rejecting the Port Authority's efforts to continue the ban.
   Scheduled service from Paris and London to New York's John F. Kennedy
   Airport began on 22 November 1977. Flights operated by BA were
   generally coded "BA001" through "BA004." (It was noted in the noise
   report that Air Force One, at the time, a Boeing 707, was, in fact,
   louder than Concorde at subsonic speeds and for take-off and landing.)

   While commercial jets take seven hours to fly from New York to Paris,
   the average flight time on the transatlantic routes was just under 3.5
   hours. Up to 2003, Air France and British Airways continued to operate
   the New York services daily. Additionally, Concorde flew to Barbados's
   Grantley Adams International Airport during the winter holiday season
   and, occasionally, to charter destinations such as Rovaniemi, Finland.
   On 1 November 1986, a chartered Concorde circumnavigated the world in
   31 hours and 51 minutes.

   For a brief period in 1977, and again from 1979 to 1981, British
   Airways and Singapore Airlines shared a Concorde for flights between
   Bahrain and Singapore Paya Lebar Airport. The aircraft, G-BOAD, was
   painted in Singapore Airways livery on the port side and British
   Airways livery on the starboard. The service was discontinued after
   three months because of noise complaints from the Malaysian government;
   it could only be reinstated when a new route bypassing Malaysian
   airspace was implemented. However, an ongoing dispute with India
   prevented Concorde from reaching supersonic speeds in Indian airspace,
   so the route was eventually declared not viable. From September 1978 to
   November 1982, during the Mexican oil boom, Air France flew Concorde
   twice weekly to Mexico City's Benito Juárez International Airport via
   Washington, D.C. The worldwide economic crisis during that period,
   resulted in the cancellation of the route to Mexico City; the last
   flights were almost empty. From time to time, Concorde came back to the
   region on chartered flights with stops in Mexico City and Acapulco.

   Between 1984 and 1991, British Airways flew a thrice-weekly Concorde
   service to London from Miami. This was accomplished subsonically by
   extending the Dulles flight to Miami and returning the same way.

   From 1978 to 1980, Braniff International Airways leased 10 Concordes,
   five each from British Airways and Air France. These were used on
   subsonic flights from Dallas-Fort Worth to IAD, feeding the routes of
   BA and AF to London and Paris. The aircraft were registered in both the
   United States and their home countries for legal reasons: a sticker
   would cover up each aircraft's European registration while it was being
   operated by Braniff. On DFW-IAD flights, Concorde had Braniff flight
   crews although they maintained their native airline livery. However,
   the flights were not profitable for Braniff and were usually less than
   50% booked, which forced Braniff to end its tenure as the only U.S.
   Concorde operator in May 1980.

Passenger experience

   Concorde interior.
   Enlarge
   Concorde interior.

   Passenger experience on Concorde differed in many ways from that on
   subsonic commercial airliners. British Airways and Air France
   configured the passenger cabin as a single class with around 100 seats
   — four seats across with a central aisle. Headroom in the central aisle
   was barely six feet (1.8 m) and the leather seats were unusually narrow
   with legroom comparable to economy class on large airliners. With
   almost no room for overhead storage, even carry-on luggage was severely
   restricted.

   In the 1990s, features which were common in the first class and
   business class cabins of a long haul Boeing 747 flight such as video
   entertainment, rotating or reclining seats and perambulatory areas were
   absent from Concorde. However, the flight time from London to New York
   of approximately 3.5 hrs compensated for the lack of those features.
   There was usually a plasma display at the front of the cabin showing
   either the altitude, the air temperature or current speed in Mach
   number.

   To make up for these missing "comfort" features, a high level of
   passenger service was maintained. Meals were served using specially
   designed compact Wedgwood crockery with short silver cutlery.

   The experience of passing through the sound barrier was less dramatic
   than might be expected. The moment, accompanied by a slight surge in
   acceleration, would be announced by one of the pilots.

