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Concorde - The End

The Concorde represented a technological triumph for its British and French developers. However, in the eyes of its potential customers -- the airlines -- the Concorde did not represent a suitable prototype for development into a family of advanced SSTs. Consequently, the Concorde was not allowed the evolutionary cycles that were so important in the development of subsonic transport technology.

Air France Concorde F-BVFD was the first Concorde to be retired following a reduction in routes flown by the French airline. She last flew in May 1982 and was withdrawn from service. She was scrapped in 1994.

Air France Concorde F-BTSC crashed in mid-2000, leading Britain and France to withdraw the remaining planes from service until investigations into the cause of the crash were complete. The accident killed all 109 people on board and four [or five] on the ground. All the passengers on board were Germans, on a special flight chartered by a German Tour operator. The plane burst into flames shortly after take-off from Paris' Charles de Gaulle airport on 25 July 2000. A major fire broke out under the left wing. Problems appeared shortly afterwards on engine N 2 and for a brief period on engine N 1 but the aircraft took off. The aircraft was neither able to climb nor accelerate. The crew shut down engine 2, following an engine fire alarm. The crew found that the landing gear would not retract. The aircraft flew for around a minute but was unable to gain height or speed beyond 200 knots and 200 feet. Engine 1 lost thrust, the aircraft's angle of attack and bank increased sharply. The thrust on engines 3 and 4 fell suddenly and the aircraft crashed onto a hotel at La Patte d'Oie in Gonesse.

The Concorde has been considered among the world's safest planes. The crash was the first of the supersonic jet built by Britain and France. It came a day after British Airways confirmed that hairline cracks had been discovered in the wings of all seven of its Concorde fleet. Immediate attention focussed on previous reports about cracks having been found in the wings of the Concorde fleet. On Monday 24th July -- the day before the crash -- British Airways staff had confirmed that hairline cracks had been discovered in the wing of all seven of its Concorde fleet. Both British Airways and Air France found the microscopic cracks within the previous two months, but no aircraft was grounded until a week earlier when the crack lengthened. Both airlines insisted that the cracks did not cause any safety fears, but one aircraft was grounded after a crack was found to have lengthened. The microscopic' cracks revealed by affected 68ft spars running through both wings towards the rear of the jet. They were not the first problem of the type to affect the airliner - in 1988 cracks were found in bolt holes in a roof panel. The following year an Air France Concorde flying from Paris to New York was forced to turn back after cracks appeared in a porthole. And in 1994 a report revealed the outer widow panes cracked at twice the speed of sound.

Over the following days, a number of diverse causal hypotheses were presented to the public. These ranged from age-related issues, including the possibility of metal fatigue, through to fan-blade separation within the engine or problems involving the maintenance of a thrust reverser immediately prior to take off. While Concorde has two engines on each side, they are far closer together than on other planes. This meant that if something catastrophic happened to one engine it could impact on the other. The Times contained speculation about the impact that staffing changes may have had on Concorde's maintenance before the crash while BBC Online stressed the relatively short time that was available to replace a thrust reverser that was found to be faulty immediately prior to take-off.

The Concorde flight had been delayed for repairs to a thrust reverser, sparking early speculation that faulty work could have contributed to the disaster. Alan Smith, a former Concorde test pilot, said the most likely cause of the accident was a "catastrophic failure" of one of the plane's four engines. "It is possible that a turbine spun out from one engine and impacted upon the one next to it," he said.". (The Times, 26th July, p.1). There are further examples in the same edition, "John Guntripp, a former air crash investigator, said: "Even with two engines lost, the remaining two engines should have had more than sufficient power capable of taking the engine into a climb so what occurred was a very serious disruption of the aircraft's flying control." BA's chief Concorde pilot, Mike Bannister said."These cracks, which the manufacturers have told us are non-safety related cause me no concern. I have been aware of them for a little while and I have complete faith in BA's engineering and in the prudent steps they are taking to address a very small increase in the length of one of the cracks."

