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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."
Actually commercial aircraft have to fly in many different conditions. Flying out of SFO is completely different then flighting out of DEN first in air density and then there are different weather conditions.
If Boeing or Airbus could offer an aircraft that could take off out of Denver on a hot day with the same payload capabilities as flying out of SFO on a cold day, they would have alot of buyers.
Once they're at cruising altitude you could change your wing to cruise settings for that maximum distance based on total weight and alter that durring the flight to minimize induced drag.
I cannot think of a single organic substance which doesn't eventually weaken and break. It's called death.
There's lots of bendy stuff that outlasts anything organic in the world.
One of the reasons that aircraft designers have moved away from swinging variable-geometry wings is the inherent weight and complexity penalty.
A swing-wing VG aircraft is inevitably heavier than a non-swing-wing aircraft. Gains from the more efficient aerodynamic shape are eaten up by having to support a greater weight of wing structure, which has bad effects on things like power-to-weight ratio and wing loading. On top of that, the greater mechanical complexity leads to a higher maintenance load, usually expressed in Maintenance Man-Hours per Flight Hour (MMHFH).
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.
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?
Move along folks, nothing to see here.
--Paul
The couple of times I've had a window seat on commercial flights (various Boeing 7x7s, and MD-80s) I distinctly saw movable flaps being used to change the shape of the wing during take-offs and landings.
Also, I would guess these wings aren't going to be very strong. I don't think they will safely be able to transmit the lift that they generate along their length to the body of the aircraft.
Might work for small UAVs though, since they're smaller, and lighter.
This is not a sig
I beleive this is the reason for having the overlapping metal plates or "scales." these would minimize the parts that would be required to move, and thus minimizing a failure. Now, if the wing could be constructed for less that it would cost to repair... Then instead of repairing we'd just replace. Probably for a passenger plan repairing would be a better idea, but for an unmanned spyplane? no need for self repairing abilities... unless of course your making real transformers.
face the world with eyes of fire.
Err, no.
If the stress put on a ferrous material is much smaller than the amount of stress that part can handle, then after a certain large number of cycles without failure you could pretty much consider the part unbreakable. For example, this is why it would be better to pick up a good set of seasoned connecting rods rather than a brand new set (assuming, of course, that someone hasn't abused the used conn rods).
Non-ferrous materials don't have this property. And of course, memory metal (usually nitinol) isn't ferrous. So I guess really I couldn't resist being pedantic...
Never fear! The USAF is here, and apparently they're Transformers fans.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Unfortunately that method doesn't change the surface area of the wing, only the shape. The method described in the article changes both.
Just another "isn't that theoretically cool - too bad none of this will ever come to fruition" story. Other examples:
- some amazing new display technology that allows us super-bright 300 DPI displays for $10 per square foot and can be painted onto walls
- some amazing battery technology that promises to power laptops for a week and ocean liners for a year
- some amazing new memory technology promising terabytes of ultra-fast storage that will usher in instant-on supercomputing
How about they invent a stupid pill so we can all take it and believe this technology will ever amount to anything?
Here's a new trick for you: read the article. They aren't talking about wing warping for flight control, they're talking about changing the wing shape (e.g. from swept back narrow to wide and short) to be optimal for different situations. A more flexible (literally) version of the variable geometry "swing wings" used on F-14s, F-111s, etc.
Complexity is Easy. Simplicity is Hard.
From the look of the model, tension is applied through strings or cables. As a pilot, I don't think I am ready to trust that till they start using a solid linkage. I had a rudder cable on a C172 snap once, and I really never want to try and land like that again. I can't imagine trusting my wings to that, especially my ailerons.
No ailerons, no getting home. Rudder and elevators won't steer a plane.
"Curiosity killed the cat, but for a while I was a suspect."- Steven Wright