   At twice the conventional airliner's cruising altitude, the view from
   the windows clearly showed the curvature of the Earth and turbulence
   was rare. During the supersonic cruise, although the outside air
   temperature was typically -60 °C, air friction would heat the external
   skin at the front of the aircraft to approximately +120 °C, making the
   windows warm to the touch and producing a noticeable temperature
   gradient along the length of the cabin, resulting in Concorde expanding
   in length by up to thirty centimetres (twelve inches), during flight.

   Concorde was able to overtake or outrun the sun on routes where
   subsonic airliners fell behind. On westbound flights it was possible to
   arrive at a local time earlier than the local departure time. On
   certain early evening transatlantic flights departing from Heathrow or
   Paris, it was possible to take off at night and catch up with the sun,
   landing in daylight; from the cockpit the sun could be seen rising from
   the horizon in the west. This was much publicised by British Airways,
   who used the slogan, "Arrive before you leave."

Paris crash

   On 25 July 2000, Air France Flight 4590, registration code: F-BTSC,
   crashed in Gonesse, France, killing all 100 passengers and nine crew on
   board the flight, as well as four people on the ground.

   The crash was caused by a titanium strip (part of a thrust reverser)
   that fell from a Continental Airlines DC-10 that had taken off about
   four minutes earlier. This metal fragment punctured Concorde's tyres,
   which then disintegrated. A piece of rubber hit the fuel tank and broke
   an electrical cable. The impact caused a shockwave that fractured the
   fuel tank some distance from the point of impact. This caused a major
   fuel leak from the tank which then ignited. The crew shut down engine
   number 2 in response to a fire warning but were unable to retact the
   landing gear, hampering the aircraft's climb. With engine number 1
   surging and producing little power, the aircraft was unable to gain
   height or speed, entering a rapid pitch-up then a violent descent,
   rolling left. The impact occured with the stricken aircraft tail low
   and crashing into the Hotelissimo Hotel in Gonesse.

   Concorde had, until the accident, been the safest working passenger
   airliner in the world in terms of passenger deaths per kilometre
   travelled, but statistically, after the accident it was the worst.
   While an aircraft's safety cannot be accurately measured from a single
   accident, the crash of the Air France Concorde nonetheless proved to be
   the beginning of the end for the type.

   The accident subsequently led to a programme of modifications to
   Concorde, including more secure electrical controls, Kevlar lining to
   the fuel tanks and specially-developed, burst-resistant tyres.

Return to service

   The first test-flight after the modifications departed from London
   Heathrow on 17 July 2001, piloted by BA Chief Concorde Pilot Mike
   Bannister. During the three hour and twenty minute flight over the
   mid-Atlantic towards Iceland, Bannister attained Mach 2 and 60,000 ft
   before returning to RAF Brize Norton. The test flight, intended to
   resemble the London-New York route, was declared a success and was
   watched on live TV, as well as by crowds on the ground at both
   locations.

   The first BA passenger flight took place on 11 September 2001, and was
   in the air during the attacks on the World Trade Centre. This was not a
   revenue flight, as all the passengers were BA employees.

   Normal commercial operations resumed on 7 November 2001 by BA and AF
   (aircraft G-BOAE and F-BTSD), with service to New York JFK where
   passengers were welcomed by the mayor, Rudy Giuliani.

Withdrawal from service

   On 10 April 2003, British Airways and Air France simultaneously
   announced that they would retire Concorde later that year. They cited
   low passenger numbers following the 25 July 2000 crash, the slump in
   air travel following 9/11 and rising maintenance costs.

   That same day, Sir Richard Branson offered to buy British Airways'
   Concordes at their "original price of £1" for service with his Virgin
   Atlantic Airways. Branson claimed this to be the same token price that
   British Airways had paid the British Government, but BA denied this and
   refused the offer. However, although the cost of buying the aircraft
   was £26 million each, the money for buying the aircraft was loaned by
   the government - this loan was written off when British Airways was
   privatised in 1987.

