fw 190a5 flight model

[Janosch]

The structural limit before permanent deformation on these fighters was typically a factor of two, so way beyond the assumed loads: 14 Gs on the Me-109G and 13 Gs on the P-51, so there is plenty of room for the structure to bend more than the assumed 6 or 7 Gs of assumed actual wing bending load.

No way you could pull anywhere near 14 Gs without wings coming off!

Your comment that weight cannot be added to just because an object is in flight seems on its face nonsensical: If I press down, say through leverage, with a fifty pound force on an 80 lbs block, flying or not, it will then become (for all practical purposes) 30 lbs "heavier" than the "heavier" 100 pound block, flying or not... I cannot fanthom what you fail to get in this...

Weight or mass of object doesn't change in normal circumstances... only the fuel consumption changes it. When speed approaches the speed of light, only then mass goes infinite. Wasn't it Einstein who said something like that?

This compiling is very rewarding for me, as the accounts do clearly demonstrate the superiority, in low-speed turns at any altitudes, of both the P-47D and the FW-190A to the Me-109G

Too bad it doesn't actually prove anything, e.g. that Me-109G would really turn worse than a P-47D. In such fight, the 47 loses... most notably because it's heavier.

[MaxGunz]

Originally Posted by Gaston

Your comments show little understanding of what I said.

That's because your made-up nonsense cannot be understood in any logical sense.

I said the wings on these old aircrafts ALWAYS bend more than previously assumed for a given horizontal turn,

SOURCE?

since wind tunnels do not imitate a curved trajectory, and wing bending on these old nose-pulled types was never actually measured in turning flight (dive pull-outs measurements would not count because of the prop unloading in the dive)...

SOURCE?

And when did they put full size planes in WWII wind tunnels?

The structural limit before permanent deformation on these fighters was typically a factor of two, so way beyond the assumed loads: 14 Gs on the Me-109G and 13 Gs on the P-51, so there is plenty of room for the structure to bend more than the assumed 6 or 7 Gs of assumed actual wing bending load.

Ass-uming the pilot can take any 13 or 14 G's beyond momentarily, less than a second.

If you don't understand that more wing-bending applied differently among types can play havoc with wingloading assumptions, and is important for the wingload hierarchy between aircrafts, I don't know what to say to that... Your comment makes absolutely no sense.

SOURCE?

Something besides in the mind of Gaston, please!

Even Glider would readily agree that if the wingload is added to unevenly across types, it would change the wingload hierarchy between types, which is what this is all about...

A new of line of unsupported BS?

Your comment that weight cannot be added to just because an object is in flight seems on its face nonsensical: If I press down, say through leverage, with a fifty pound force on an 80 lbs block, flying or not, it will then become (for all practical purposes) 30 lbs "heavier" than the "heavier" 100 pound block, flying or not... I cannot fanthom what you fail to get in this...

Because it is complete physics-violating BS to say that you can from within the plane press down and make the plane heavier. You are now in the realm of violating the 2nd Law of Motion in Grand Crank Style. The classic non-demo is a 150 lb man pulling his bootstraps with 160 lbs force and expecting to lift himself off the ground.
Pressing down on a block that you are not standing on does not apply to pressing down on a plane by any means within the plane. That does not include changing the controls that affect air flow (external to the plane) which does not change the weight of the plane regardless.

I never said the FW-190A produces more lift at lower speeds and lower Gs than at higher speeds and higher Gs: I said that the "extra" load is proportionately greater at lower Gs, because it is not changed by speed but by power, and the power stays the same since it is assumed to be at the same maximum in all turns, high or low G, for simplicity's sake...

Which is BS. Power/thrust does not change wingloading.

So it is logical that an aircraft that has less of that "extra" power load (because of better leverage over a shorter nose) will benefit more at low speeds where the power is "larger" compared to the "pure weight" G loads... But at high G loads the actual mass of the aircraft is multiplied by the Gs, while the power is assumed the same, so the lighter aircraft benefits more than the heavier aircraft from high Gs, and the "power leverage load" is proportionately smaller to the "real" G load, so having a big advantage in "leverage power load" (like the FW-190) is less significant and becomes less and less significant as the turn becomes more and more tight beyond what is sustainable in speed...

At high Gs, weight matters increasingly more than power, everyone should be able to understand that... Hence the FW-190A's turn performance goes down relative to lighter fighters when Gs go up beyond a sustainable speed... Which is exactly what can be observed in innumerable combats...

There is no way, if you accept the premise of an extra load on the wing due to power, that any of this is debatable...

So given that physics is wrong and your joke ideas are right, you have a muddled 'point'.

As for the issue of where the extra lift comes from, it is a thorny issue, but since we don't know how much those wing actually bend in turning flight (thus with assymetrical air inflow), who can say the extra lift is not there?

