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Another look at turn times

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He's right, these are exactly the problems and I know they were addressed in a simplified way in previous flight sims, for instance with drag = function of AoA = A + B*AoA + C*AoA². Works well enough for the most part. I don't know how detailed things are dealt with in BoX, but what I take away from some developers statements - it's much more detailed, much more complex and if tuned right can be much more accurate.

 

Your above observations are absolutely spot on.

 

WRT to your question about propeller efficiency - it's easy to find a ballpark, but it may vary considerably depending on state of flight and type of propeller. If you for instance look at this, you'll find comparative propeller tests with a P-47B, fourth test from the top. Top speeds at 25k varied between 397 and 419mph, climb rates at 20k between 2180 and 2460fpm. That's 5% in speed and 10% in climb - huge margins, all down to different prop efficiencies. And to make things worse, the worst climber was the fastest in level flight...propeller characteristics are as type dependent as aircraft characteristics.

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I just realized I made a big mistake concerning the Yak S69: I took the old Il-2 value of 21.2 s turn time instead of the new updated value of 19.2 s.

 

Again, not claiming my numbers are a 100% but applying the same laws of physics and assuming that Russian and German designers were about as good in transforming engine power into thrust and angle of attack into lift then the relative values should be close enough.

 

My sea level estimates             New Il-2 numbers                       Difference %

   

Fw-109A3: ca 21.8 s                 24.7s                                            +13.3%

Me-109F4: ca 18.6s                 20.3                                              +9.1%

Me-109G2: ca 19.0s                 22.2                                             +16.8%

Yak-1 s69: ca 19.0 s                  19.2                                             +1.1%

 

I also updated the above numbers since my first estimate was for 1 Km altitude and the above table is now updated with sea level estimates.

 

So it turns out I was mistaken and I have to take back what I said earlier about the numbers in IL-2 not being too bad: It does look bad now since it’s no longer a case of ALL IL-2 turn time numbers being shifted to a higher value. It’s only the A3, F4 and G2 that are shifted to a higher value with the Yak estimate being essentially the same. The F4 at 10 % more is bad enough but the A3 and G2 being about 15% worse is a huge difference.

 

I guess the reason for this is simply that the developers revised both Yak’s turn rate numbers when they introduced the S127 to be more in line with the historical values. Hopefully the planned updates for the Me-109 (rudder/roll coupling) and the Fw-190 A3 FM when A5 is introduced also includes a turn rate tuning of these planes as seems to have been done on the Yak.

 

Would be nice with some info from the developers on this though.

Edited by Holtzauge
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I've taken the data provided by the devs in DD123 and put it in a table for a plausibility check. I've been calculating the efficiency. Basically, I calculated the induced drag on one side and the available thrust on the other. The ratio of drag/thrust is my efficiency.

 

Problem is the foundation is flawed JtD.  Induced drag is based upon Coefficient of Lift and your assumptions for the efficiency factor.  Assume the wrong CLmax, propeller efficiency, and (span, oswald, aircraft, or wing) efficiency results in erroneous results.  You are piling assumption upon assumption all wrapped in a method of your own creation.  It is very likely to be ignored because of that.

 

I would ignore it as it goes down many rabbit holes.

 

Just use convention and do NOT make up your own theories.  You will find that the VVS turn times agree very well with convention if the conditions are properly converted.

 

TSAGi kind of knew what they were doing and were not learning it off the internet or going down rabbit holes.

 

What are you doing regarding oswald's?  There are good fairly simple techniques to estimate it.

 

For example you can return a very reasonable estimate using some measured data from the design such as Taper Ratio, Aspect Ratio, wing span, and mean fuselage diameter.

 

Take the FW-190 because we have very good engineering data on the design:

 

Our inviscid efficiency:

 

 

etheo = 1/(1+F(lambda) * Aspect Ratio) 

 

F(lambda) Value determined by graph using the taper ratio of the design = .00375  (I can give you the graph as well as the entire theoretical mechanics).

 

etheo = 1/(1+.00375 * 5.8)  = 1/ 1.02175 = .97871

 

Now we need to correct the inviscid drag and factor in the viscid drag.

 

Fuselage correction = 1 - 2{(mean diameter of the fuselage/wingspan)}^2 = 1 - 2{(4.36ft/34.5ft)}^2 = .968

 

Mach effects runs thru another formula but the net result at a Mach of .228 as 1.  

