Wing flex/over wing vapor.

Not sure where people are learning their English but little flex =/= no flex. I would think logically no flex = no flex and little flex = a little flex.

My point was it doesn't flex much but it does flex. Whether or not ED wants to commit resources to simulate that is up to them and really, who cares? Not a deal breaker if they don't put wing flex in.

But people making the argument that flexing a little = not flexing at all is absurd.

If someone shot your toe off and then tried to make the argument that they, in fact, didn't shoot you at all, simply because they shot you "a little bit" and a little bit = not at all, nobody would buy that, I'm betting.

Somebody who works with A-10's in real life tells you they do not flex. I'm not sure why you think you know better.

Because it's hard to believe that someone without basic physics knowledge would be allowed to work near $multimillion flying machines.

Somebody who works with A-10's in real life tells you they do not flex. I'm not sure why you think you know better.

So I should believe some random person on forum and not my own eyes?

Cantilever beam - single load - deflection

Maximum Reaction Force

at the fixed end can be expressed as:

RA = F

where

RA = reaction force in A (N, lb)

F = single acting force in B (N, lb)

Maximum Moment

at the fixed end can be expressed as

Mmax = MA

= - F L

where

MA = maximum moment in A (Nm, Nmm, lb in)

L = length of beam (m, mm, in)

Maximum Deflection

at the end of the cantilever beam can be expressed as

δB = F L3 / (3 E I)

where

δB = maximum deflection in B (m, mm, in)

E = modulus of elasticity (N/m2 (Pa), N/mm2, lb/in2 (psi))

I = moment of Inertia (m4, mm4, in4)

b = length between B and C (m, mm, in)

Stress

The stress in a bending beam can be expressed as

σ = y M / I

where

σ = stress (Pa (N/m2), N/mm2, psi)

y = distance to point from neutral axis (m, mm, in)

M = bending moment (Nm, lb in)

I = moment of Inertia (m4, mm4, in4)

The maximum moment in a cantilever beam is at the fixed point and the maximum stress can be calculated by

σmax = ymax F L / I

I've seen the videos from the previous posts and, yes, I do see wing flex (as in some cases it's rather obvious.) The modulus of elasticity of pure carbon (in diamond form) is 700 - 1200 GPa. That would flex under the right conditions. So, all materials flex. Can you see it with your naked eye? In some materials, of course. It some others, no so easy.

That said, in the most obvious example video link from previous posts, it would be possible to take a freeze from from one frame, skip forward a bit to catch the flex range, measure it in pixels, then using dimension data from actual A-10's, back calculate how many inches of flex the wing was sustaining in that video at that time frame. We could also calculate what the modulus of elasticity of the entire wing box was from just that pixel analysis. But, I've got a pizza coming out of my kitchen oven that needs to be eaten forthwith.

You do the math.

:)

So I should believe some random person on forum and not my own eyes?

I assume we are talking about Snoopy? Not exactly a random person on the forums.

I assume we are talking about Snoopy? Not exactly a random person on the forums.

So, is he a structural engineer? Or maybe material physicist? If he is, his argumentation is very weak - non-existent. It doesnt flex because he says so? Classical fallacy of appealing to an authority.

=mac= provided real arguments.

Every wing has some degree of elasticity. If it didn’t, it would snap. Hog wings will obviously move a little but in comparison to a Viper or a Hornet, they may as well be called ridged.

Exactly, elasticity is necessary to avoid breackage.

As the movement in the cockpit noticeable between the front panel and the canopy bow at

Anyway for me, there's some minor movement in the wing, no doubt.

How about pylon flex? And the flex of the HUD?

As you said, everything flexes.

I think the point being made wasn't that it doesn't flex, but rather that it doesn't flex enough to warrant modelling. Whereas the flex of some other aircraft is characteristic, the A-10s flex seems to be so minor as to not exist. Ever notice how the glare shield in hornet bounces and wobbles all over the place irl, but in DCS its solid.

So, is he a structural engineer? Or maybe material physicist? If he is, his argumentation is very weak - non-existent. It doesnt flex because he says so? Classical fallacy of appealing to an authority.