Not you, that's for sure. How far the wings could cantilever without deforming was tested and known. They did test structures to destruction but then engineers did and still do things like that.

If there is extra wing bending, and if it changes with power level, then it means that the extra lift is there, and it is power-related, regardless of what our other assumtions are...

If... Enough ... nothing real, no source... Then It Means, whatever you decide in your fantasyland ... Other Assumptions and non-factors from non-facts....

Note that I attribute the load to the leverage of the power coming from a long nose, so that is why more recent studies of very advanced jet fighters completely failed to uncover this extra power load... The existence of such in-flight wing bending tests seems not to overlap further back than the early jet age... Current warbird operators do not use wing strain gauges in flight, at least not routinely...

What recent studies This Time? SOURCE?

I also think that one of the features of that extra "nose power" load is that the width of the prop surface creates its turn assymetry through increased thrust in the disc's inside turn half, which increased thrust could help "mask" the inevitable extra drag needed for that extra load on the wings...

And now you're back to the old "Stress Risers" without actually using the words This Time Around. But it's the same unsupported stuff as before.

What is your SOURCE? Do you hold a model plane and imagine this while making zoomy sounds?

By saying "wing bending cannot create extra lift", you are confusing cause and effect... The cause of the extra lift is obviously complex if it was hidden for 100 years (but it isn't so outlandish if you include the "gradually increasing" assymetrical inflow of air in a turn, which is not duplicable in wind tunnels)...

Obviously. They could predict what happened quite well without knowing the secret Gaston Force that does absolutely NOTHING. Since it had NO EFFECT they never knew it wasn't there! Oh, those Idiots!

If your ideas were right then perpetual motion would be possible.

[Herra Tohtori]

I will create a free-body diagram of the (relevant) forces affecting a flying aircraft in a turn when I have time for it.

I'll just note a few key factors here.

1. Maximum power of the engine is irrelevant at slow speeds.

If you were familiar with definitions of work and power you would understand this; I can show you why this is so but I don't know if you would understand the mathematics (it's reasonably simple but it does involve some grasp of differential calculus). For now, suffice to say that when an aircraft travels slower, the engines do less work per unit of time, which means by definition that their power output is reduced. Aircraft engines reach their peak power output only at maximum speed of the aircraft (same actually applies to automobiles!).

2. There is a component of thrust that is directed toward the centre of the turning circle.

This can easily be defined as

Fc = F * sin α

where F is the thrust of the propeller disk, and α is the angle of attack. Let's assume that α cannot be larger than critical angle of attack; α ≈ 15°

At critical angle of attack (maximum turn performance at any speed), the thrust toward the centre of the circle would be

Fc = F * sin 15° = 0.25 F

Hence, we can say that at most, only about quarter of the total thrust of the engine is directed inward and thus assisting in the turning radius. This, however, applies to all aircraft, not just FW-190 so it doesn't really help your point... especially as we get to point three.

3. Since we now know the assisting centripetal component of the thrust force, we can determine the assisting centripetal acceleration:

a = Fc / m = 0.25 F / m

since F/m is the thrust to mass ratio of any aircraft, we can DIRECTLY say that the thrust to mass (more commonly incorrectly expressed as thrust to weight ratio) does affect the turning performance.

Moreover, this simple exercise of physics shows us that aircraft turn harder when their engine produces more thrust.


Confusingly (or rather, not) we know that Spitfires have better acceleration and climb rate than FW-190, which means Spitfires have better thrust to mass ratio.

Which means that the expectation of the theory is that Spitfire engine can assist in turns more effectively than that of FW-190... which doesn't really help your case.


4. Quantitative analysis

How, then, does this centripetal acceleration produced by the engine thrust compare to the centripetal acceleration produced by the lift of the wings?

Well, again, simple exercise. If we assume that at certain speed v, the aircraft would be able to do a 3g turn, that means the wings produce enough force to produce 3 g's worth of acceleration (they can easily produce much, much more force up to the limit of their plasticity, in which they deform permanently, but since the discussion is about low speed performance let's keep it at that flight regime).

By contrast if we look at the maximum acceleration that the engine thrust can produce, we can immediately see that the thrust is about an order of magnitude smaller force than the lift of the wings. It's difficult to actually determine the thrust of these aircraft; however we can get some results by looking at how well they climb vertically. None of the WW2 aircraft can maintain their velocity (or increase it) in vertical climb; this means that the propellers produce less force than the aircraft's weight - their thrust/weight ratio is smaller than one.

At thrust/weight ratio of one, the engine could give the aircraft exactly 1g of acceleration. Since these aircraft get nowhere near that, let's be generous and assume the acceleration at standing start could be.. let's say 0.5 g's (it is probably less than this, but oh well...).

