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Air France Flight 4590 Concorde Disaster Paris

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• published: 24 Aug 2016
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Was this crash really caused by the tire rubber or perhaps something more sinister? Air France Flight 4590 was an Aérospatiale-BAC Concorde, registration F-BTSC, on a scheduled international flight from Paris, France, to New York City, on 25 July 2000, local time 16:43 CET. While taking off, the aircraft ran over debris on the runway, blowing a tyre and puncturing a fuel tank, leading to fire and engine failure. All 100 passengers and nine crew members aboard the Concorde died when it crashed into a hotel in nearby Gonesse, while on the ground four people were killed and one was critically injured. The flight was chartered by German company Peter Deilmann Cruises; the passengers were on their way to board the cruise ship MS Deutschland in New York City for a 16-day cruise to Manta, Ecuador. This was the only fatal Concorde accident during its 27-year operational history. Post-accident investigation revealed that the aircraft was at or over the maximum takeoff weight for ambient temperature and other conditions, and 810 kilograms (1,790 lb) over the maximum structural weight. As it left the gate, it was loaded such that the centre of gravity was aft of the take-off limit. Fuel transfer during taxiing left the number five wing tank 94% full. A 12-inch spacer that normally keeps the left main landing gear in alignment had not been replaced after recent maintenance; however, the French Bureau for Accident Investigation concluded that this did not contribute to the accident. The wind at the airport was light and variable that day, and was reported to the cockpit crew as an eight knot tailwind as they lined up on runway 26R. Five minutes before the Concorde departed, a Continental Airlines DC-10 heading for Newark, New Jersey took off from the same runway and had lost a titanium alloy strip (part of the engine cowl, identified as a wear strip) that was about 435 millimetres (17.1 in) long, 29 to 34 millimetres (1.1 to 1.3 in) wide and 1.4 millimetres (0.055 in) thick. A runway inspection, scheduled for an hour and a half before the Continental airplane took off, had not been carried out. During the Concorde's takeoff run, it ran over this piece of debris, cutting a tyre and sending a large chunk of tyre debris (4.5 kilograms or 9.9 pounds) into the underside of the aircraft's wing at an estimated speed of 140 metres per second (310 mph). Although it did not directly puncture any of the fuel tanks, it sent out a pressure shockwave that ruptured the number five fuel tank at the weakest point, just above the undercarriage. Leaking fuel gushing out from the bottom of the wing was most likely ignited by an electric arc in the landing gear bay or through contact with hot parts of the engine. At the point of ignition, engines one and two both surged and lost all power, but engine one slowly recovered over the next few seconds. A large plume of flame developed; the flight engineer then shut down engine two, in response to a fire warning and the captain's command. Air traffic controller Gilles Logelin noticed the flames before the Concorde was airborne, however with only 2 km (1.2 mi) of runway remaining and travelling at a speed of 328 km/h (204 mph), its only option was to take off. The Concorde would have needed at least 3 km (1.9 mi) of runway to abort safely. Having passed V1 speed, the crew continued the takeoff, but the plane did not gain enough airspeed with the three remaining engines, because damage to the landing gear bay door prevented the retraction of the undercarriage.The aircraft was unable to climb or accelerate, maintaining a speed of 200 knots (370 km/h; 230 mph) at an altitude of 60 metres (200 ft). The fire caused damage to the port wing, which began to disintegrate—melted by the extremely high temperatures. Engine number one surged again, but this time failed to recover. Due to the asymmetric thrust, the starboard wing lifted, banking the aircraft to over 100 degrees. The crew reduced the power on engines three and four in an attempt to level the aircraft, but with falling airspeed they lost control and the aircraft stalled, crashing into the Hôtelissimo Les Relais Bleus Hotel near the airport. The crew was trying to divert to nearby Le Bourget Airport, but accident investigators stated that a safe landing, given the aircraft's flight path, would have been highly unlikely.