CONCORDE
The Aerospatiale/BAC Concorde is a British French turbojet powered supersonic passenger airliner that was operated until 2003. It had a maximum speed over twice the speed of sound, at Mach 2.04 (1,354 mph or 2,180 km/h at cruise altitude), with seating for 92 to 128 passengers. First flown in 1969, Concorde entered service in 1976 and continued flying for the next 27 years. It is one of only two supersonic transports to have been operated commercially; the other is the Soviet-built Tupolev Tu-144, which operated in the late 1970.
The original programme cost estimate was £70 million. The programme experienced huge overruns and delays, with the program eventually costing £1.3 billion. It was this extreme cost that became the main factor in the production run being much smaller than anticipated. Later, another factor, which affected the viability of all supersonic transport programmes, was that supersonic flight could be used only on ocean crossing routes, to prevent sonic boom disturbance over populated areas. With only seven airframes each being operated by the British and French, the per-unit cost was impossible to recoup, so the French and British governments absorbed the development costs. British Airways and Air France were able to operate Concorde at a profit, in spite of very high maintenance costs, because the aircraft was able to sustain a high ticket price.
Among other destinations, Concorde flew regular transatlantic flights from London's Heathrow Airport and Paris's Charles de Gaulle Airport to John F. Kennedy International Airport in New York, Washington Dulles International Airport in Virginia and Grantley Adams International Airport in Barbados; it flew these routes in less than half the time of other airliners.
Concorde won the 2006 Great British Design Quest, organised by the BBC and the Design Museum of London, beating other well known designs such as the BMC Mini, the miniskirt, the Jaguar E-Type, the London Tube map and the Supermarine Spitfire. The type was retired in 2003, three years after the crash of Air France Flight 4590, in which all passengers and crew were killed. The general downturn in the commercial aviation industry after the September 11 attacks in 2001 and the end of maintenance support for Concorde by Airbus (the successor company of Aerospatiale) also contributed to the retirement.
General Features
Concorde is an ogival delta winged aircraft with four Olympus engines based on those employed in the RAF's Avro Vulcan strategic bomber. It is one of the few commercial aircraft to employ a tailless design (the Tupolev Tu-144 being another). Concorde was the first airliner to have a (in this case, analogue) fly-by-wire flight-control system; 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:
Double delta (ogee/ogival) shaped wings
Variable engine air intake ramp system controlled by digital computers
Supercruise capability
Thrust-by-wire engines, predecessor of today's FADEC-controlled engines
Droop nose for better landing visibility
For weight-saving and enhanced performance:
Mach 2.02 (~2,154 km/h or 1,338 mph) cruising speed for optimum fuel consumption (supersonic drag minimum and turbojet engines are more efficient at higher speed) Fuel consumption at Mach 2 (2,120 km/h; 1,320 mph) and at altitude of 60,000 feet (18,000 m) was 4,800 US gallons per hour (18,000 L/h).
Mainly aluminium construction using a high temperature alloy similar to that developed for aero-engine pistons. This material gave low weight and allowed 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
High pressure hydraulic system using 28 MPa (4,100 psi) for lighter hydraulic components, tripled independent systems ("Blue", "Green", and "Yellow") for redundancy, with an emergency ram air turbine (RAT) stored in the port-inner elevon jack fairing supplying "Green" and "Yellow" as backup.
Complex air data computer (ADC) for the automated monitoring and transmission of aerodynamic measurements (total pressure, static pressure, angle of attack, side-slip).
Fully electrically controlled analogue brake-by-wire system
Pitch trim by shifting fuel fore-and-aft for centre-of-gravity (CoG) control at the approach to Mach 1 and above with no drag penalty. Pitch trimming by fuel transfer had been used since 1958 on the B-58 supersonic bomber.
Parts made using "sculpture milling", reducing the part count while saving weight and adding strength.
No auxiliary power unit, as Concorde would only visit large airports where ground air start carts are available.
