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Full Scale Foldable Wing Extensions

airbus.com

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Re: Full Scale Foldable Wing Extensions

#41

Post by stymaar »

SoftTalker wrote: post #28
sleepyguy wrote: post #23

>The Wing of Tomorrow programme is centred around creating longer, lighter, and more slender wings to maximise aerodynamic efficiency and reduce fuel burn. The wing extensions will be assembled at Airbus’ Wing Technology Development Centre in the UK and flight tested in Toulouse. I can't say for certain, but I believe Boeing may have explored this concept at some point. The idea would be to equip aircraft with mechan…

Military aircraft have done this for decades to deal with the confined space on aircraft carriers. It's not a new idea, nor any kind of new technology.

Do you have any aircraft on mind that can unfold its wing while flying? (I'm aware of variable-sweep wing which can reconfigure in flight, or foldable wings that will be fold on the ground before parking).

Re: Full Scale Foldable Wing Extensions

#42

Post by SoftTalker »

stymaar wrote: post #41
SoftTalker wrote: post #28

Earlier quoted context omitted.

Military aircraft have done this for decades to deal with the confined space on aircraft carriers. It's not a new idea, nor any kind of new technology.

Do you have any aircraft on mind that can unfold its wing while flying? (I'm aware of variable-sweep wing which can reconfigure in flight, or foldable wings that will be fold on the ground before parking).

I don't see in that article that they are planning to unfold them in flight. There is mention that "In parallel, Airbus UpNext is accelerating the eXtra Performance WING demonstrator, focused on developing a wing that can change shape during flight" but that sounds like a separate project.

My guess is that they will be folded after landing, and unfolded prior to takeoff, as other planes with foldable wings do, so that they can continue to fit in standard spaces in the parking/gate areas.

Re: Full Scale Foldable Wing Extensions

#43

Post by carabiner »

jsrozner wrote: post #32

It looks like you can get ~10-20% efficiency gain from these kinds of wings. https://www.technologyreview.com/2013/11/18/175391/folding-w... That's a meaningful improvement but not that big. Perhaps the limits to this kind of technology are ~50% fuel gain? https://www.technologyreview.com/2013/01/24/180345/hybrid-wi... We've got AI, but I'm still waiting on exponential technological gains. So far I've mostly gotten e…

This is a massive improvement for airliners where margins are a few %. Tube and wing configuration is already highly optimized. This is a physical problem with a hard limit. Can you make a sphere "exponentially" rounder?

Re: Full Scale Foldable Wing Extensions

#44

Post by dotancohen »

daemonologist wrote: post #25
moffkalast wrote: post #24

Earlier quoted context omitted.

Yeah that's uh, that's nothing. The orange part is supposed to be foldable somehow?

My read is that they're announcing a plan to build non-folding wings to test the geometry they would eventually want with folding wings. Which makes sense but isn't very exciting.

It's not just geometry, it's also where the mass is. And the rigid areas.

Aircraft wings oscillate during flight, the location (and movement) of mass within them (e.g. fuel) is critical to model.

Also, the location of the fold is likely less flexible (e.g. more rigid) than the remainder of the wing. This will greatly affect the dihedral angle of the remaining outboard portion of the wing.

Re: Full Scale Foldable Wing Extensions

#45

Post by dotancohen »

gnabgib wrote: post #4

Title: Airbus launches new flight test programme for Wing of Tomorrow ... doesn't look like there's any folding being tested here, just the resulting wing shape to see what the benefits might. Full scale foldable wings would be years off.

Not just the shape, but also the mass placement and rigidity. I explain this in another comment, I don't want to cut and paste redundant info here but keep scrolling and you'll find it ))

Re: Full Scale Foldable Wing Extensions

#47

Post by dotancohen »

jsrozner wrote: post #32

It looks like you can get ~10-20% efficiency gain from these kinds of wings. https://www.technologyreview.com/2013/11/18/175391/folding-w... That's a meaningful improvement but not that big. Perhaps the limits to this kind of technology are ~50% fuel gain? https://www.technologyreview.com/2013/01/24/180345/hybrid-wi... We've got AI, but I'm still waiting on exponential technological gains. So far I've mostly gotten e…

The first paragraph of your comment is very informative. The rest, not so much. I highly suggest editing the rest out.

Re: Full Scale Foldable Wing Extensions

#48

Post by _verandaguy »

jsrozner wrote: post #32

It looks like you can get ~10-20% efficiency gain from these kinds of wings. https://www.technologyreview.com/2013/11/18/175391/folding-w... That's a meaningful improvement but not that big. Perhaps the limits to this kind of technology are ~50% fuel gain? https://www.technologyreview.com/2013/01/24/180345/hybrid-wi... We've got AI, but I'm still waiting on exponential technological gains. So far I've mostly gotten e…

10-20% efficiency is enormous considering fuel is by far the dominant lifetime cost of operating an aircraft.

New fuels (SAF) and the technology to use them have been developed for less.

This is all to say nothing of the continuous work done over decades now to make aircraft more efficient; as these effects compound, intuition says that returns would start diminishing, so 10-20% is even more impressive.

Re: Full Scale Foldable Wing Extensions

#49

Post by metalman »

Orville Wright could have explained the reduced drag asociated with a higher aspect wing in 1902, perhaps useing his own terminology as airodynamics as a concept was still stuck in he and his brothers heads for the most part, but was very well known by 1910 and on up. Airbus should probably stick to structural engineering refinement, which they are rather good at, and not try and sell themselves as inovators, which they are not.

Re: Full Scale Foldable Wing Extensions

#50

Post by stackghost »

bilsbie wrote: post #15

What’s the purpose of doing this? (Site won’t load for me)

An airliner weighs a certain amount. In cruising flight, the lift on the aircraft is exactly equal to the weight (because it's neither climbing nor descending). Aerodynamic drag falls into 3 buckets: parasitic drag, wave drag, and lift-induced drag. Lift-induced drag is drag created by the wings producing lift.

Longer, thinner wings (higher aspect ratios) create less lift-induced drag for a given wing area, so ideally you want a super duper long and skinny wing, which will create less drag for a given amount of lift, and thus improve your fuel efficiency. Fuel is a massive portion of the total cost of operating an airliner, so there is a large financial incentive from the airlines to reduce fuel costs.

Unfortunately really long wings make airliners too wide to park at most airport gates, and in some cases too wide to taxi safely around obstacles, so they're experimenting with ways to make the wings fold and get a "best of both worlds" situation.

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