BA was keen to stress the aircraft's exemplary safety record and the fact that Concorde clocked up a fraction of the flying hours amassed by subsonic planes. There had also been other dramatic problems in addition to the cracks. In 1991 the rudder of a BA Concorde disintegrated at 56,000ft as the plane flew to New York. In 1998, a BA Concorde was forced to turn back to Heathrow after a 4ft by 2ft panel fell off a wing. And the same year an investigation was launched after part of a BA Concorde rudder fell off during flight. The only major scare came in 1979, when a bad landings blew out plane's tires. The incidents led to design modifications.

The tire problems resurfaced some three days later when investigators confirmed that debris had been found on the runway. By the 28th of July investigators switched their focus to the burst tire theory. French investigators looking into the crash said it was probable that a 16-inch piece of metal found on the runway caused a tire to blow out, sending debris from the tire through fuel tanks and triggering a fire that brought down the plane. During takeoff from runway 26 right at Roissy Charles de Gaulle Airport, shortly before rotation, the front right tire of the left landing gear ran over a strip of metal that had fallen from another aircraft. The tire was damaged and pieces of the tire were thrown against the aircraft structure. The fuel tank didn't puncture, but the shockwave from the impacting tire fragment caused a rupture between the rib at the front of the landing gear well and the skin attached at a 90 angle beneath it (the full fuel tank could not absorb the shock). It was there that fuel spilled out past the landing gear leg, alongside the hot Olympus engine and ignited upon contact with the afterburners.

British aviation authorities formally ruled the Concorde supersonic airliner unfit to fly unless its manufacturers took steps to prevent the problems that led to the fatal Air France Concorde crash. The certificate of navigability was attributed on this basis, and Concorde was back in service by 7 November 2001. Nine of the seven British and five French aircraft remaining in service were modified with new landing gear, fuel tank protection, and structural improvements ordered by aviation authorities. The four modified Air France aircraf and five modified British Airways Concorde returned to service, the remaining aircraft - without these changes and therefore a Certificate of Airworthiness - were withdrawn from service.

BAe/SNIAS Concorde Type 1 airplanes that had been modified in accordance with Airbus Concorde service bulletins No.'s SST 57-078, SST 57-079, SST 57-080, and SST 57-082, had undergone mandatory modification to install Viton and Kevlar liner materials to the fuel tanks. This mandatory modification action resulted from the July 2000 crash. After the airplanes re-entered service, a Kevlar fiber was found in one of the engine fuel systems during fuel filter inspection. This fiber came from one of the modified fuel tanks, and was positioned partially through the fuel filter mesh. The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom (UK), and Rolls-Royce advised that additional kevlar fibers could wash away from tank liners into all four engine fuel systems on the airplane. That condition, if not corrected, could cause contamination of any or all of the four airplane engine fuel control units, causing power loss or one or more engines to shutdown.

In 2003, British Airways and Air France discontinued all Concorde flights because the flights were no longer profitable. On April 14, 2003 British Airways and Air France announced that they would discontinue the supersonic Concorde's commercial service in October 2003. This decision has been made for commercial reasons. The global downturn in demand for premium travel combined with a rise in maintenance costs for the aircraft had brought forward the date of Concorde's retirement. The decision was based on long-term trends rather than recent events and comes at a time when British Airways was having to make difficult choices across the airline. The last Air France flight was on May 31, 2003 and the last British Airways flight was on October 24, 2003. The end of supersonic travel by Concorde may mean that for some it takes longer to cross the Atlantic.

While many felt that the Concorde program proved economically disastrous, several benefits were obtained from it. First, the Concorde showed that an aircraft could be developed and produced which is capable of safe, sustained revenue operations at supersonic speeds. Much has been learned about commercial supersonic aircraft operations which would be extremely beneficial to any future generation of supersonic transports. Secondly, the British and French gained much experience in working together, especially in learning how to manage an advanced technology program with many coordination problems. The Concorde has aided the French in a military regard, specifically in the technology applied to the Mirage series of fighters (Mirage 2000) which is capable of speeds of Mach 2.5. Last, the project helped preserve and focus the French and British commercial aerospace industry, which has gone on to become a major contender in the world commercial air transport market.

There are no commercial supersonic aircraft flying today. The first generation of SSTs was followed by a second generation of supersonic commercial transport projects in the time period between 1986 until about 1999, designs which did not proceed towards the production hardware stage.



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