 

=mac= provided real arguments.

And now we understand why so many SME's have abandoned this community. I'm sure =mac='s "real arguments" about simple beams applies fully to this complex situation.

And the word you are looking for is Metallurgist I believe

And the word you are looking for is Metallurgist I believe

We Metallurgist have knowledge about molten metals. Structural engineer is the better word.

Well since Snoopy works with Hogs on a daily basis. I'd say he might be a good person to ask. AFAIR he's been at it for quite a few years too..........

Because it's hard to believe that someone without basic physics knowledge would be allowed to work near $multimillion flying machines.

A lot of us vet's don't do physics my friend. Sure we have an idea but mostly no. I've worked around and been responsible for multimillion dollar aircraft my entire life. I'm no genius but I understand them. Sometimes experience is key. Some of us are not Rhodes Scholars but we are not idiots. We are Operators. I'd take Snoopy's word for it. And I do not know him at all in person, I just read what he says just on the forums. Here in 2020, I have a new found love for the A-10. I'm starting to miss Active Duty because of DCS lol

Peace

A lot of us vet's don't do physics my friend.

In "basic" I meant that you should know that dropped wrench will hurt your foot :) Same as you're smart enough to understand that metal structures flex.

We don't have to take anyone's word for it when we can see it ourselves. That conversation ends with "Of course I not meant it doesn't flex at all, LOL, only it does flex very little". Then we can only discuss is it worth to simulate this.

What missile is this? (inboard one.)

What missile is this? (inboard one.)

ACMI pod

https://en.wikipedia.org/wiki/Air_combat_maneuvering_instrumentation

This thread was created in the wishlist section for the A-10C 2, the first post mentions the title "Wing flex/over win vapor." Although I appreciate people "defending" me it isn't needed, everyone is allowed to have their own opinion on this subject that being said....

As the title says, though I don't know if I've ever saw over wing vapor on a A-10 but it should happen in certain conditions, right?

My reply...

Vapor yes, flex no.

Folks obviously are reading into a four word sentence and insinuating I stated the A-10 wings do not flex. My reply was to a wishlist post concerning wing vapor and flex. Aka no I don't wish for wing flex but yes to wing vapor. I even clarified the vapor wish later by stating that vapor doesn't happen as often in the real world as it does in DCS.

So for clarification (sorry if I'm not a structural engineer and not posting mathematical equations) yes A-10 wings do flex. BUT in my opinion, based on what I've seen over my career and talking to pilots on the subject (take it with a grain of salt if you'd like), they don't flex enough to really be noticeable so in my opinion I think ED should focus their efforts on things that matter and not something that would be so small you wouldn't notice or so overly done it would be cartoonish.

@Snoopy: You're right, that's not what you said. I've never read your post, just reacted to this guy who really miss-presented your words:

Somebody who works with A-10's in real life tells you they do not flex. I'm not sure why you think you know better.

I reacted to this not because I want wing flex or not but because this is such a bad attitude that advocates blindly believing anyone over thinking with your own brain.

I'm sorry for inconvenience.

In "basic" I meant that you should know that dropped wrench will hurt your foot :) Same as you're smart enough to understand that metal structures flex.

 

We don't have to take anyone's word for it when we can see it ourselves. That conversation ends with "Of course I not meant it doesn't flex at all, LOL, only it does flex very little". Then we can only discuss is it worth to simulate this.

I see your point

I'm sure the wings flex but do they do it enough to see? I'm not sure how important this is?

I didn't notice a lot of flex in the video but the wings did move when the gun was fired. More a vibration than flex.

ACMI pod

 

https://en.wikipedia.org/wiki/Air_combat_maneuvering_instrumentation

Thanks.

I'm sure the wings flex but do they do it enough to see? I'm not sure how important this is?

 

I didn't notice a lot of flex in the video but the wings did move when the gun was fired. More a vibration than flex.

Personally I thought it was more distortion from the camera lens.

Personally I thought it was more distortion from the camera lens.

Probably right.