Concorde supersonic aircraft

Because of tank heating, fuel volatiUty is also more critical in supersonic aircraft. For example, the Concorde tank is pressurized to prevent vapor losses which could be significant at high altitude where fuel vapor pressure may equal atmospheric pressure. The tank can reach 6.9 kPa (1 psi) at the end of a flight. The need to deoxygenate fuel for thermal stabiUty in the HSCT will doubdess require a similar pressurized system. 

Concorde Supersonic Aircraft in the Lower Stratosphere, Science, 270, 70-74 (1995a). 

Because of its high strength and infusibility even at very high temperatures, as well as its low density, carbon-fiber-reinforced carbon is most suitable as disc brake material for supersonic aircraft such as the civilian CONCORDE and nearly all military jets see Figure 2. For this application, 2D carbon/carbon composites are preferred. The performance... 

At that time there were plans to build enormous fleets of supersonic aircraft 500 Boeing SSTs, Concordes, and in the Soviet Union the Tupolevs, nicknamed as Concordskys. 

Primary applications of carbon-carbon composite materials are in the aerospace industry, where in spite of their high cost, they can still be very cost effective. The use of carbon-carbon composites for the brakes of the Concorde supersonic aircraft is reported to have produced a weight saving of over 10001b, which translates into significant economies in operation. 

A related issue associated with an eventual fleet of supersonic aircraft is the particulate Emission Index. If the El of small particles measured by Fahey et al. (1995) in the exhaust of the Concorde is characteristic of the proposed HSCT fleet, significant increases in particle number and surface area would be likely to occur in the lower stratosphere, with concomitant effects on stratospheric chemistry. 

Fahey, D. W., et al. (1995) Emission measurements of the Concorde supersonic aircraft in the lower stratosphere. Science, 270,10-1 A. 

The first commercial supersonic transport, the Concorde, operates on Jet A1 kerosene but produces unacceptable noise and exhaust emissions. Moreover, it is limited in capacity to 100 passengers and to about 3000 miles in range. At supersonic speed of Mach 2, the surfaces of the aircraft are heated by ram air. These surfaces can raise the temperature of fuel held in the tanks to 80 °C. Since fuel is the coolant for airframe and engine subsystems, fuel to the engine can reach 150°C (26). An HSCT operated at Mach 3 would place much greater thermal stress on fuel. To minimize the formation of thermal oxidation deposits, it is likely that fuel deflvered to the HSCT would have to be deoxygenated. 

The next generation of high speed civil transports (HSCTs) is designed to carry 250-300 passengers at supersonic speeds [5]. The European version of this aircraft (a second generation Concorde) has a proposed speed of Mach 2.05, consistent with transatlantic operation, whereas the US plane has a proposed speed of Mach 2.4 for transpacific operation. Estimated surface skin temperatures will increase from 110°C to 177°C simply as a result of the speed difference. The operational life at these elevated temperatures... 

C/C composite brake discs are used in some military aircrafts like F-15, F-16, YF-16 and also in the commercial supersonic airplane, the Concorde. Some European racing cars are also equipped with carbon brakes. 

The research of Paul Crutzen, the third recipient of the Nobel Prize for Chemistry in 1995, involved the effect of nitric oxide (NO) on the destruction of stratospheric ozone. Unlike CFCs, which may take 50 to 100 years to diffuse into the upper atmosphere, nitric oxide is introduced directly to the stratosphere in the exhaust of high-altitude aircraft. Early in the 1970s, the United States considered construction of a large fleet of supersonic transport airplanes (SSTs), similar to the Concorde. Environmentalists argued, based in part on the work of Paul Crutzen, that to do so would significantly endanger the ozone layer. 

Further additions of iron, nickel, manganese and vanadium increase the mechanical properties at temperatures between 100 and 300 °C. These are alloys 2618A and 2219, which in the T6 temper provide good stability and creep resistance up to 100-150 °C. Alloy 2618 A is used in aircraft construction (including supersonic Concorde aircraft)... 

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