20 Years Ago Today; Air France Flight 4590 crashes after takeoff from de Gaulle Airport

[Dennis Donovan]

https://en.wikipedia.org/wiki/Air_France_Flight_4590



Air France Flight 4590 was an international charter flight, from Charles de Gaulle Airport, Paris to John F. Kennedy International Airport, New York, flown by an Aérospatiale-BAC Concorde. On the afternoon of Tuesday, 25 July 2000 at 14:44:31 (UTC, 16:44:31 time local in France) , the aircraft serving the flight (registration F-BTSC) ran over debris on the runway during takeoff, blowing a tyre, and sending debris flying into the underside of the left wing, and into the landing gear bay.

The fuel tank that was inside the left wing was unusually full, and the resulting lack of air space in the tank caused it to rupture and send fuel pouring outward with great force when debris from the tire struck the wing thus creating a shock wave that weakened the tank. Debris, which flew into the landing gear bay, severed power wiring for the landing gear, making it impossible to retract the gear as the aircraft climbed. Sparks produced by the broken wiring ignited fuel from the ruptured fuel tank and along with the fire came a reduction of thrust from Engine 1 and 2. Lack of thrust, the high drag caused by the inability to retract the gear, along with fire damage to the flight controls, made it impossible to control the aircraft with the result that it crashed into a hotel in nearby Gonesse two minutes after takeoff, killing all 109 people on board and four more people in the hotel, with another person in the hotel critically injured.

The flight was chartered by German company Peter Deilmann Cruises, and 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. It was the only fatal Concorde accident during its 27-year operational history.

Aircraft and crew


The aircraft involved was a 25-year-old Aérospatiale-BAC Concorde (registration F-BTSC, serial number 203) that had its maiden flight on 31 January 1975 (during testing the aircraft's registration was F-WTSC). The aircraft was purchased by Air France on 6 January 1976. It was powered by four Rolls-Royce Olympus 593/610 turbojet engines, each of which were equipped with afterburners. The aircraft's last scheduled repair took place on 21 July 2000, four days before the accident; no problems were reported during the repair. At the time of the crash, the aircraft had flown for 11,989 hours and had made 4,873 take-off and landing cycles.

The cockpit crew consisted of the following:

Captain Christian Marty, 54 years old, who had been with Air France since 1967. He had 13,477 flight hours, including 317 hours on the Concorde. Marty had also flown the Boeing 727, 737, Airbus A300, A320, and A340 aircraft.

First officer Jean Marcot, 50, who had been with Air France since 1971 and had 10,035 flight hours, with 2,698 of them on the Concorde. He had also flown the Aérospatiale N 262, Morane-Saulnier MS.760 Paris, Sud Aviation Caravelle and Airbus A300 aircraft.

Flight engineer Gilles Jardinaud, 58, who had been with Air France since 1968. He had 12,532 flight hours, of which 937 of them were on the Concorde aircraft. Jardinaud had also flown the Sud Aviation Caravelle, Dassault Falcon 20, Boeing 727, 737, and 747 (including the -400 variant) aircraft.

Crash
The wind at the airport was light and variable that day, and was reported to the cockpit crew as an eight-knot (15 km/h; 9 mph) tailwind as they lined up on runway 26R.

Five minutes before the Concorde departed, a Continental Airlines McDonnell Douglas DC-10-30 took off from the same runway for Newark International Airport and lost a titanium alloy strip that was part of the engine cowl, identified as a wear strip 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. The Concorde ran over this piece of debris during its take-off run, cutting the right front tyre (tyre No 2) and sending a large chunk of tyre debris (4.5 kilograms or 9.9 pounds) into the underside of the left wing at an estimated speed of 140 metres per second (310 mph). It did not directly puncture any of the fuel tanks, but it sent out a pressure shockwave that ruptured the number 5 fuel tank at the weakest point, just above the undercarriage. Leaking fuel gushing out from the bottom of the wing was most likely ignited either by an electric arc in the landing gear bay (debris cutting the landing gear wire) or through contact with hot parts of the engine. Engines 1 and 2 both surged and lost all power, then engine 1 slowly recovered over the next few seconds. A large plume of flame developed, and the flight engineer shut down engine 2 in response to a fire warning and the captain's command.

Air traffic controller Gilles Logelin noticed the flames before the Concorde was airborne and informed the flight crew. However, the aircraft had passed V1 speed, at which point takeoff is considered unsafe to abort. The plane did not gain enough airspeed with the three remaining engines as damage to the landing gear bay door prevented the retraction of the undercarriage. The aircraft was unable to climb or accelerate, and its speed decayed during the course of its brief flight. The fire caused damage to the inner elevon of left wing and it began to disintegrate, melted by the extremely high temperatures. Engine number 1 surged again, but this time failed to recover, and the right wing lifted from the asymmetrical thrust, 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 they lost control due to falling speed and the aircraft stalled, crashing into the Hôtelissimo Les Relais Bleus Hotel. A video of the burning plane on takeoff and the aftermath of the crash was captured by a passing driver.