   After posting large losses on their Concorde flights in the early
   1980s, British Airways paid a flat sum of £16.5 million in 1984 to the
   UK government to buy their Concordes outright. After doing a market
   survey, and discovering that their target customers thought that
   Concorde was more expensive than it actually was, BA progressively
   raised prices to match these perceptions. It is reported that BA then
   ran Concorde at a profit, unlike their French counterparts. Although BA
   refused to open the accounts, it has been reported to be up to £50
   million per year in the most profitable year and a total revenue of
   £1.75 billion on costs of £1 billion.

   Branson later wrote to The Economist ( 23 October 2003) that his final
   offer was "over £5 million" and that he had intended to operate the
   fleet "for many years to come." Any hope of Concorde remaining in
   service was further thwarted by Airbus' unwillingness to provide
   maintenance support for the ageing airframes.

   It has been suggested that Concorde was not cancelled for the reasons
   usually given, and that the airlines discovered during the grounding
   that Concorde's first class passengers were loyal to the airlines and
   carrying them on subsonic aircraft gave greater revenue and that this
   was the real reason for the withdrawal from service.

   The small hope remaining for Concorde today rests with a dedicated
   group of French volunteer engineers keeping one of the youngest
   Concordes in near airworthy condition. This group of engineers, working
   on the Air France aircraft retired to the Le Bourget Air and Space
   Museum in Paris, hope that one day Concorde will be able to show her
   majesty by taking to the skies. Concordes based in Britain, however,
   have had their fluids drained and systems have been disconnected,
   making it even harder for her to regain airworthiness certification. It
   appears that the French hopes present a much better chance of seeing
   her fly in the future.

Air France

   Air France made its final commercial Concorde landing in the United
   States in New York City from Paris on 30 May 2003. Firetrucks sprayed
   the traditional arcs of water above the aircraft on the tarmac of John
   F. Kennedy airport. Concorde F-BTSD operated the airline's final
   scheduled supersonic service, returning to Paris on a misty May
   morning. The final passenger flight for the airline's SSTs was marked
   by a charter around the Bay of Biscay. During the following week, on 2
   June and 3 June 2003, F-BTSD flew a final round-trip from Paris to New
   York and back for airline staff and long-time employees in the
   airline's Concorde operations. Air France's final Concorde flight took
   place on 27 June 2003 when F-BVFC retired to Toulouse.

   An auction of Concorde parts and memorabilia for Air France was held at
   Christie's in Paris, on 15 November 2003. Thirteen hundred people
   attended with several lots exceeding their predicted values by an order
   of magnitude.

   Two French Concordes at Le Bourget and Toulouse have been run
   occasionally, and it is possible that they could be prepared for future
   flights for special occasions.

British Airways

   Parade flight at Queen's Golden Jubilee
   Enlarge
   Parade flight at Queen's Golden Jubilee

   BA's last Concorde departure from the Grantley Adams International
   Airport in Barbados was on 30 August 2003. BA conducted a mini North
   American farewell tour in October 2003. G-BOAG visited Toronto Pearson
   International Airport on 1 October 2003, G-BOAD visited Boston's Logan
   International Airport on 8 October 2003, and G-BOAG visited Washington
   Dulles International Airport on 14 October 2003. G-BOAD's flight to
   Boston set a record for the fastest transatlantic flight from east to
   west, making the trip from London Heathrow in three hours, five
   minutes, thirty-four seconds.

   In a final week of farewell flights around the United Kingdom, a
   Concorde visited Birmingham on 20 October, Belfast on 21 October,
   Manchester on 22 October, Cardiff on 23 October, and Edinburgh on 24
   October. Each day the aircraft made a return flight out and back into
   Heathrow to the cities concerned, often overflying those cities at low
   altitude. Over 650 competition winners and 350 special guests were
   carried.