 

Our corrected Oswald's efficiency accounting for viscid, inviscid, and mach effects comes out too:

 

e = etheo * Fuselage Correction * Mach effects = .97871 * .968 * 1 = .947

 

So convention tells us that oswald's efficiency for the FW-190 is ~.947 at turning velocity.

 

Now, .85 is a very valid and normal assumption for the entire envelope.  Mach effects will drop that efficiency as the velocity increases and that will be about the average over a subsonic designs envelope.  The point being to be very cautious and use valid and normal assumptions.  Use conventional theory properly as well the mathematical conventions required by it and do not make up your own theory.

 

It seems to me that you are trying to work propeller efficiency backwards.

 

There does not need to be any "theory" of our own making in that goal.  

 

Aircraft performance math dictates that turn performance is the result of power available to power required.  If you want to determine the games propeller efficiency in a turn then you simply use the shaft horsepower of the engine minus the power required to reproduce the games turn performance times.

 

Power required to reproduce game turn times / Shaft Horsepower of the engine = Games Propeller Efficiency

 

That is all you have to do.

.

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Problem is the foundation is flawed JtD.  Induced drag is based upon Coefficient of Lift and your assumptions for the efficiency factor.  Assume the wrong CLmax, propeller efficiency, and (span, oswald, aircraft, or wing) efficiency results in erroneous results.  You are piling assumption upon assumption all wrapped in a method of your own creation.  It is very likely to be ignored because of that.

 

I would ignore it as it goes down many rabbit holes.

 

Just use convention and do NOT make up your own theories.  You will find that the VVS turn times agree very well with convention if the conditions are properly converted.

 

TSAGi kind of knew what they were doing and were not learning it off the internet or going down rabbit holes.

 

What are you doing regarding oswald's?  There are good fairly simple techniques to estimate it.

 

For example you can return a very reasonable estimate using some measured data from the design such as Taper Ratio, Aspect Ratio, wing span, and mean fuselage diameter.

 

Take the FW-190 because we have very good engineering data on the design:

 

Our inviscid efficiency:

 

 

etheo = 1/(1+F(lambda) * Aspect Ratio) 

 

F(lambda) Value determined by graph using the taper ratio of the design = .00375  (I can give you the graph as well as the entire theoretical mechanics).

 

etheo = 1/(1+.00375 * 5.8)  = 1/ 1.02175 = .97871

 

Now we need to correct the inviscid drag and factor in the viscid drag.

 

Fuselage correction = 1 - 2{(mean diameter of the fuselage/wingspan)}^2 = 1 - 2{(4.36ft/34.5ft)}^2 = .968

 

Mach effects runs thru another formula but the net result at a Mach of .228 as 1.  

 

Our corrected Oswald's efficiency accounting for viscid, inviscid, and mach effects comes out too:

 

e = etheo * Fuselage Correction * Mach effects = .97871 * .968 * 1 = .947

 

So convention tells us that oswald's efficiency for the FW-190 is ~.947 at turning velocity.

 

Now, .85 is a very valid and normal assumption for the entire envelope.  Mach effects will drop that efficiency as the velocity increases and that will be about the average over a subsonic designs envelope.  The point being to be very cautious and use valid and normal assumptions.  Use conventional theory properly as well the mathematical conventions required by it and do not make up your own theory.

 

It seems to me that you are trying to work propeller efficiency backwards.

 

There does not need to be any "theory" of our own making in that goal.  

 

Aircraft performance math dictates that turn performance is the result of power available to power required.  If you want to determine the games propeller efficiency in a turn then you simply use the shaft horsepower of the engine minus the power required to reproduce the games turn performance times.

 

Power required to reproduce game turn times / Shaft Horsepower of the engine = Games Propeller Efficiency

 

That is all you have to do.

.

 

Crump: JtD is not making up and new theories and what he writes makes perfect sense. At least to an MSc. in aeronautical engineering like me and if he was off down a rabbit hole I think I would notice. In fact what he wrote seems perfectly lucid as opposed to some of what you write above which I quite don’t follow. So let's just agree to disagree on who is chasing down the rabbit hole OK?

He's right, these are exactly the problems and I know they were addressed in a simplified way in previous flight sims, for instance with drag = function of AoA = A + B*AoA + C*AoA². Works well enough for the most part. I don't know how detailed things are dealt with in BoX, but what I take away from some developers statements - it's much more detailed, much more complex and if tuned right can be much more accurate.