ACCİDENTS AND İNCİDENTS
Air France Flight 4590
On 25 July 2000, Air France Flight 4590, registration F-BTSC, crashed in Gonesse, France, after departing from Charles de Gaulle Airport en route to John F. Kennedy International Airport in New York City, killing all 100 passengers and nine crew members on board as well as four people on the ground. It was the only fatal accident involving Concorde.
According to the official investigation conducted by the Bureau d'Enquetes et d'Analyses pour la Sécurité de l'Aviation Civile (BEA), the crash was caused by a metallic strip that had fallen from a Continental Airlines DC-10 that had taken off minutes earlier. This fragment punctured a tyre on Concorde's left main wheel bogie during take off. The tyre exploded, and a piece of rubber hit the fuel tank, which caused a fuel leak and led to a fire. The crew shut down engine number 2 in response to a fire warning, and with engine number 1 surging and producing little power, the aircraft was unable to gain altitude or speed. The aircraft entered a rapid pitch up then a sudden descent, rolling left and crashing tail-low into the Hôtelissimo Les Relais Bleus Hotel in Gonesse.
The claim that a metallic strip caused the crash was disputed during the trial both by witnesses (including the pilot of then French President Jacques Chirac's aircraft that had just landed on an adjacent runway when Flight 4590 caught fire) and by an independent French TV investigation that found a wheel spacer had not been installed in the left-side main gear and that the plane caught fire some 1,000 feet from where the metallic strip lay. British investigators and former French Concorde pilots looked at several other possibilities that the BEA report ignored, including an unbalanced weight distribution in the fuel tanks and loose landing gear. They came to the conclusion that the Concorde veered off course on the runway, which reduced takeoff speed below the crucial minimum. John Hutchinson, who had served as a Concorde captain for 15 years with British Airways, said "the fire on its own should have been 'eminently survivable; the pilot should have been able to fly his way out of trouble'", had it not been for a "lethal combination of operational error and 'negligence' by the maintenance department of Air France" that "nobody wants to talk about".
On 6 December 2010, Continental Airlines and John Taylor, a mechanic who installed the metal strip, were found guilty of involuntary manslaughter; however, on 30 November 2012, a French court overturned the conviction, saying mistakes by Continental and Taylor did not make them criminally responsible.
Before the accident, Concorde had been arguably the safest operational passenger airliner in the world with zero passenger deaths per kilometres travelled; but there had been two prior non fatal accidents and a rate of tyre damage some 30 times higher than subsonic airliners from 1995 to 2000.
Safety improvements were made in the wake of the crash, including more secure electrical controls, Kevlar lining on the fuel tanks and specially developed burst-resistant tyres. The first flight with the modifications departed from London Heathrow on 17 July 2001, piloted by BA Chief Concorde Pilot Mike Bannister. During the 3 hour 20 minute flight over the mid Atlantic towards Iceland, Bannister attained Mach 2.02 and 60,000 ft (18,000 m) 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, and by crowds on the ground at both locations.
The first flight with passengers after the accident took place on 11 September 2001, landing shortly before the World Trade Center attacks in the US. This was not a commercial flight: 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 Mayor Rudy Giuliani greeted the passengers.
Other Accidents And İncidents
Concorde had suffered two previous non-fatal accidents that were similar to each other.
12 April 1989: A Concorde of British registration, G-BOAF, on a chartered flight from Christchurch, New Zealand, to Sydney, suffered a structural failure in flight at supersonic speed. As the aircraft was climbing and accelerating through Mach 1.7 a "thud" was heard. The crew did not notice any handling problems, and they assumed the thud they heard was a minor engine surge. No further difficulty was encountered until descent through 40,000 feet at Mach 1.3, when a vibration was felt throughout the aircraft, lasting two to three minutes. Most of the upper rudder had become separated from the aircraft at this point. Aircraft handling was unaffected, and the aircraft made a safe landing at Sydney. The UK's Air Accidents Investigation Branch (AAIB) concluded that the skin of the rudder had been separating from the rudder structure over a period of time before the accident due to moisture seepage past the rivets in the rudder. Furthermore, production staff had not followed proper procedures during an earlier modification of the rudder, but the procedures were difficult to adhere to. The aircraft was repaired and returned to service.
