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WrathofAtlantis

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the truth might lie somewhere in between, i think its completely possible that the 190 offers "decent" turning performance even at low speeds. the d-9 exhibits surprising low speed stability and its completely possible that the rate margin is low enough as to be wholly overshadowed by piloting techniques and errors.

however, this is not to say that on a mathematical basis, the 190 would not inevitably lose out in an indefinitely long circle fight. it's just that in practice fights are much more dynamic than static str contests because you're always on some sort of timer and that will constantly skew the balance of the equation.

 

the phrase you're clinging to "offering turning battle" does not in any way offer an explanation as to why it does so. "at minimum speed" is a great caveat here; any aircraft driven down to the slow end of the doghouse can "offer turning battle" because it's on the wrong side of the e-m graph and has no other choice when pressured.


Edited by probad
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The reality is if you think in "energy" terms, and in Gs much over 3-4 Gs (except on the vertical), you don't understand how these things fought differently than jets, and Shaw (plus the doghouse charts using "live" dive pull out data) bears much of the blame for that.

 

They were, horizontally, all about fighting within sustained Gs (3 G range), because, as the SETP found out to their surprise, in 1989, minimum speed for 6 horizontal Gs was maximum level speed, so the things could barely even MAKE 6 Gs for a split second in truly horizontal flight...

 

As for the physics, it's amazing that people graduate high school not knowing you can get more force out of something than you put in... Come on guys, this is part of being in a universe with shapes... The Greeks knew better than this 2400 years ago.

 

WoA


Edited by WrathofAtlantis
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  • ED Team
The reality is if you think in "energy" terms, and in Gs much over 3-4 Gs (except on the vertical), you don't understand how these things fought differently than jets, and Shaw (plus the doghouse charts using "live" dive pull out data) bears much of the blame for that.

 

They were, horizontally, all about fighting within sustained Gs (3 G range), because, as the SETP found out to their surprise, in 1989, minimum speed for 6 horizontal Gs was maximum level speed, so the things could barely even MAKE 6 Gs for a split second in truly horizontal flight...

 

As for the physics, it's amazing that people graduate high school not knowing you can get more force out of something than you put in... Come on guys, this is part of being in a universe with shapes... The Greeks knew better than this 2400 years ago.

 

WoA

 

The world are full of miracles for the people who avoided school lessons...

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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I give more details in these two videos:

 

The 1989 Society of Experimental Test Pilots test

 

This proves all the WWII/Korea prop doghouse charts were done with dive pull-outs G measures (safer and easier), unwittingly unloading the prop disc.

 

The SETP did actual G-measured HORIZONTAL turns in 1989: Full asymmetric load on the prop in a REAL turn, not unloaded prop in a dive pull-out like 40 years before...

 

For actual turning with a loaded prop, the doghouse shape is fiction, which is why slow sustained speed turns mattered a lot more than the comparatively unuseable high G energy burning turns... Hence vertical or horizontal fighters, but comparatively very little "energy" turning above 4-5 G: As the SETP points out, very short-lived high G values HORIZONTALLY, since the minimum speed to make them is top level speed...

 

The reality is if you think in "energy"

They were, horizontally, all about fighting within sustained Gs (3 G range), because, as the SETP found out to their surprise, in 1989, minimum speed for 6 horizontal Gs was maximum level speed, so the things could barely even MAKE 6 Gs for a split second in truly horizontal flight...

 

As for the physics, it's amazing that people graduate high school not knowing you can get more force out of something than you put in... Come on guys, this is part of being in a universe with shapes... The Greeks knew better than this 2400 years ago.

 

WoA

 

I went and looked at the actual report and there are few problems with it. Mainly the tests are not conducted at combat or emergency power settings. All power settings were limited to maximum continuous settings. Which for the Mustang is about 1140 hp at the test altitude of 10,000 ft. We can see its about 405 hp less than available than in military settings. Or about 560 less than in War Emergency Power. http://www.wwiiaircraftperformance.org/mustang/P-51D_15342_Level.jpg. The report notes this in the test envelope and limitation section. In all the charts, the power is described as METO, or “Maximum Except for Take Off”. So of course with reduced power settings max G will be closer to maximum speed.