   On 22 October, Heathrow ATC contrived for the inbound flight BA9021C, a
   special from Edinburgh and BA002 from New York to land simultaneously
   on the left and right runways respectively.

   On the evening of 23 October 2003, the Queen consented to the
   illumination of Windsor Castle, as Concorde's last ever west-bound
   commercial flight departed London, and flew overhead. This is an honour
   normally reserved for major state events and visiting dignitaries.

   British Airways retired its aircraft the next day, 24 October. G-BOAG
   left New York to a fanfare similar to her Air France predecessor's,
   while two more made round-trips, G-BOAF over the Bay of Biscay,
   carrying VIP guests including many former Concorde pilots, and G-BOAE
   to Edinburgh. The three aircraft then circled over London, having
   received special permission to fly at low altitude, before landing in
   sequence at Heathrow. The two round-trip Concordes landed at 4:01 and
   4:03 p.m. BST, followed at 4:05 by the one from New York. All three
   aircraft then spent 45 minutes taxiing around the airport before
   finally disembarking the last supersonic fare-paying passengers. The
   pilot of the New York to London flight was Mike Bannister. All of BA's
   Concordes have been grounded, have lost their airworthiness
   certificates and have been drained of hydraulic fluid. Ex-chief
   Concorde pilot and manager of the fleet Jock Lowe, estimated it would
   cost £10-15 million to make G-BOAF (at Filton) airworthy again. BA
   maintains ownership of the Concordes, and has stated that their
   Concordes will not be flown again.

   On 1 December 2003, Bonhams held an auction of British Airways'
   Concorde artifacts at Kensington Olympia, in London. Items sold
   included: a Machmeter, nose cone, Concorde pilot and passenger seats
   and even cutlery, ashtrays and blankets used onboard. Proceeds of about
   £¾ million resulted,with the first half-million going to Get Kids
   Going!, a charity which gives disabled children and young people the
   opportunity to participate in sport.

Aircraft histories

   20 Concordes were built, six for development and 14 for commercial
   service.
   Concorde G-BOAG at Museum of Flight, Seattle, Washington, USA
   Enlarge
   Concorde G-BOAG at Museum of Flight, Seattle, Washington, USA

   These were:
     * Two prototypes
     * Two pre-production aircraft
     * 16 production aircraft
          + The first two of these did not enter commercial service
          + Of the 14 which flew commercially, 12 were still in service in
            April 2003

   All but two of these aircraft - a remarkably high percentage for any
   commercial fleet, are preserved; the two which are not preserved are
   F-BVFD (cn 211), withdrawn from service in the 1980s and scrapped in
   1994, and F-BTSC (cn 203), which crashed in Paris.

   CAPTION: Concorde Aircraft

   Number Reg First Flew Last Flew Hours Location
   001 F-WTSS 2 March 1969 19 October 1973 812 The Museum of Air and
   Space, Le Bourget, France
   002 G-BSST 9 April 1969 4 March 1976 836 Fleet Air Arm Museum,
   Yeovilton, UK
   101 G-AXDN 17 December 1971 20 August 1977 632 Imperial War Museum,
   Duxford, UK
   102 F-WTSA 10 January 1973 20 May 1976 656 Musee Delta, Orly Airport,
   Paris, France
   201 F-WTSB 6 December 1973 19 April 1985 909 Airbus Factory, Toulouse,
   France
   202 G-BBDG 13 December 1974 24 December 1981 1282 Brooklands Museum,
   Weybridge, Surrey, UK
   203 F-BTSC 31 January 1975 25 July 2000 11989 Destroyed in air crash
   outside Paris, France
   204 G-BOAC 27 February 1975 31 October 2003 22260 Manchester Airport
   Viewing Park, UK
   205 F-BVFA 27 October 1976 12 June 2003 17824 Steven F. Udvar-Hazy
   Centre, Chantilly, Virginia USA
   206 G-BOAA 5 November 1975 12 August 2000 22768 Museum of Flight, East
   Lothian, Scotland
   207 F-BVFB 6 March 1976 24 June 2003 14771 Sinsheim Auto & Technik
   Museum, Germany
   208 G-BOAB 18 May 1976 15 August 2000 22296 Heathrow Airport, London,
   UK
   209 F-BVFC 9 July 1976 27 June 2003 14332 Airbus Factory, Toulouse,
   France
   210 G-BOAD 25 August 1976 10 November 2003 23397 Intrepid Sea-Air-Space
   Museum, New York, USA; temporary move to Floyd Bennett Field in
   Brooklyn pending for duration of restoration and rehabilitation work on
   Intrepid, as of late 2006
   211 F-BVFD 10 February 1977 27 May 1982 5814 Broken up
   212 G-BOAE 17 March 1977 17 November 2003 23376 Grantley Adams
   International Airport, Barbados
   213 F-BTSD 26 June 1978 14 June 2003 12974 The Museum of Air and Space,
   Le Bourget, France
   214 G-BOAG 21 April 1978 5 November 2003 16239 Museum of Flight,
   Seattle, USA
   215 F-BVFF 26 December 1978 11 June 2000 12421 Charles de Gaulle
   Airport, Paris, France
   216 G-BOAF 20 April 1979 26 November 2003 18257 Filton Aerodrome,
   Bristol, UK

