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Old 07-28-2019, 03:31 PM   #41
Sirius
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Which means the more reduction, the easier the bending may occur from forces. Not all bending of wings on aircraft are linear, not even the Tomcat which has more extremity around the edge as well.
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Old 07-29-2019, 09:02 AM   #42
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Quote:
Originally Posted by Sirius View Post
I'm going to side with the 3rd party developer here who actually knows what he is doing.



Wing flex is a result of lift forces that occur on the wing. Every aircraft has an amount of wing flex but it is barely noticeable. More lift occurs around the wingtip section than the rather general area, that when pulling G forces it causes a significant bend. While you may argue that it is visually incorrect, the "bend" or flex of the wings is dependent on the wing's internal structure, as well as the composition of materials used.



The 1st example is what we are observing in DCS with the edge of the wing structure bending (I-beam in this case) becoming more extreme the closer it is. The 2nd is what you're trying to observe.







Very nice animations!

I do, however, think that OP is trying to observe the first case.

OP claims that there is zero displacement of the loaded wing until halfway out from the tip. If that claim is true, and I haven't tested it myself so I cannot vouch for it, then there's a problem or "problem", if you will.

Because physics, there's no way for a wing to not bend until halfway to the tip. Thus, if you are trying to prove that OP is wrong, you should prove that the wing DOES bend in the inner half, albeit very little.

Now, because no part of a real aircraft is a rigid body, there should of course be all sorts of bending going on. E.g. the nose should droop when pulling Gs. I don't think that's modelled, and that's fine with me. I am happy that the wings bend at all.
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Old 07-29-2019, 11:04 AM   #43
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The Hornet's wing is also not a one-piece structure. There is a hinge 2/3rds of the way down which no doubt has reinforcing either side, that surely affects how it flexes?

In any case if I see the wing tips flexing a bit when I look sideways I'm happy.
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Old 07-29-2019, 01:25 PM   #44
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Exactly. Watch the video I provided earlier - it has a section showing the composition of the F-18 wing. It is not a simple straight girder profile for a spar, it is a series of tapering box sections enclosed by the skin, that are far more rigid on the inner section. Glider wing it is not.
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Old 07-29-2019, 02:06 PM   #45
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Quote:
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It is not a simple straight girder profile for a spar, it is a series of tapering box sections enclosed by the skin, that are far more rigid on the inner section. Glider wing it is not.
You are completely missing the point. A modern glider is usually also a stressed skin, (multi) spar design and the same principles apply, the same load application etc.
Again, if you look at the glider wing video you will notice the the bending occurs the most at the outer part, and there's (almost) no bending at the root.
It's the same on the F/A-18, the 787 'plastic' wing or a 'classic' B-52 wing.
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Old 07-31-2019, 05:14 PM   #46
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You are completely missing the point. A modern glider is usually also a stressed skin, (multi) spar design and the same principles apply, the same load application etc.
Again, if you look at the glider wing video you will notice the the bending occurs the most at the outer part, and there's (almost) no bending at the root.
It's the same on the F/A-18, the 787 'plastic' wing or a 'classic' B-52 wing.
I don't think I am completely missing the point. A modern glider and other very slender wings that you mention are not designed to carry 2000+lb bombs and counter significant G loads. It really is not the same design rationale. Have you ever jumped up and down on a modern glider wing - why not? It would crumple. Have I done so on a (maybe not quite so modern) naval strike fighter wing? Yes. Did it Break - No. Why not? It was designed to be as rigid as possible to counter the stresses involved in dropping bombs at high speed & possible high G, not cruising around sedately at altitude.
Whatever. the case, I don't think the structure of an F-18 wing inner section looks remotely flexible - it is after all part of the fuselage, not something pinned on like your glider example, and until someone who actually flies the things, or designed them says otherwise, I'm inclined to think what we have looks reasonable, if not exactly correct.
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Old 07-31-2019, 05:56 PM   #47
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Quote:
Originally Posted by mkiii View Post
1. A modern glider wing is not designed to counter significant G loads. It really is not the same design rationale. Have you ever jumped up and down on a modern glider wing - why not? It would crumple. Have I done so on a naval strike fighter wing? Yes. Did it Break - No. Why not? It was designed to be as rigid as possible to counter the stresses involved in dropping bombs at high speed & possible high G, not cruising around sedately at altitude.

2. I don't think the structure of an F-18 wing inner section looks remotely flexible...I'm inclined to think what we have looks reasonable, if not exactly correct.
1. Are you sure? E.g. the Swift S-1 wing is designed to take much more stress than any of your fighters, the ultimate load limit is +15G and -11.2G. (you could jump up and down on the wing all day long)

2. That's what I'm saying/writing the whole time!

Last edited by bbrz; 07-31-2019 at 06:03 PM.
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Old 08-01-2019, 12:35 AM   #48
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I wondered how long it would take you two to realises you were furiously agreeing
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Old 08-01-2019, 03:53 AM   #49
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Quote:
Originally Posted by Weta43 View Post
I wondered how long it would take you two to realises you were furiously agreeing
But that's apparently accidentally, since we have differing knowledge about wing design.

Last edited by bbrz; 08-01-2019 at 06:08 AM.
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