 

This largely invalidates any conclusion you could draw about sustained turn rates based on these tests. As sustained turn rate is a function of specific excess power, Ps. Where Ps =(T-D)V/W. The sustained turn rate line on a doghouse chart is a Ps=0 curve. As the power has been reduced in these tests, the thrust available will be lower and at any given velocity you will have lower sustained turn rate. It has nothing to do with wether the tests are conducted level or diving. It’s a matter of not using enough throttle.

 

The proximity of the maximum speed to the corner speed, or max G available in these test are due to the reduced power settings. Maximum flight speed is defined by the intersection of power required and power available at a given altitude. Since power available in these tests is reduced our top speed is reduced. Since corner velocity is = Square root of 2nmax*W / rho*S*Clmax. It is dependent on speed. Both are functions of power available, in that you can never reach corner velocity without enough power and max speed is a limitation of power available. The relation between Vmax and corner has nothing to do with wether the tests were conducted level or diving, again it’s a matter of how much power was used in the tests.

 

So the sustained turn and acceleration tests in this article are an invalid way to determine flight characteristics. About the only thing of note in this article is the stall testing. I know you’ve talked about the prop as lever, but you’re missing the mark quite a bit. A spinning prop will increase the Cl max of an aircraft. attachment.php?attachmentid=205070&stc=1&d=1551064973

 

While looking at the stall speeds of the mustang in these flight test it looks like the Cl is quite a bit higher than quoted around the web. Based on the stall speed of 87 knots and converting to imperial units the Cl is 2.37 = 8900 / (1.077 * 0.0016249 * 235 *95.5147^2.). However fly the mustang in game at 8900 lbs at 10,000 feet and it stalls right where it does in these flight tests. The effect is built into the sim.

 

Long story short, trust Yo-Yo, he knows what he’s doing and has better sources than most of us.

 

 

you can read the whole article here https://ww2aircraft.net/forum/threads/ending-the-argument.47411/. highlights below.

 

 

attachment.php?attachmentid=205053&stc=1&d=1551051413showthread.php?p=3811365#post3811365attachment.php?attachmentid=205069&d=1551064973

 

 

attachment.php?attachmentid=205067&stc=1&d=1551064974

 

 

attachment.php?attachmentid=205068&stc=1&d=1551064974

169530762_ETA5-min.thumb.jpg.300d4803053efce2ae76cac08d586fdc.jpg

558229722_ETA7-min.thumb.jpg.e6abad8030ca3a86debf57124f17d542.jpg

1983018078_ETA4-min.thumb.jpg.574198f42df0d12c78669167cc1cb648.jpg

1934884191_PropEffect-min.thumb.jpg.64b002de8e1f3db64d224322c15e6bb2.jpg


Edited by Curly
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  • 2 weeks later...
I went and looked at the actual report and there are few problems with it. Mainly the tests are not conducted at combat or emergency power settings. All power settings were limited to maximum continuous settings. Which for the Mustang is about 1140 hp at the test altitude of 10,000 ft. We can see its about 405 hp less than available than in military settings. Or about 560 less than in War Emergency Power. http://www.wwiiaircraftperformance.org/mustang/P-51D_15342_Level.jpg. The report notes this in the test envelope and limitation section. In all the charts, the power is described as METO, or “Maximum Except for Take Off”. So of course with reduced power settings max G will be closer to maximum speed.

 

This largely invalidates any conclusion you could draw about sustained turn rates based on these tests. ]

 

Corner Speed is not sustained 6 G... You only have to touch it...

 

At 240 mph ias you are so far above stall speed there is no reason you cannot touch 6 Gs for a split second, lose 100 mph, and still have plenty of speed above stall, regardless how low your power is...

 

Are you then saying a P-40 needs 320 ias to touch 6 Gs? See how this METO caveat does not work?

 

If the SETP used WEP, the 6G Corner Speed would have been higher, not lower...

 

6G Corner Speed has zero time requirement. But the real nail in the coffin is that amateur guest pilots routinely pull 6 G at 240 ias in the P-51D, no problem, and they certainly don't use power beyond METO... But they do put the nose down, unload the prop, and get 6 Gs easily by pulling up vertically, 80 mph lower than the SETP.

 

Think logically, why P-51s do 6 Gs so easily at 240 ias for guest pilots?... It is 240 in the Flight Manual, with no silly power excuses...

 

The reason the SETP had such a hard time getting 6 Gs is they did not unload the prop by diving...