Cultural and political impact

   Concorde remains a powerful symbol, both for her technology and her
   sculptural shape. It is a symbol of great national pride to many in
   Britain and France; in France it was thought of as a French aircraft,
   in Britain as British.

Environmental impacts

   The reaction of people to the prospect of severe overflying noise also
   represented a socially important change. Prior to Concorde's flight
   trials the developments made by the civil aviation industry were
   largely accepted by developed democratic governments and their
   electors. The popular backlash (particularly on the eastern seaboard of
   the USA) against the noise of Concorde represented a political turning
   point and thereafter scientists and technologists in many industries
   began to take environmental and societal impacts more seriously,
   accepting that engineers, powerful investors and governments could not
   always allow their economic or career interests to prevail.

   One of the key protesters to the "SST" (Super Sonic Transport - the US
   term given to the Concorde aircraft), Carol Vendi, ultimately gained
   political ground over the whole issue and was elected to the US
   Congress. Concorde led directly to a general noise reduction in
   aircraft flying out of JFK; it was found that Concorde was actually
   quieter than some aircraft (partly due to the pilots temporarily
   throttling back their engines to reduce noise during overflight of
   residential areas). This caused the other airlines to have to follow
   suit.

   Concorde produced nitrogen oxides in its exhaust, damaging to the ozone
   layer at the airliner's stratospheric cruising altitudes. However, the
   effects are more complex, since nitrogen oxides react with ozone,
   destroying chlorine and removing it. Chlorine is the main ozone
   destroying pollutant. It has been pointed out that other, lower-flying,
   airliners actually produce ozone during their flights in the
   troposphere, but vertical transit of gases between the two is highly
   restricted. There have been accusations that the anti-SST lobby
   overstated the case for ozone degradation to suit their political ends.

   From this perspective, Concorde's technical leap forward can be viewed
   as boosting the public's (and the media's) understanding of conflicts
   between technology and the environment. In France, the use of acoustic
   fencing alongside TGV tracks might not have been achieved without the
   1970s furore over aircraft noise. In Britain, the CPRE have issued
   tranquillity maps since 1990 and public agencies are starting to do
   likewise.

Public perception

   Concorde was normally perceived as a privilege of the rich, but special
   circular (non-landing) or one-way (with return by coach or ship)
   charter flights were arranged to bring a trip within the means of
   moderately well-off enthusiasts.

   Her enigma was such that an overflight would frequently temporarily
   halt day-to-day business, and she was usually referred to by the
   British as simply "Concorde" and the French as "le Concorde" (rather
   than "un Concorde"), as if there were only one. (In fact, this article
   follows the British usage.)