Now we can determine the centripetal acceleration by thrust:

ac = 0.25 a = 0.25 * 0.5 g = 0.125 g


What does this mean? Well, if a gliding aircraft at speed v can pull a 3g turn, with full power it could pull about 3.125 g turn (increasing it's turn rate and decreasing turn radius).

This applies to all powered aircraft, and the defining factor is the aircraft's thrust to mass ratio - or, unloaded acceleration by engine thrust alone.

Multiplying this by the sine of angle of attack you can directly get the assisting centripetal acceleration.

a(engine) = 0.125 g

a(lift) = 3 g

we can see that the assisting engine thrust is, at best, about 4% of the lift.

At high g-load the ratio further decreases because you can't pull critical angle of attack at high speeds - which means that most of the thrust is directed forward.


Now, if you're looking at two different planes with different thrust/mass ratios - yes, the plane with better thrust/mass ratio will provide more assisting centripetal acceleration.

However now you need to consider that the thrust/mass ratio of these aircraft had relatively small variations. What you will find is that the overwhelmingly deciding factor in turn rate is the lift/mass ratio rather than engine thrust. You might find small differences in the assisting thrust - let's say that one aircraft's engine might assist at 4% of lift, while another aircraft's engine might assist turning at 5% of the lift... but this would already mean a quite hefty 25% thrust/mass ratio difference!


Here we have shown that the engine thrust is primarily responsible for maintaining the cornering velocity (overcoming drag), and wings are primarily responsible for actually turning the aircraft.

I don't expect Gaston to really comprehend any of this, this is more for the benefit of others.

I'll make that free body diagram as soon as I can... now I must get going to school.

Toodles!

[FC99]

Originally Posted by Gaston

I have asked years later of the site owner, surnamed Hitech, to tell me where to find this thread, titled "FW-190A veteran experience" (it went on for about 4 pages the last time I saw it): He actually claimed not to remember it... It is of course deleted from the archives, and he knows nothing about it...

I guess everything the "real deal" had to say just exposed too harshly how current simulations, his and others, were a big pile of claptrap...

But apparently, after all my threads, the Aces high FW-190A got quite a bit better...

Please, post this on Aces High board, I'd like to read Dale's comment when he realize that his FM is "Gaston approved"

Originally Posted by Gaston

The structural limit before permanent deformation on these fighters was typically a factor of two, so way beyond the assumed loads: 14 Gs on the Me-109G and 13 Gs on the P-51, so there is plenty of room for the structure to bend more than the assumed 6 or 7 Gs of assumed actual wing bending load.

Structural limit for deformation is the one listed in manual, for fighter planes, safety factor was typically about 1.5 so plane with 8G limit will be expected to survive 12G. Between 8 and 12G plane will suffer permanent damage and in case of repeated over-stressing it will break even at values under 12G.
You can see in attachment where is the expected wing failure for one WWII fighter.

Originally Posted by Herra Tohtori

I don't expect Gaston to really comprehend any of this, this is more for the benefit of others.

There is no aviation board where Gaston didn't post his alternative aerodynamics theories, if he was capable of learning anything he would learn it long ago. He is not even funny anymore, it's just sad.

[Treetop64]

This is entertaining. Even in college, I've never seen anyone who believes their own BS as much as Gaston.

[Rot Bourratif]

Trolls...

Ah well, I remember having to give up on a mechanical science forum because of one of those.

He kept arguing that imperial measurements were far superior to metrics and people were foolish enough to argue with him.

There is only one response to Trolls: ignore them.

Here is some counseling:

http://www.wikihow.com/Recognize-a-T...n-the-Internet

http://trollpolice.com/trolls-and-cyberstalkers/

~S~

[Woke Up Dead]

So Gaston, if I understand correctly, your theory is that these previously unnoticed and/or not measured and/or unmeasurable forces you describe are so significant that they make the P-47 and the 190 into good low-speed turners, even though all the known, measurable, and measured forces predict the opposite to be true. Correct?

[Glider]

Gaston
Please don't quote me as agreeing anything you say, without me first, actually agreeing.

No need to do vast research, just pick one combat report from any list and we will see what happens in the ten either side.

Nice, simple and easy for anyone to check.

I strongly suspect that you have not found a suitable example and are going to try and blind me and everyone else with vast amounts of data that will mean nothing

[Igo kyu]

Originally Posted by Glider

No need to do vast research, just pick one combat report from any list and we will see what happens in the ten either side.

He's writing his own list with hand-picked examples (which will all appear to agree with him), he almost said as much in that post.

[MaxGunz]

Based on criteria of fitting the hypothesis in some manner.

Don't say "any" list because you won't get just any list.

Just because there's accounts on a web site doesn't mean there's been no selection of which accounts are presented. Just for example: the pilots who did not come back did not make combat reports. That alone is data selection.