I hope R.Mackey drops by for comments as he is likely more familiar with the latest technologies and concepts that I am.
I just got back from a lengthy trip to Ecuador. No, I didn't cause the Forum meltdown. Fnord.
I'll explain this a little further for those who don't understand. The pseudo intellectual is accusing me of ignoring what he apparently thinks is viable technology in the form of a morphed wing. Well, morphed wing technology has been in use since the 1960's in the F-111, F-14, and later the B-1. [...] A significant note here is that this technology was only incorporated into COMBAT ASSETS. No Transport Category aircraft has this feature simply because it would be a useless, wasted expense for a dubious purpose.
There are, of course, many ways to "morph" a wing. Transport aircraft actually have quite a bit of variability, namely in their flaps. Fully retracted, the wing is most efficient at low angles of attack, and is optimized for high subsonic speed. Fully extended, the wing is most efficient (and controllable!) at fairly high angles of attack, increasing lift to the point that it can fly much slower. Efficiency and controllability are the two big ones.
Swept-wings in military planes have much the same effect, but there are other factors in play that make swept wings more valuable in these applications, among them stowage space (especially in the F-14) and responsiveness. The B-1B Lancer is designed to "dash" and that requires rapid configuration changes, not the slow and carefully choreographed sequence of a commercial plane on descent.
The poster at LCF is talking about using memory shape alloys to actually twist the wing to allow greater angles of attack, therefore enhanced maneuverability. Think of the way birds use their wings to change the angle of attack and it will help to understand the concept. Perhaps it is a viable concept, perhaps not. It has been almost 7 years since 9/11 and if there were an aircraft of this type of design it would likely be common knowledge by now.
This has been studied extensively, and progress is slow. One of the most unusual "morphing" designs is the
Active Aeroelastic Wing research vehicle, building on
work done in the 80's using an F-8 Crusader that is now on a stick outside the Dryden visitor center. Anyway, what happens in this case is the wing itself changes shape, rather than just moving, to optimize performance. Quite interesting but complicated technology.
The AAW is the most advanced vehicle of this type in the world. Nothing resembling this technology has ever been fielded. Nor would it provide the capabilities the conspiracy theorists want in the first place -- the AAW is all about fuel efficiency, flutter reduction, control redundancy, and stability. This technology cannot possibly give you an aircraft capable of the radically tight turns they've proposed, and even if it could, survival of the pilot would be in grave doubt.
The most advanced viable technology in use today is "vectored thrust". That concept is incorporated into the F-22 Raptor. It would likely not be a viable concept in a Transport Category aircraft simply because of wing mounted engines versus fuselage mounted ones. Again, it would be virtually useless in anything other than a Combat Asset anyway and no sane responsible person would even suggest it.
Vectored thrust will help with the control authority problem, because it lets you use thrust to spin the aircraft around rather than ailerons and elevators. Theoretically the engine inlet could be designed so that it wouldn't stall until after the control surfaces did, but in practice both will happen if you push it hard enough.
However, even vectored thrust cannot give you such absurdly tight turns. At best you might get 1.3
g out of the engine, compared to 9
g sustained which is available from aerodynamics. And that's in a lightweight, overpowered fighter aircraft. The idea of vectored thrust providing multiple
g of maneuver in something the size of a 757 beggars the imagination. At that point, rather than crash the Pentagon, you may as well hover over it and melt it into a puddle...