 

Your above observations are absolutely spot on.

 

WRT to your question about propeller efficiency - it's easy to find a ballpark, but it may vary considerably depending on state of flight and type of propeller. If you for instance look at this, you'll find comparative propeller tests with a P-47B, fourth test from the top. Top speeds at 25k varied between 397 and 419mph, climb rates at 20k between 2180 and 2460fpm. That's 5% in speed and 10% in climb - huge margins, all down to different prop efficiencies. And to make things worse, the worst climber was the fastest in level flight...propeller characteristics are as type dependent as aircraft characteristics.

 

But I think the P-47 is a bit of an exception and the improvements that came with the paddle blade props when they upgraded from the "toothpick" blades was a bit of a special case I would say because that was NOT a good match to begin with since the toothpick propeller blade solidity was too low for the power it had to absorb in climb conditions.

 

What I meant earlier on when I said that the Allied and Axis propeller technology was about the same was that usually there was a good match between propeller and engine and that there was not much to choose in terms of efficiency between say a German 3 bladed wooden prop on a late war Fw-109 D9 and a US hollow steel 4 blade prop on a P-51D. At least that seems to be the case because my C++ prop model does not count blades or width but disc loading and propeller solidity and when I reverse engineering performance numbers this usually leads to fairly close propeller efficiency numbers irrespective if the plane I'm estimating was equipped with a 3 or 4 blade prop.

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Crump: JtD is not making up and new theories and what he writes makes perfect sense. At least to an MSc. in aeronautical engineering like me and if he was off down a rabbit hole I think I would notice. In fact what he wrote seems perfectly lucid as opposed to some of what you write above which I quite don’t follow. So let's just agree to disagree on who is chasing down the rabbit hole OK?

 

LOL...

 

What don't you follow it with your MsC in Aeronautical engineering?  

 

Yes, I purposely used the general terms for what I what I was doing but it all follows common theory and the correct principles.

 

Again,  without the details of what JtD is doing it is impossible to say the degree of useful information being produced.  My post was not to discourage him but rather to redirect his course from his own theories of "efficiency"

 

Aircraft performance math dictates that turn performance is the result of power available to power required.  If you want to determine the games propeller efficiency in a turn then you simply use the shaft horsepower of the engine minus the power required to reproduce the games turn performance times.

 

Power required to reproduce game turn times / Shaft Horsepower of the engine = Games Propeller Efficiency

 

That is all you have to do.

 

Now whether that is games value is correct or not depends on the specific off the propeller design AND the theory being used.

 

 

 

At least that seems to be the case because my C++ prop model does not count blades or width but disc loading and propeller solidity and when I reverse engineering performance numbers this usually leads to fairly close propeller efficiency numbers irrespective if the plane I'm estimating was equipped with a 3 or 4 blade prop.

 

Momentum Theory.......Limited usefulness at predicting propeller efficiency is one of the basic limitations of its use....it only shows the upper end of theoretical maximum efficiency for an infinite number of blades.  It is useful though in that it show us there is little to choose from regarding propeller designs and the common assumptions work just fine.

 

Blade element theory is more accurate as is what most propeller designers use to predict the performance but one must know the details of the propeller design being evaluated.  Like anything, wrong information can lead to wrong results such as one case I know of where the individual analyzed the tip of a propeller with a working radius of .7.   If you compare propeller efficiency at a radius of .95 on a propeller with a working radius of .7.....of course it is not going to appear to be a very efficient design, LOL.

 

 

 

At least to an MSc. in aeronautical engineering like me and if he was off down a rabbit hole I think I would notice.

 

Like you did not notice this had nothing to do with anything IL2 but just decided to cheer the guy on instead of helping him out?  LOL

 

https://forum.il2sturmovik.com/topic/26384-re-dev-report-138-vdm-propeller-some-historical-files/

Edited by Crump

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...Again, not claiming my numbers are a 100% but applying the same laws of physics and assuming that Russian and German designers were about as good in transforming engine power into thrust and angle of attack into lift then the relative values should be close enough...

Thanks for the comparative figures from your C++ simulation here. It is interesting that the pecking order is fairly similar to my simple check, just G-2 and A-3 are the other way round. Just to be sure - did you use combat, not emergency power with the G-2?