21 March 1992: A Concorde of British registration, G-BOAB, on a scheduled flight from London to New York, also suffered a structural failure in-flight at supersonic speed. While cruising at Mach 2, at approximately 53,000 feet above mean sea level, the crew heard a "thump". No difficulties in handling were noticed, and no instruments gave any irregular indications. This crew also suspected there had been a minor engine surge. One hour later, during descent and while decelerating below Mach 1.4, a sudden "severe" vibration began throughout the aircraft. The vibration worsened when power was added to the No 2 engine, and it was attenuated when that engine's power was reduced. The crew shut down the No 2 engine and made a successful landing in New York, noting only that increased rudder control was needed to keep the aircraft on its intended approach course. Again, the skin had become separated from the structure of the rudder, which led to most of the upper rudder becoming separated in-flight. The AAIB concluded that repair materials had leaked into the structure of the rudder during a recent repair, weakening the bond between the skin and the structure of the rudder, leading to it breaking up in-flight. The large size of the repair had made it difficult to keep repair materials out of the structure, and prior to this accident, the severity of the effect of these repair materials on the structure and skin of the rudder was not appreciated.
The 2010 trial involving Continental Airlines over the crash of Flight 4590 established that from 1976 until Flight 4590 there had been 57 tyre failures involving Concordes during takeoffs, including a near-crash at Dulles Airport on 14 June 1979 involving Air France Flight 54 where a tyre blowout pierced the plane's fuel tank and damaged the port side engine and electrical cables, with the loss of two of the craft's hydraulic systems.
RETİREMENT
On 10 April 2003, Air France and British Airways simultaneously announced they would retire Concorde later that year. They cited low passenger numbers following the 25 July 2000 crash, the slump in air travel following the September 11 attacks, and rising maintenance costs: Airbus (the company that acquired Aerospatiale in 2000) had made a decision in 2003 to no longer supply replacement parts for the aircraft. Although Concorde was technologically advanced when introduced in the 1970s, 30 years later, its analogue cockpit was outdated. There had been little commercial pressure to upgrade Concorde due to a lack of competing aircraft, unlike other airliners of the same era such as the Boeing 747. By its retirement, it was the last aircraft in the British Airways fleet that had a flight engineer; other aircraft, such as the modernised 747-400, had eliminated the role.
On 11 April 2003, Virgin Atlantic founder Sir Richard Branson announced that the company was interested in purchasing British Airways' Concorde fleet "for the same price that they were given them for one pound". British Airways dismissed the idea, prompting Virgin to increase their offer to £1 million each. Branson claimed that when BA was privatised, a clause in the agreement required them to allow another British airline to operate Concorde if BA ceased to do so, but the Government denied the existence of such a clause. In October 2003, Branson wrote in The Economist that his final offer was "over £5 million" and that he had intended to operate the fleet "for many years to come". The chances for keeping Concorde in service were stifled by Airbus's lack of support for continued maintenance.
It has been suggested that Concorde was not withdrawn for the reasons usually given but that it became apparent during the grounding of Concorde that the airlines could make more profit carrying first-class passengers subsonically. A lack of commitment to Concorde from Director of Engineering Alan MacDonald was cited as having undermined BA's resolve to continue operating Concorde.
Other reasons why the attempted revival of Concorde never happened relate to the fact that the narrow fuselage did not allow for "luxury" features of subsonic air travel such as moving space, reclining seats and overall comfort. In the words of The Guardian's Dave Hall, "Concorde was an outdated notion of prestige that left sheer speed the only luxury of supersonic travel."