   As a symbol of national pride, a plane from the BA fleet made
   occasional flypasts at selected Royal events, major airshows and other
   special occasions, sometimes in formation with the Red Arrows. On the
   final day of commercial service, public interest was so great that
   grandstands were erected at London's Heathrow Airport to afford a view
   of the final arrivals. Crowds filled the boundary road around the
   airport and there was extensive media coverage.

   Thirty-seven years after her first test flight, Concorde was announced
   the winner of the Great British Design Quest, organised by the BBC and
   the Design Museum. A total of 212,000 votes were cast with Concorde
   beating design icons such as the Mini, mini skirt, Jaguar E-type, Tube
   map and the Supermarine Spitfire.

Artistic

   Public reaction to the Air France Concorde crash was cited by Jeremy
   Clarkson during a 2004 TV appearance on Parkinson as a primary
   inspiration for his book I Know You Got Soul.

   Concorde's global prominence led it to feature as the star in the
   poorly received and outlandish film sequel The Concorde: Airport '79.

Trivia

     * In transatlantic flight, Concorde travelled more than twice as fast
       as other aircraft, and other aircraft frequently appeared to be
       flying backwards.
     * Concorde had restrictions on its livery; the majority of the
       surface had to be white to avoid overheating the aluminium
       structure due to the supersonic heating effects of Mach 2. In 1996,
       however, Air France briefly painted F-BTSD in a predominantly blue
       livery (with the exception of its wings) as part of a promotional
       deal with Pepsi Cola. In this paint scheme, Air France were advised
       to remain at Mach 2 for no more than twenty minutes at a time, but
       there was no restriction at speeds under Mach 1.7. F-BTSD was
       chosen for the promotion because she was not then scheduled to
       operate any long flights that would require extended Mach 2
       operations.
     * On all the Concordes that had a supersonic flight before
       retirement, the flight engineers placed their hats in the gap that
       appears at high speed between the console and the bulkhead before
       it cooled, where the hats remain to this day. However, in the case
       of the Seattle museum's Concorde, a protruding cap was cut off by a
       thief in an apparent attempt to steal it, leaving a part behind. An
       amnesty led to the severed cap being returned; the museum has been
       examining options to reattach it in some way.
     * Due to turbojet engines being highly inefficient at low speeds,
       Concorde burned two tonnes of fuel taxiing to the runway. After
       landing, only the two outer engines were run to conserve fuel
       because the full 152,200 lb of thrust (677 kN) was not required. A
       Concorde once ran out of fuel taxiing back to the terminal after a
       flight; the pilot was fired.
     * The delta-shaped wings allowed Concorde to attain a higher angle of
       attack than conventional aircraft, as it allowed the formation of
       large low pressure vortices over the entire upper wing surface,
       maintaining lift. It is this low pressure which caused Concorde to
       disappear into a bank of fog on humid days. These only formed at
       low air speeds, meaning that during the initial climb out and
       throughout the approach, Concorde would experience light turbulence
       and buffeting.
     * Throughout the entire approach, Concorde was on the "back side" of
       the drag curve.
     * Braniff International pilots flew both AF and BA Concordes (10 in
       total).
     * During the multi-venue Live Aid, when famine relief concerts were
       held on 13 July 1985, pop star Phil Collins flew a Concorde from
       London so that he could perform at both venues (London and
       Philadelphia) on the same day.
     * Concorde travelled, per passenger, 17 miles for each gallon of fuel
       (mpg) (an efficiency of 20 litres per hundred kilometres
       (l/100km)). This is comparable to a Gulfstream G550 business jet
       (~16 mpg or 18 l/100km per passenger), but much larger than, say a
       Boeing 747-400 (~91 mpg or 3.1 l/100km per passenger)
     * Concorde's cruising speed exceeded the top speed of the terminator.
       It was possible to take off from London just after sunset and see
       the sun rise in the west on the way to America.
     * Concorde flew fast enough that the weight of everyone onboard was
       temporarily reduced by about 1% when flying east. This was due to
       centrifugal effects since the airspeed added to the rotation speed
       of the Earth. Flying west, the weight increased by a smaller amount
       (about 0.3%), because it cancelled out the normal rotation, and,
       with it, the normal centrifugal force and replaced it with a
       smaller rotation in the opposite direction.
     * Concorde also flew high enough that the weight of everyone onboard
       was reduced by an additional 0.6% due to the increased distance
       from the centre of the Earth.
     * The speed of sound varies greatly with the air temperature, meaning
       that if Concorde entered a warm pocket of air, her speed could
       increase from Mach 2.0 to more than Mach 2.04, without her actual
       velocity changing. The speed of sound is around 332 m/s at standard
       temperature and pressure.

