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Morphing Plane Wings for Efficient Flights
Roland Piquepaille writes "Airplanes, whether manned or unmanned, need to travel at various speeds. For example, a surveillance plane needs to fly fast to reach its destination point. Then, it needs to reduce its speed to achieve its surveillance mission. But with its fixed wings, it doesn't offer the same level of efficiency during these two phases. That's why Penn State engineers have devised airplane wings that change shape like a bird and have scales like a fish. Right now, the team has only built a tabletop model. So it will be a long time before you catch a plane and watch the wings disappear by looking through the window. This overview contains more details and references, including a couple of images describing the work done so far."
...in november's issue of scientific american entitled "Flying on flexible wings"
you may find the Higgs in this signature.
Yeah, but this is different. I caught the idea in a Popular Science a while back.
The difference is that the F-14 moves the physical wings to be more efficient. The wings in this article actualy change shape. i guess a good thing to compare it to is the liquid metal guy from T2. He could change his bodies shape on demand. That's what this is. I guess they finally figured out how to keep it stable with the immense pressures, forces, and speeds wings are subjected to.
My guess is that this "next greatest thing" isn't the answer either, but almost anything is better than a swing wing.
Is it fascism yet?
The U.S. F-14 and F-111, European Tornado, and a bunch of Russian Tupolev and Sukhoi models have had variable-geometry wings for decades. This is hardly a new concept -- just snazzier ways of doing it.
In principio creauit Linus Linucem.
The Concorde wing is static, except for the obvious movable control surfaces. Does not change shape in flight.
Its the cross section of the wing that changes, not the angle or length of the wing.
God, root, what is the difference?
I wonder if Slashdotters ever read the fucking article.
They're talking about the use of memory alloys for a flexible wing which, in tandem with the segmented skin, will allow the wings to be deformed in-flight to adjust its aerodynamic properties. Think of it like having a wing with hundreds or thousands of flaps which could be raised or lowered in sections to change the profile of the wing to fit any situation.
Oh, remind me: where'd you study aeronautics?
That would be a trip to the wrong place. Penn State is not the University of Pennsylvania
the formal term for this is called "aeroelastic tailoring". the wright brothers did use it to control the roll of the wright flyer, they called it "wing warping", it was their solution to steering in 3 dimensions. it was so difficult to do with the stronger wings that they started using ailerons instead.
as for the f-14 and variable geometry wings, it's not quite the same. moving the wings back and forth help with things like shock waves and control fading/reversal at high speeds.
we use the math now to determine if the wings of an airplane will rip off without warning, a phenomenon called "divergence". as for the complicated maintence issue, every plane goes through this, although they don't actively change their wings. if you watch the wings the next time you fly somewhere, you'll see they bounce up and down. the math is done during construction and testing to make sure that the airplane can deform as it needs to and still stay in the air.
who says college doesn't teach you anything? now if i could just pass the final in this class on monday...
I have read about a very similar patent in a Russian techincal journal ("Yunii Tehnik" the guys from former USSR will know what I am talking about) back in the early nineties. It was a proposal to change the shape of a wing using a compressed gas and some sort of a baloon inside the wing. The wings on some of the supersonic planes already can change their angle relative to the fuselage and that would have allowed it to change the profile (cross-section) too. Thick profile - good at slow speeds, thin - at supersonic. But don't quote me on this, I am not an aerospace guy, just remembered that article for some reason.
Rubber bags are correct. Just like the fuel cell bladder in most forms of racing you can think of. Normally reinforced with kevlar and othe fibers to make them punture resistant. They just plain work.
Professional Politicians are not the solution, they ARE the problem.
During landing, take off, turbulent flight... the wings shake and shudder a bit. In fact an older issue of AIR International detailed the wing flex testing of the A380, which showed that it could adequately handle wingtip deviations of several feet. My point is that modern aircraft materials are already designed to withstand the inevitable flexing caused by normal flight. We don't see wings just disintegrating after rough flights, do we?
Modern aluminum alloys with a carbon fiber/resin infrastructure could handle these well known aeroelastic stresses. One shouldn't just lay a blanket of assumption saying that any non-natural bending material that retains strength is impossible, though handling the problems of aeroelasticity remains a very active research area.
Actually, you're right. I'm just joining the discussion, so I don't know if anyone's mentioned it, but there was an F-111 test vehicle which included variable-camber, as well as variable sweep, wings. It was part of the AFTI program, which also related to some axis decoupling (for lack of a better term) work with a modified F-16 with canards. This particular project was known as the Mission Adaptive Wing.
organic? check
fatigue resistant? check
most Al alloys have no endurance limit and thus will always eventually (maybe in 1 min or 10000 years) fail by fatigue if they do not fail some other way first
Even if this isn't exactly the same application as the Wright's Wing Warping, the point of both is to change the aerodynamics of the wing by changing its geometery. This is just the latest in a long line of attempts. In the 1980's NASA came up with the scissors wing to address exactly this problem -- swept wing for the fast transit to the station point, straight wing for loitering on station. In the 1990's Boeing won a contract to re-wing a bunch of Navy jets with flexible composite wings -- with no slats, flaps, or ailerons.
If all this should have a reason, we would be the last to know.
This project looks like much of the same. Modern aircraft wings are monocoque, and have very little internal structure (although the space may be filled by other things like fuel tankage). These wings would require a lot of heavy internal structure to accomplish the effect, thus losing the benefits of the more efficient airfoil. Plus, the MMHFH ratio must be pretty awful with hundreds of little actuators.
They'd also make a much poorer fuel tank...
On top of that, what are the failure modes? What happens if one of those actuators fails in the middle of a shift? Does the wing rip itself apart?
Even if the wing stays in one piece you have the problem of the two wings producing differing amounts of lift and drag. If the roll and yaw control surfaces can't cope with this then the plane is likely to fall out of the sky. (Probably in bits since the resulting areodymanic forces will tear it apart.)
I'm not sure I'd want to fly in a plane with flapping wings, but morphing surfaces might be a boost to these guys, who are working on ornithopters (and must be avid Frank Herbert fans). The video of their 1/4 proof of concept in flight is pretty interesting.
They're not fish scales, but I Think it's been done before. Granted that doesn't help efficiency, but I think these do.
What the heck is a 'sig'?