 

That is why real WWII pilots were so obsessed with lowering the throttle...:

 

http://www.spitfireperformance.com/mustang/combat-reports/339-hanseman-24may44.jpg

 

 

"Dogfight at 500 ft. (with a second higher aircraft, after climbing from 130 ft., having closed to 50 ft. on a landing wheel down 109G)"--"At first he began turning inside me. Then he stopped cutting me off as I cut throttle, dropped 20 degrees of flaps and increased prop pitch. Every time I got close to the edge of the airdrome they opened fire with light AA guns."--"Gradually I worked the Me-109G away from the field and commenced to turn inside of him as I reduced throttle settings."

 

Naturally this was all scorching near 400 mph, so he was so fast he had to kill speed right?

 

 

 

" When the enemy decreased power, I used to throttle back even more. In a high speed the turning radius is wider, using less speed I was able to out-turn him having a shorter turning radius. Then you got the deflection, unless the adversary did not spot me in time and for example banked below me. 250kmh seemed to be the optimal speed (1944 109G). (160 mph)"

- Kyösti Karhila

 

160 mph. There's your preferred 1944 WWII turning speed...

 

 

The very notion increasing power on a prop helps you turn more and at a lower speed is so opposite to what every WWII pilot was faced with, I don't know where to begin...: Please try to look at this with fresh eyes, and understand how the width of the prop, and the resulting leverage, obliterates all the power/drag energy nonsense that works so well with jets:

 

In this new video I go a bit into the absurdity of comparing prop performance with jets:

 

 

WoA


Edited by WrathofAtlantis
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At 240 mph ias you are so far above stall speed there is no reason you cannot touch 6 Gs for a split second, lose 100 mph, and still have plenty of speed above stall, regardless how low your power is...
Stall happens because AoA, not speed, to start with…

 

And, the same a single report, or a single story from a single pilot doesn't make it as the necessary data for a sim like DCS with regard to German pilot stories, it works the other way the same and a single time a single pilot managed to turn better than a probably inexperienced pilot doesn't mean P-51 turned better than the 109 having higher wing load. The fact that you don't quite understand those parameters of corner speed, turn speed, turn radius and everything doesn't make you right about some miraculous physics nobody else knows.

 

I was wondering, do those miraculous physics work in others so called simulators?

 

S!


Edited by Ala13_ManOWar

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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Stall happens because AoA, not speed, to start with…

 

And, the same a single report, or a single story from a single pilot doesn't make it as the necessary data for a sim like DCS with regard to German pilot stories, it works the other way the same and a single time a single pilot managed to turn better than a probably inexperienced pilot doesn't mean P-51 turned better than the 109 having higher wing load. The fact that you don't quite understand those parameters of corner speed, turn speed, turn radius and everything doesn't make you right about some miraculous physics nobody else knows.

 

I was wondering, do those miraculous physics work in others so called simulators?

 

S!

 

i would add that speed has quite big influence in stall

above certain speed AOA will no longer couse stall i call it wing rip off

so above certain speed dependent on the plane stall become imposible :)

System specs: I7 14700KF, Gigabyte Z690 Aorus Elite, 64GB DDR4 3600MHz, Gigabyte RTX 4090,Win 11, 48" OLED LG TV + 42" LG LED monitor

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i would add that speed has quite big influence in stall

above certain speed AOA will no longer couse stall i call it wing rip off

so above certain speed dependent on the plane stall become imposible :)

Well, not really. Stall is always there, it's just you can't pull enough AoA (can't pull enough G's indeed) to reach it, your controls aren't powerful enough (and thanks they aren't). But given something out of the usual happens making you reach the critical AoA you would stall as always no matter what speed you are in. Anyway that's nice to bear in mind as theory for jets (related to turn speed, corner speed, maximum G's available, and so) but in a prop driven aircraft you won't be in such speeds as usual as flying a jet.

 

 

S!

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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Corner Speed is not sustained 6 G... You only have to touch it...

 

At 240 mph ias you are so far above stall speed there is no reason you cannot touch 6 Gs for a split second, lose 100 mph, and still have plenty of speed above stall, regardless how low your power is…

I’m well aware of what corner speed is. I showed how to calculate it.

 

Are you then saying a P-40 needs 320 ias to touch 6 Gs? See how this METO caveat does not work?