Specifications

General characteristics

     * Crew: 9
     * Capacity: 100 passengers
     * Length: 202 ft 4 in (61.66 m)
     * Wingspan: 84 ft 0 in (25.6 m)
     * Height: 40 ft 0 in (12.2 m)
     * Fuselage internal length: 129 ft 0 in (39.32 m)
     * Fuselage max external width: 9 ft 5 in (2.88 m)
     * Fuselage max internal width: 8 ft 7 in (2.63 m)
     * Fuselage max external height: 10 ft 10 in (3.32 m)
     * Fuselage max internal height: 6 ft 5 in (1.96 m)
     * Wing area: 3,856 ft² (358.25 m² )
     * Lift/drag ratio: Low speed- 3.94, Approach- 4.35, 250 knots, 10,000
       ft- 9.27, Mach 0.94- 11.47, Mach 2.04- 7.14))
     * Empty weight: 173,500 lb (78,700 kg)
     * Useful load: 245,000 lb (111,130 kg)
     * Powerplant: 4× Rolls-Royce/ SNECMA Olympus 593 Mk 610 afterburning
       turbojets
          + Dry thrust: 32,000 lbf dry (140 kN)
          + Thrust with afterburner: 38,050 lbf (169 kN) each

Performance

     * Maximum speed: Mach 2.04 (1,350 mph, 2,170 km/h)
     * Range: 3,900 nm (4,500 mi, 7,250 km)
     * Service ceiling: 60,000 ft (18,300 m)
     * Rate of climb: 1,525 m (5,000 ft)/min (25,41 m/s)
     * Wing loading: lb/ft² (kg/m²)
     * Thrust/weight: .373
     * Fuel consumption: 46.85 lb/mi (13.2 kg/km)
     * Maximum nose tip temperature: 260 °F (127 °C)

Comparison with other supersonic aircraft

   The only other supersonic airliner that was in direct competition with
   Concorde was the Russian TU-144, that ultimately was a failure.
   Although the TU-144 entered service earlier, it was retired in 1978.
   The still-born project, the Boeing 2707 was America's entry into the
   supersonic sweepstakes.

   The early version of the TU-144D had significantly lower range than
   Concorde, largely due to its underpowered engines. It required reheat
   to maintain Mach 2.0, and cruised at just Mach 1.6 without. The vehicle
   had poor control at low speeds, due to simpler, dedicated supersonic
   wing design. In addition, the Tupolev cabin noise was far higher and
   the vehicle cruder and much less refined, due to more rapid
   development, and whereas Concorde had sophisticated antilock brakes,
   the Tu-144 required parachutes to land. It also had two crashes, one at
   the Paris airshow, which made further sales impossible, and made things
   very difficult for Concorde as well, the other crash on a cargo flight.
   The later versions of the Tupolev had retractable canards for better
   low speed control and military engines from Tu-160 that gave them
   nearly the range of Concorde. It had 126 seats, and top speed of Mach
   2.35 (made possible due to titanium and steel leading edges). Whilst
   theoretically a more competitive plane this version was not exportable
   due to the military engines.