Air France
Air France Concorde at Paris-Charles de Gaulle Airport
Air France Concorde in Auto & Technik Museum Sinsheim
Air France made its final commercial Concorde landing in the United States in New York City from Paris on 30 May 2003. 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; 1,300 people attended, and several lots exceeded their predicted values. French Concorde F-BVFC was retired to Toulouse and kept functional for a short time after the end of service, in case taxi runs were required in support of the French judicial enquiry into the 2000 crash. The aircraft is now fully retired and no longer functional.
French Concorde F-BTSD has been retired to the "Musée de l'Air" at Paris Le Bourget Airport near Paris; unlike the other museum Concordes, a few of the systems are being kept functional. For instance, the famous "droop nose" can still be lowered and raised. This led to rumours that they could be prepared for future flights for special occasions.
Air France Concorde on display at Steven F. Udvar Hazy Center
French Concorde F-BVFB is at the Auto & Technik Museum Sinsheim at Sinsheim, Germany, after its last flight from Paris to Baden-Baden, followed by a spectacular transport to Sinsheim via barge and road. The museum also has a Tupolev Tu-144 on display this is the only place where both supersonic airliners can be seen together.
In 1989, Air France signed a letter of agreement to donate a Concorde to the National Air and Space Museum in Washington D.C. upon the aircraft's retirement. On 12 June 2003, Air France honoured that agreement, donating Concorde F-BVFA (serial 205) to the Museum upon the completion of its last flight. This aircraft was the first Air France Concorde to open service to Rio de Janeiro, Washington, D.C., and New York and had flown 17,824 hours. It is on display at the Smithsonian's Steven F. Udvar Hazy Center at Dulles Airport.
British Airways
BA Concorde G-BOAB at London Heathrow Airport. This aircraft flew for 22,296 hours between its first flight in 1976 and its final flight in 2000, and has remained there ever since.
British Airways conducted a North American farewell tour in October 2003. G-BOAG visited Toronto Pearson International Airport on 1 October, after which it flew to New York's John F. Kennedy International Airport. G-BOAD visited Boston's Logan International Airport on 8 October, and G-BOAG visited Washington Dulles International Airport on 14 October.
In a week of farewell flights around the United Kingdom, 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, often overflying them at low altitude. On 22 October, both Concorde flight BA9021C, a special from Manchester, and BA002 from New York landed simultaneously on both of Heathrow's runways. On 23 October 2003, the Queen consented to the illumination of Windsor Castle, an honour reserved for state events and visiting dignitaries, as Concorde's last west-bound commercial flight departed London.
British Airways retired its Concorde fleet on 24 October 2003. G-BOAG left New York to a fanfare similar to that given for Air France's F-BTSD, while two more made round trips, G-BOAF over the Bay of Biscay, carrying VIP guests including 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 captain of the New York to London flight was Mike Bannister. The final flight of a Concorde in the US occurred on 5 November 2003 when G-BOAG flew from New York's JFK Airport to Seattle's Boeing Field to join the Museum of Flight's permanent collection. The plane was piloted by Mike Bannister and Les Broadie, who claimed a flight time of three hours, 55 minutes and 12 seconds, a record between the two cities.The museum had been pursuing a Concorde for their collection since 1984. The final flight of a Concorde worldwide took place on 26 November 2003 with a landing at Filton, Bristol, UK.
All of BA's Concorde fleet have been grounded, drained of hydraulic fluid and their airworthiness certificates withdrawn. Jock Lowe, ex-chief Concorde pilot and manager of the fleet estimated in 2004 that it would cost £10–15 million to make G-BOAF airworthy again. BA maintain ownership and have stated that they will not fly again due to a lack of support from Airbus. On 1 December 2003, Bonhams held an auction of British Airways Concorde artefacts, including a nose cone, at Kensington Olympia in London. Proceeds of around £750,000 were raised, with the majority going to charity. G-BOAD is currently on display at the Intrepid Sea, Air & Space Museum in New York. In 2007, BA announced that the advertising spot at Heathrow where a 40% scale model of Concorde was located would not be retained; the model is now on display at the Brooklands Museum, in Surrey, England.
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