Chartman - lucky man! Never thought I'd ever disagree with you publicly, but have to take exception to your "Vortex under the wing" thesis.
Aircraft fly because the shape of the wing induces low pressure above and slightly higher pressure below. The reduction in pressure above the wing is far greater than the increase in pressure below, to the extent that about 70% of the lift comes from the upper surface. An aircraft is there fore "sucked" into the air more than lifted. Most aircraft achieve this pressure differential by making the air above the wing travel faster than the air below, reducing pressure over the top surface.
The second way of reducing pressure above the wing is to induce a vortex above it, because there is low pressure at the centre of a vortex. Inducing a vortex below the wing would therefore just suck the aircraft into the ground. All wings have vortices that normally start at the wingtips. For most aircraft this is bad news because it is pure drag. The longer and narrower the wing, the smaller the vortex, and this is why glider wings are so long and slender - to minimise this vortex drag. But if you can get the vortex to travel along the wing towards the fuselage, it goes over the top surface of the wing, lowering the pressure. The more swept back the wing, the more the vortex is inclined to travel along it, and this is why nearly all modern fighter jets have a very swept back leading edge as it blends into the fuselage - e.g. the F18 Hornet or F16 Falcon - it helps the vortex to form over the wing at an early stage. Raising the nose increases the size of the vortex, lowering the pressure and enabling the aircraft to fly slower. You can actually see the vortex as Concorde touches down and the puff of smoke from the tyres is caught in it. The very high nose attitude on landing narrows the gap between the wing and ground and causes a high pressure cushion under the wing just before landing which arrests the rate of descent, and this may have been what Chartman was referring to.
As for the future of commercial supersonic flight, with nothing on the drawing board, and with the incredible lead times of these complex projects, it looks like it will be at least 30 years before we see it again at the earliest. Who would have thought that at the time of the lunar landings in 1969 that 34 years later we would have no plans whatsoever to go back there or to go on to Mars. Talk at the time was that it would be the moon by 1969 and Mars by 1980. The 1968 film "2001 a Space Odyssey" envisaged lunar bases and nuclear powered space craft capable of taking men to Jupiter by the millenium. Such was the optimism of the 1960's as explained by trader333 above. Even the younger members of this board are unlikely to see this in their lifetime now.
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