No I said, the max speed of this aircraft is close to corner speed because the power settings employed in the test. I don’t know where you’re pulling this 320 number from.

 

We can calculate the corner speed with a 6g load limit based on the formula I gave previously.

Corner velocity @ 6g is = Square root of 2nmax*W / rho*S*Clmax.

Corner velocity @ 6g = 221 Knots=255 mph= Sqrt 6*8900 / (0.0016249 *235 * 2.37)

Which is right near the top level speed for the mustang in these tests.

 

If the SETP used WEP, the 6G Corner Speed would have been higher, not lower…

No corner would have stayed the same, because corner in the SETP tests is limited by the structural limit, in this case 6g. They didn’t want to risk damaging the airframes so all test were limited to a max of 6g.

 

In all aircraft, corner speed is bound by the lift limit, that is the wing’s ability to produce lift, and the structural limit of the airframe. Based on the DCS P-51 manual the load limit is 7g making corner 275 mph or 238 knots. As 238 knots=275mph.= Sqrt 7*8900 / (0.0016249 *235 * 2.37)

 

6G Corner Speed has zero time requirement. But the real nail in the coffin is that amateur guest pilots routinely pull 6 G at 240 ias in the P-51D, no problem, and they certainly don't use power beyond METO... But they do put the nose down, unload the prop, and get 6 Gs easily by pulling up vertically, 80 mph lower than the SETP.

 

Think logically, why P-51s do 6 Gs so easily at 240 ias for guest pilots?... It is 240 in the Flight Manual, with no silly power excuses...

6 g is easy to pull at 240 knots indicated, because 7 g is available at that speed based on the Cl max and wing size. You don’t need any magical prop effect to achieve the performance characteristics your describing. You could hit 6g in a level turn if you’re doing 221 Kias. You just need to have enough thrust to hit these speeds.

 

The reason the SETP had such a hard time getting 6 Gs is they did not unload the prop by diving...

They did conduct the instantaneous turn tests in a dive. “Instantaneous turn performance was evaluated in a wind-up turns from 10,000 ft.” Page 6 of the report. A wind-up turn is a spiraling descent where the speed and throttle are held constant. While bank angle is increased till max load factor is reached. Speed is maintained as load factor increases by pitching the plane down. By limiting the power available they limited speed of the test. This is why max speed is close to max G in these tests. They limited the power available and max g.

 

If you want to prove something about turn rates and prop effects, show a formula and apply it to these tests, otherwise your presenting nothing but opinion.

 

That is why real WWII pilots were so obsessed with lowering the throttle...:

 

http://www.spitfireperformance.com/mustang/combat-reports/339-hanseman-24may44.jpg

 

 

"Dogfight at 500 ft. (with a second higher aircraft, after climbing from 130 ft., having closed to 50 ft. on a landing wheel down 109G)"--"At first he began turning inside me. Then he stopped cutting me off as I cut throttle, dropped 20 degrees of flaps and increased prop pitch. Every time I got close to the edge of the airdrome they opened fire with light AA guns."--"Gradually I worked the Me-109G away from the field and commenced to turn inside of him as I reduced throttle settings."

 

Naturally this was all scorching near 400 mph, so he was so fast he had to kill speed right?

 

 

 

" When the enemy decreased power, I used to throttle back even more. In a high speed the turning radius is wider, using less speed I was able to out-turn him having a shorter turning radius. Then you got the deflection, unless the adversary did not spot me in time and for example banked below me. 250kmh seemed to be the optimal speed (1944 109G). (160 mph)"

- Kyösti Karhila

 

160 mph. There's your preferred 1944 WWII turning speed...

Both pilots are describing 1 circle radius fights. Radius fights are won by having the smallest turn radius and since turn radius = V^2/Radial G, they are won by the craft that can go the slowest and maintain control. This is why the mustang pilot wins when he drops his flaps and cuts the throttle, his turn radius decreases and he ends up inside the 109’s turning circle. The same is true of the 109 pilot, he even describes shrinking the radius.

 

 

The very notion increasing power on a prop helps you turn more and at a lower speed is so opposite to what every WWII pilot was faced with, I don't know where to begin...: Please try to look at this with fresh eyes, and understand how the width of the prop, and the resulting leverage, obliterates all the power/drag energy nonsense that works so well with jets:

 

 

You’re confusing turn rate with radius, and why and when rate wins and when radius wins fights. In two circle fights, rate wins and since turn rate is = G/Air speed. Thrust and Power are very helpful in winning. The opposite is true in one circle radius fights. Where radius = air speed^2/G. Here speed kills, if your going faster, than your radius is bigger and you drift out in front of your opponent. All the pilot accounts you’ve put forth are describing 1 circle radius fights, which is why they want to go slow. This is biasing your theories.

