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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."
I'd want them to work on the technology a bit before this happened though. Wouldn't want the plane suddenly falling apart way up in the sky.
GERONIMO!!!!
...in november's issue of scientific american entitled "Flying on flexible wings"
you may find the Higgs in this signature.
So it will be a long time before you catch a plane and watch the wings disappear by looking through the window.
Not if you fly USAir!
You know...
...that thing had better be sporting a Decepticon insignia.
The coolest voice ever.
Anything that bends that isn't organic tends to eventually weaken and break. And the organic stuff only manages to keep structural integrity through constant ongoing repair.
The maintenance up-time required for a flexing wing will probably be ridiculous, unless it contains self-repairing abilities.
Airplanes, whether manned or unmanned, need to travel at various speeds.
Sweet Zeus, what a revelation.
I also did not realize that it would ever be possible to make wings disappear by looking through a window.
Where's my flying car?
There's .... oh, no, it's just changing shape again.
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.
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
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?
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.
Look at the difference between the position of the wingtip durring taxi on the ground and cruise. Many larger aircraft (747, 777, etc) have a difference nearly 5 ft, and this is normal conditions. The wings also have to be designed to take much more durring turbulence and emergency manuevers.
If you want to see some crazy stuff look around for wing flutter. This is where the wing hits a natural frequency and crazy stuff starts to happen. One of my proffessors use to do research in this area with NASA and has some crazy stories.
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.