The crew was trying to divert to nearby Paris–Le Bourget Airport, but accident investigators stated that a safe landing would have been highly unlikely, given the aircraft's flightpath. The cockpit voice recorder (CVR) recorded the last intelligible words in the cockpit (translated into English):

Co-pilot: "Le Bourget, Le Bourget, Le Bourget."
Pilot: "Too late (unclear)."
Control tower: "Fire service leader, correction, the Concorde is returning to runway zero nine in the opposite direction."
Pilot: "No time, no (unclear)."
Co-pilot: "Negative, we're trying Le Bourget" (four switching sounds).
Co-pilot: "No (unclear)."
Fire service leader: "De Gaulle tower from fire service leader, can you give me the situation of the Concorde?" (two gongs and sound of switch, followed by another switch and sounds likened to objects being moved)
Pilot: (unclear, sounds like exertion)
Pilot: (unclear, sounds like exertion)
Pilot: (unclear, sounds like exertion)
End of recording

Fatalities
All the passengers and crew, and four employees of the Hotelissimo hotel, were killed in the crash. Most of the passengers were German tourists en route to New York for a cruise.



Aftermath
Until the crash, Concorde had been considered among the world's safest aeroplanes. The crash contributed to the end of the aircraft's career.

A few days after the crash, all Concordes were grounded, pending an investigation into the cause of the crash and possible remedies.

Air France's Concorde operation had been a money-losing venture, and it is claimed that the aeroplane had been kept in service as a matter of national pride; British Airways claimed to make a profit on its Concorde operations. According to Jock Lowe, a Concorde pilot, until the crash of Air France Flight 4590 at Paris, the British Airways Concorde operation made a net average profit of about £30M (equivalent to £51M today) a year. Commercial service was resumed in November 2001 after a £17M (£28M today) safety improvement service, until the type was retired in 2003.

Investigation
The official investigation was conducted by France's accident investigation bureau, the Bureau d'Enquêtes et d'Analyses pour la Sécurité de l'Aviation Civile (BEA).

Post-accident investigation revealed that the aircraft was over the maximum takeoff weight for ambient temperature and other conditions, and 810 kg (1,790 lb) over the maximum structural weight, loaded so that the centre of gravity was aft of the take-off limit. Fuel transfer during taxiing left the number 5 wing tank 94 percent full. A 30-centimetre (12 in) spacer normally keeps the left main landing gear in alignment, but it had not been replaced after recent maintenance; the BEA concluded that this did not contribute to the accident.

The final report was issued on 16 January 2002.

Conclusions
The BEA concluded that:

The aircraft was overloaded by 810 kilograms (1,790 lb) above the maximum safe takeoff weight. Any effect on takeoff performance from this excess weight was negligible.

After reaching takeoff speed, the tyre of the number 2 wheel was cut by a metal strip (a wear strip) lying on the runway, which had fallen from the thrust reverser cowl door of the number 3 engine of a Continental Airlines DC-10 that had taken off from the same runway five minutes previously. This wear strip had been replaced at Tel Aviv, Israel, during a C check on 11 June 2000, and then again at Houston, Texas, on 9 July 2000. The strip installed in Houston had been neither manufactured nor installed in accordance with the procedures as defined by the manufacturer.

The aircraft was airworthy and the crew were qualified. The landing gear that later failed to retract had not shown serious problems in the past. Despite the crew being trained and certified, no plan existed for the simultaneous failure of two engines on the runway, as it was considered highly unlikely.

Aborting the takeoff would have led to a high-speed runway excursion and collapse of the landing gear, which also would have caused the aircraft to crash.

While two of the engines had problems and one of them was shut down, the damage to the plane's structure was so severe that the crash would have been inevitable, even with the engines operating normally.

Alternative theories
Two factors that the BEA found to be of negligible consequence to the crash, an unbalanced weight distribution in the fuel tanks and loose landing gear, were re-evaluated by British investigators and former French Concorde pilots. They accused Air France of negligence because they concluded these factors caused the aircraft to veer off course on the runway reducing its takeoff speed to below the critical minimum.

Air France had discovered that its maintenance staff had not replaced or renewed a spacer in one of the four tyres in the rear left landing gear (it was found in a workshop after the crash). This skewed the alignment of the landing gear because a strut was able to wobble in any direction with 3° of movement. The problem was exacerbated on the left gear's three remaining tyres by the uneven fuel load. Drag marks left on the runway by the left rear landing wheels show the Concorde was veering to the left as it accelerated towards takeoff.

Due to the veer, the Concorde travelled further down the runway than normal because it was failing to gain sufficient takeoff speed. It was after it had passed its usual takeoff point on the runway that it struck the metal strip from the DC-10.

At one point it drifted towards an Air France Boeing 747 which was carrying then-French President Jacques Chirac (who was returning from the 26th G8 summit meeting in Okinawa, Japan).

<snip>


A monument in honour of the crash victims was established at the crash site at Gonesse


N13067, the DC-10 involved, was scrapped at Mojave, California, in 2002

[mahatmakanejeeves]

1. Oh, I hate this. I mean, not the thread, but the way it ended for Concorde.

I never flew in one. My father did once. That was one lucky upgrade.

[DFW]

2. I flew on the Concorde several times

Mostly work-related, although Air France offered me and my family a special deal to attend my grandfather's 100th birthday in New York, and it included the return to Düsseldorf via Paris on the Concorde. That was the only time I took the Air France Concorde. All the other times were on British Airways, usually to Washington, but once to New York. The service on BA was better.

It was not a comfortable plane to fly. The seats were four to a row, and squeezed together like a DC-9. The view from the window was spectacular, and the three hour flight time was very cool, but unless you got a special deal (as I did every time I flew it), it was unbelievably expensive, and the fuel consumption made me cringe.

Most of the Germans on that flight worked for a company near us that had chartered the flight, and my wife had slightly known several of the passengers.

[dewsgirl]

3. K and R😔