 

 

 

"Turn More" is not an accurate way to describe the motion of the aircraft. Turn more what? More rate? More radius?

 

 

The math I’ve put forth was all developed well before jet engines and is perfectly suitable for evaluating propeller airplanes. I’ve shown how it accurately predicts the performance characteristics of these craft. You however have showing nothing in the way of independent verifiable math proving your claim. Find an equation which shows the effect of prop width and leverage on turn rate or radius.

 

Further more the basis for your claim that this math is unsuitable to predicted turn performance because these test were not conducted in a dive, is also totally wrong, The instantaneous turn test were conducted in a dive and the speed needed to pull 6 g was 240 kias, that's knots indicated which is = to 276.187 mph not the 320 you're claiming. Go back and read the actual report. The physics are accurately predicting the performance of the aircraft.


Edited by Curly
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This what I had access to:

 

 

Corner speeds of all were very close to the maximum level flight speed,

implying very rapid energy loss when turning at the structural limit.

The F6F was in light airframe buffet at 6g at Vmax; the P-47 experienced

light buffet at 4.8g. The FG-1 and P-51 were buffet-free up to 6g.

 

 

 

Heading Change Time (180 deg at METO, 220 KIAS at 10,000 ft.)

FG-1--8.5 sec P-47--9.7 sec F6F--9.9 sec P-51--10.0 sec

 

 

 

I’m well aware of what corner speed is. I showed how to calculate it.

 

 

No I said, the max speed of this aircraft is close to corner speed because the power settings employed in the test. I don’t know where you’re pulling this 320 number from.

 

320 mph ias is the max P-51 level speed meto at 10 000 ft. Easy. What you said is this:

 

"In all the charts, the power is described as METO, or “Maximum Except for Take Off”. So of course with reduced power settings max G will be closer to maximum speed.

This largely invalidates any conclusion you could draw about sustained turn rates based on these tests."

 

So what you said has far wider assumptions than the "reasonable" ones you are claiming...

 

 

 

We can calculate the corner speed with a 6g load limit based on the formula I gave previously.

Corner velocity @ 6g is = Square root of 2nmax*W / rho*S*Clmax.

Corner velocity @ 6g = 221 Knots=255 mph= Sqrt 6*8900 / (0.0016249 *235 * 2.37)

Which is right near the top level speed for the mustang in these tests.

 

 

No corner would have stayed the same, because corner in the SETP tests is limited by the structural limit, in this case 6g. They didn’t want to risk damaging the airframes so all test were limited to a max of 6g.

 

In all aircraft, corner speed is bound by the lift limit, that is the wing’s ability to produce lift, and the structural limit of the airframe. Based on the DCS P-51 manual the load limit is 7g making corner 275 mph or 238 knots. As 238 knots=275mph.= Sqrt 7*8900 / (0.0016249 *235 * 2.37)

 

 

6 g is easy to pull at 240 knots indicated, because 7 g is available at that speed based on the Cl max and wing size. You don’t need any magical prop effect to achieve the performance characteristics your describing. You could hit 6g in a level turn if you’re doing 221 Kias. You just need to have enough thrust to hit these speeds.

 

Note his subterfuge: 255 mph is supposedly "very close" to 320 mph... But then it's actually 276 despite the desperate help of some nose-down... Hmmm... They sure had a hard time lowering that value without unloading the prop, did they? Thanks for strengthening my case... :)

 

This the wording I had available:

 

Corner speeds of all were very close to the maximum level flight speed.(10k)

 

And that to me is close to 300 mph ias, if truly level...

 

They did conduct the instantaneous turn tests in a dive. “Instantaneous turn performance was evaluated in a wind-up turns from 10,000 ft.” Page 6 of the report. A wind-up turn is a spiraling descent where the speed and throttle are held constant. While bank angle is increased till max load factor is reached. Speed is maintained as load factor increases by pitching the plane down. By limiting the power available they limited speed of the test. This is why max speed is close to max G in these tests. They limited the power available and max g.

