Design for Excellence failed Air France Flight 4590
Air France Flight 4590 was a chartered flight carrying 100 German passengers to New York. With an impeccable safety record, Christian Marty, one of Air France’s most talented pilots was the captain of this flight. However, there was a one hour delay with the boarding process and investigations found out that it was slightly overweight, beyond the stipulated maximum structural weight of 408,009 pounds for flight.
Rather than burning extra fuel, to compensate for the added weight, Marty decided to pump fuel toward the rear of the plane to shift the centre of gravity allowing the plane to take off appropriately. Alongside this, before takeoff, he was advised that he had unfavourable tailwinds at eight knots whereas it is known that for an aircraft to the off, headwinds are more likely favoured as it provides an added lift. However, he decided to continue as planned to avoid further delays. As he prepared the engines for maximum throttle, he was unaware that a Continental Airlines DC-10 had recently taken off from the same runway. This take-off left titanium wear-strip debris on the runway which went unnoticed since the usual inspection was cancelled due to a routine fire drill that day. This was the major human error that created a sequence of events that resulted in this infamous incident on 25 July 2000.
This flight was modelled on the BAC-Aerospatiale Concorde which had an infamous history of tire problems because of extreme loads and speeds during takeoffs and landings. When Flight 4590 sped down the runway for take-off, the tires encountered the titanium wear-strip debris that had fallen from the DC−10. Titanium, a durable metal sliced into the left tire like a razor. The tire burst, scattering large chunks of rubber which flew out at over 300 mph, hitting the under-side of the flight’s unique delta wing, slicing through the exposed hydraulic lines and electrical wires. The largest of the tire fragments was around four feet long and weighed over ten pounds. This piece hit the weakest spot of fuel tank number 5, which was full. Immediately after the tank was hit, it caused a hydrodynamic pressure surge resulting in an explosive outburst of the fuel, as it began to ooze out through a one square feet large aluminium panel in the underbelly of the aircraft. With the sparks from the ruptured wirings acting as a catalyst, a violent fire broke out. The fire sensors located in the cockpit were blaring and almost instinctively the flight engineer shut down both the left engines. Unfortunately, the flight at already reached speeds from where there was no turning back. The flight was running out of runway and he had to take off. Desperate attempts were continually made to pull up nose trying to make an emergency landing at a nearby airport. However, these efforts proved futile as the plane struggled with the additional drag from the landing gear which the pilots could not retract due to leakages in the hydraulic systems. With its undercarriage set ablaze, Air France Flight 4590 never elevated above 200 feet. The delta wings could not be kept airborne at such low speed and it crashed under two minutes from takeoff, approximately 5 kilometres from the CDG airport. Everyone on board was killed along with the four people on the ground working at the hotel in which they crash-landed on.
Design Elements of Air France Flight 4590
Design for Innovation
This main feature of this landmark aircraft was its innovative design. It used a Rolls Royce/ SNECMA Olympus 593 engine which was the world’s first two-spool axial-flow turbojet engine that provided its high thrust. Along with its tailless design and the delta wing running throughout the body n both sides, it could maintain a steady balance while flying over the speed of
sound. It had a movable nose that provided added balance especially during take-off and landings making the aircraft more aerodynamic, reducing the drag considerably.
Design for Cost
The basic design of the Concorde was far from being cost-efficient. It is argued that the entire project cost the French and British taxpayers over $1.5 billion even before its commercial deployment. However, Air France and other franchises that used this make were set to gain millions with over 160 flights flying across continents every week. The ticket prices were exorbitant and the luxury not so, although, it is still dubbed as an elite mode of transport. There was little space for in-flight travel and a cramped up cockpit. There was a limit set for the weight of luggage lower than the usual standards. In this regard, few stalwarts have stated that this aircraft resembled a pipe that flew at supersonic speed with a few chairs being sceptically added later. The cost of maintenance for such aircraft was over twice the maintenance cost of standard aircraft during this era. And, not at all times were the parts available for replacement.
Design for Reliability
The design for Air France Flight 4590 can be considered sustainable and reliable only concerning the super-fast, supersonic speed it could reach while cruising. The delta wing tailless design was unique and maintained a steady balance even at its maximum speed and provided a stable landing system. However, this aircraft burnt more fuel than conventional aircraft and had less capacity. Which meant it was not as environment friendly as the conventional models. The loud sonic boom it encountered while travelling beyond the speed of sound created noise pollution to an extent that it shattered glassware above the land it flew over. The tire systems were historically faulty as it could not bear the load of the aircraft during taking off and landing.
Conclusion
Most engineering-related disasters involving machinery with complex systems, rarely occur due to just one major reason. Usually, there are a series of interplaying factors involved leading to a cumulative catastrophe. This was the case on July 25, 2000, with the Air France Flight 4590 as well. The project cost British and French taxpayers over $1.5 billion even before the operations began, which a few scholars still consider a drastic underestimate of the actual costs. However, the impending capital costs were written off by government subsidies and a falsely elevated sense of national pride. Beyond the costs incurred, this had other challenges as well. Extreme noise and environmental consequences were topics of concern for anti-Concorde activists. Several nations banned it from their airspace because of the loud ‘sonic boom’ it produced during flight.