   The American design was to have been larger, seating 300. It was also
   intended to reach higher speeds of up to Mach 3.0, which made the
   construction much more difficult, as high temperatures ruled out the
   use of duralumin. Running a few years behind Concorde, the extra costs
   of these features may have helped to kill the project. The discovery
   that sonic booms were quite capable of reaching the ground also meant
   that the aircraft was subject to the same environmental concerns that
   contributed to hindering commercial success of Concorde. The American
   government had spent over $1 billion on the project and finished
   empty-handed.

Possible replacements

   In November 2003, European aviation company EADS, (the company behind
   Airbus), announced that it was considering working with Japanese
   companies to develop a larger, faster replacement for Concorde.
   However, recent news reports suggest only $1m is being invested every
   year into research, much less than the $1bn needed for the development
   of a viable supersonic airliner.

   In October 2005, JAXA, the Japan Aerospace eXploration Agency,
   undertook aerodynamic testing of a scale model of a airliner designed
   to carry 300 passengers at Mach 2. If pursued to commercial deployment,
   it would be expected to be in service around 2020 - 2025.

   Research into supersonic business jets is ongoing.

   The British company, Reaction Engines Limited, with 50% EU money, are
   researching LAPCAT, a design for a hydrogen fuelled plane carrying 300
   passengers, capable of flying nonstop from Brussels to Sydney at Mach
   5+ in 4.6 hours.

Films and television

   Concorde has been featured or mentioned in:
     * The Wild Geese (1978): Colonel Faulkner ( Richard Burton) arrives
       at London Heathrow on Concorde.
     * The Concorde: Airport '79: The Concorde used for the live-action
       aerial filming was the same Air France Concorde that crashed 21
       years later on 25 July 2000.
     * The Concorde Affair (Concorde Affaire in orig.) Italy 1979.
       Director: Ruggero Deodato
     * Moonraker(1979): James Bond arrives in Rio de Janeiro on an Air
       France Concorde. Air France flew Concorde on the Paris- Dakar- Rio
       route at the time.
     * The Long Good Friday(1980): Harold Shand ( Bob Hoskins) flies into
       Heathrow on Concorde.
     * Superman II (1980): Superman overtakes Concorde on his way to
       Paris.
     * Doctor Who: Featured in the 1982 story " Time-Flight."
     * The Transformers (1984-1987): As the Aerialbot leader Silverbolt in
       the animated TV series.
     * The Bonfire of the Vanities (film)(1990): Maria Ruskin ( Melanie
       Griffith) arrives in New York on an Air France Concorde. The film's
       Second Unit Director, Eric Schwab, went to considerable effort to
       calculate the exact time and day when a runway at JFK would line up
       exactly with the setting sun, to serve as a spectacular backdrop
       for the landing Concorde.
     * Absolutely Fabulous (1992-2004): Edina Monsoon and Patsy Stone made
       regular trips to New York aboard Concorde.
     * Coming to America (1988): Prince Akeem and Semmi arrive in New York
       on a British Airways Concorde.
     * Snatch (2000): The character Cousin Avi flew on Concorde from New
       York City to London to see Doug the Head, then back, after an
       unexpected turn of events and again to London in the closing scene
       of the film.
     * Sabrina (1995): Linus Larrabe Harrison Ford takes an Air France
       Concorde from New York to Paris in order to meet Sabrina on time
       since she had left New York earlier on a conventional Air France
       flight.
     * Only Fools and Horses: In the 1996 Christmas episode, the family is
       seen aboard Concorde on their way home from America after attending
       the auction of the John Harrison pocket watch which made them
       millionaires.
     * The Parent Trap (1998 version): Hallie and her father take Concorde
       so that they can beat the twins' mother and Annie to London.
     * Cats & Dogs (2001) Concorde was used to transport secret agent dogs
       from the UK to the USA.
     * National Treasure (2004): Concorde is shown on the New York
       Harbour.
     * SuperSonic Dream (2005): A PBS NOVA documentary about Concorde

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