 

If you want to prove something about turn rates and prop effects, show a formula and apply it to these tests, otherwise your presenting nothing but opinion.

 

So they had trouble matching the claimed values even with the fuzzy factor of putting the nose down?

 

Has a WWII fighter's wing bending measurements ever been taken during level turns? No. I checked: No such data...

 

I posit the wing loads are greater horizontally because the prop must be tilted into slower air, and you ask for formulas about non existent data... Do you see the problem?

 

 

Both pilots are describing 1 circle radius fights. Radius fights are won by having the smallest turn radius and since turn radius = V^2/Radial G, they are won by the craft that can go the slowest and maintain control. This is why the mustang pilot wins when he drops his flaps and cuts the throttle, his turn radius decreases and he ends up inside the 109’s turning circle. The same is true of the 109 pilot, he even describes shrinking the radius.

 

A one circle radius... A one circle radius. Oh my Holy Lord... Just examine what he is referring to:

 

"Dogfight at 500 ft. (attacking a second higher aircraft, after climbing from 130 ft., after having closed to 50 ft. on a landing wheel down 109G at 130 ft.)"--"At first he began turning inside me. Then he stopped cutting me off as I cut throttle, dropped 20 degrees of flaps and increased prop pitch. Every time (Every TIME, got it?) I got close to the edge of the airdrome they opened fire with light AA guns."--"Gradually I worked the Me-109G away from the field and commenced to turn inside of him as I reduced throttle settings."

 

http://www.spitfireperformance.com/m...an-24may44.jpg

 

Let's just say we don't have the same understanding of the English language... The Hanseman fight, btw, is one of the two "initiating sparks" of this theory, although the "triple trick" appears quite often in the 8th AF (about a dozen times, always full coarse prop pitch while slow speed turning).

 

How do the formulas do with the prop on full coarse at minimum speed on the deck?:huh:

 

That couldn't possibly have something to do with stalling the blades... Because he could sense that this unloaded his wings, now could it?:music_whistling:

 

 

 

The math I’ve put forth was all developed well before jet engines and is perfectly suitable for evaluating propeller airplanes.

 

The patent absurdity of this, in the absence of prop-loaded wing bending data, is the very nature of this problem.

 

 

I’ve shown how it accurately predicts the performance characteristics of these craft.

 

You however have showing nothing in the way of independent verifiable math proving your claim. Find an equation which shows the effect of prop width and leverage on turn rate or radius.

 

And why isn't there one? Why is a four square foot thrust pushing assumed to be identical to a 113 square foot surface pulling?

 

Further more the basis for your claim that this math is unsuitable to predicted turn performance because these test were not conducted in a dive, is also totally wrong, The instantaneous turn test were conducted in a dive and the speed needed to pull 6 g was 240 kias, that's knots indicated which is = to 276.187 mph not the 320 you're claiming. Go back and read the actual report. The physics are accurately predicting the performance of the aircraft.

 

If you call "closely" 255 mph being "very close" to 276 mph partially nose-down... I find this problematic, especially if they put the nose down, which greatly strengthens my case...

 

I don't find it close. And no formula can change the fact that the wing bending data for these types does not exist... Formulas are only like a salt grinder: It depends what you run through them, and in this case grinding is not even the correct problem...

 

WoA


Edited by WrathofAtlantis
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This what I had access to:

 

 

 

320 mph ias is the max P-51 level speed meto at 10 000 ft. Easy. What you said is this:

 

 

So what you said has far wider assumptions than the "reasonable" ones you are claiming...

 

Note his subterfuge: 255 mph is supposedly "very close" to 320 mph... But then it's actually 276 despite the desperate help of some nose-down... Hmmm... They sure had a hard time lowering that value without unloading the prop, did they? Thanks for strengthening my case... :)

 

 

You still haven't read the whole report, The maximum level flight speed for the P-51 with meto settings in these tests was 240 Kias. The engine was run at unspecified manifold pressure below maximum settings using low octane fuel. Vmax in these test indicates the maximum speeds achieved in the tests. Not the absolute maximum speed. This is why I have said corner velocity in these tests is close to the maximum speeds in these tests.

 

 

 

eta-6-jpg.469533

 

 

The fact that you don't understand what I'm saying or have not taken the time to read the actual report doesn't make what I'm saying subterfuge.

 

 

You also still don't understand what corner velocity is. 320 is not corner speed. If you pull max g at 320 mph you'll pull 9.4 g's. Since the craft is only rated for 7g you risk breaking it in a 9g turn. Again corner is defined by the where the structural limit meets the lift limit. It is the lowest speed maximum rated g is available. If the structural limit was 9.4 g than corner would be 320 mph or 278 kias. However, it's not, the structural limit is 7g, the corner velocity is 238 kias. You can easily pull 6g at 240 kias and not depart the aircraft or break it.

 

 

 

There are also plenty of tests that deal with wing bending of ww2 craft. The spitfire specifically, dealing with aileron reversal issues.

 

 

 

You also still don't understand what a one and two circle flow is. You can have multiple passes in both. The term denotes whether the flight path of both aircraft make 1 or 2 circles. Not if they pass each once or twice.

 

 

 

I'm happy to discuss this further with you, but at least read the entire report. I it linked in my first post. You should also open another thread to do so and quit cluttering this one up.


Edited by Curly
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Rgarding the OP, which I have only just read for the first time.

 

Is it supposed to be NEWS to us that the FW190, when it first entered sefvice, was superior to the Mark 5 Spitfire?

I thought everyone knew that the FW190 was a "superior" aircraft when it suddenly appeared on the scene in the western theatre. The FW190 came as a massive shock to the RAF. This is why the Mark IX spitfire was worked up, and when it came out, it restored the balance.

 

The very quotes from Johnnie Johnson, in the OP, are reproduced in "Wing Leader", the very book where Johnson uses this event to anecdotalise the overall change in the aerial situation when the Focke-Wulf arrived on the scene, and subsequenlty what a difference the Mark 9 spitfire made when it arrived.

 

Nothing here is "new" nor does it re-write aerodynamic theory. Older lower powered spitfires were suprised by the 190-A. Newer, higher powered spitfires wrested the balance back again.

On YouTube: https://www.youtube.com/philstylenz

Storm of War WW2 server website: https://stormofwar.net/

 

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I just uploaded this new video, with Radial to Inline (La-5and Ki-100) quotes, and the reverse, with very interesting A-8 to Dora nine observations:

 

 

Plus a fascinating melee of 16 P-47 needletip Razorbacks out-turning 20 Me-109Gs, on the deck, while each Jug hauled two one thousand pound bombs(!)...

 

WoA

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Ahhh, an aerodynamics FM thread questioning the veracity of DCS flight models based on nothing more than WWII pilot accounts and reports, by a person who doesn't even have the most rudimentary knowledge of the physics involved, most of which actually conforms to the modeling in DCS when the context is taken into consideration (as philstyle points out).

 

How refreshingly novel. ;)

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I mention in it a quote that actually touches directly on the theory:

 

Donald Caldwell wrote of the FW 190 D-9’s operational debut in his "The JG 26 War Diary Volume Two 1943-1945" (pages 388 – 399): "The pilot’s opinions of the “long-nosed Dora”, or Dora-9, as it was variously nicknamed, were mixed. The new airplane lacked the high turn rate and incredible rate of roll of its close-coupled radial-engined predecessor."

 

I'd be interested to see what "experts" have to say about the term "close-coupled"...

 

WoA

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  • 2 weeks later...
Ahhh, an aerodynamics FM thread questioning the veracity of DCS flight models based on nothing more than WWII pilot accounts and reports, by a person who doesn't even have the most rudimentary knowledge of the physics involved, most of which actually conforms to the modeling in DCS when the context is taken into consideration (as philstyle points out).

 

How refreshingly novel. ;)

 

that a 100 plus sq foot surface is assumed to be as easy to tllt as a 4 sq foot surface illustrates quite well the sheer stupidity of the current "science"...

 

My last quote, in this video

(with another simiar quote about the Dora 9), drew no answer...;

 

Donald Caldwell wrote of the FW 190 D-9’s operational debut in his "The JG 26 War Diary Volume Two 1943-1945" (pages 388 – 399): "The pilot’s opinions of the “long-nosed Dora”, or Dora-9, as it was variously nicknamed, were mixed. The new airplane lacked the high turn rate and incredible rate of roll of its close-coupled radial-engined predecessor."

 

Pilots are of course clueless in front of the great Science...;)

 

WoA


Edited by WrathofAtlantis
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