 

But I think the P-47 is a bit of an exception and the improvements that came with the paddle blade props when they upgraded from the "toothpick" blades was a bit of a special case I would say because that was NOT a good match to begin with since the toothpick propeller blade solidity was too low for the power it had to absorb in climb conditions.

I agree, it is an extreme in that regard. I don't know a worse case from the top of my head, but it helps illustrating the point. I also agree that there's little to chose between properly matched props. One does have to look a little closer in order to find differences, which I didn't want to do.

 

But it doesn't make a difference in my comparison here, it's not relevant if the losses come from a poor prop or a poor airframe - it's all covered in the single efficiency figure.

Edited by JtD

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LOL...

 

What don't you follow it with your MsC in Aeronautical engineering?  

 

Yes, I purposely used the general terms for what I what I was doing but it all follows common theory and the correct principles.

 

Again,  without the details of what JtD is doing it is impossible to say the degree of useful information being produced.  My post was not to discourage him but rather to redirect his course from his own theories of "efficiency"

 

Aircraft performance math dictates that turn performance is the result of power available to power required.  If you want to determine the games propeller efficiency in a turn then you simply use the shaft horsepower of the engine minus the power required to reproduce the games turn performance times.

 

Power required to reproduce game turn times / Shaft Horsepower of the engine = Games Propeller Efficiency

 

That is all you have to do.

 

Now whether that is games value is correct or not depends on the specific off the propeller design AND the theory being used.

 

Momentum Theory.......Limited usefulness at predicting propeller efficiency is one of the basic limitations of its use....it only shows the upper end of theoretical maximum efficiency for an infinite number of blades.  It is useful though in that it show us there is little to choose from regarding propeller designs and the common assumptions work just fine.

 

Blade element theory is more accurate as is what most propeller designers use to predict the performance but one must know the details of the propeller design being evaluated.  Like anything, wrong information can lead to wrong results such as one case I know of where the individual analyzed the tip of a propeller with a working radius of .7.   If you compare propeller efficiency at a radius of .95 on a propeller with a working radius of .7.....of course it is not going to appear to be a very efficient design, LOL.

 

Like you did not notice this had nothing to do with anything IL2 but just decided to cheer the guy on instead of helping him out?  LOL

 

https://forum.il2sturmovik.com/topic/26384-re-dev-report-138-vdm-propeller-some-historical-files/

 

You've violated rules of the forum already 12 times and punishments don't make on you any impact. There is enough.

 

2. This forum is provided by 1C-777 Ltd. as a courtesy and its usage is a privilege and 1C-777 Ltd. reserves the right to ban any member temporarily or permanently for any reason at any time. Any penalties listed below for violations of the rules are guidelines only and forum administration may take additional action if they feel it is warranted. Use of the forum is not connected to usage of the game and access to this forum is not guaranteed to users as a consequence of purchasing the game.

 

А complete ban on access.

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Please keep in mind that the figures are simply taken from the DD, not actual in game figures. The answer to any question raised could be a simple typo, on my part, or the devs part.

 

Several odd things pop up.

2) The B109F-2 is clearly worse than all other Bf109's, also worse than the Bf109E-7, which is odd.

 

I would reckon that this a result of the real (Soviet?) life examples used as reference were compromised, i.e. down on power, hence it could result the odd turn figures for these types.

 

I also wonder wheter this would effect turn times for the 109G-2, since the listed cc. 22 sec is considerably higher than that of the actual one captured at Stalingrad (20 secs), though appearantly the G-2 figures are more closely based on March 1943 E-Stelle Rechlin figures than anything else. This trend of higher turn times also appears with the other 109 series aircraft.

 

Given that the Devs IIRC requested propeller efficency charts for VDM 109 propellers, as the best closest basis available to them was a DVL propellor doc , leading I wonder if the issues noted here and other parts of the board are related to '109 hanging on the prop' doubts.

 

a) possible influence/compclusion derieved from of compromised test aircraft (F-2 and E) results on the whole 109 FM

b) Insufficient data for propeller effiency curves (perhaps too high efficency at low speeds compared to the real one

c) leading to perhaps overstated thrust figures which are compensated by the FM - i.e. there is more thrust used but less CL/Drag present in the model.

 

Just an educated guess though.

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Well I don't, because we were relying on him to get some documents from the smithsonian. Is that a subform ban, or a complete ban overall?

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Well I don't, because we were relying on him to get some documents from the smithsonian. Is that a subform ban, or a complete ban overall?

He promised me months ago he'd get me data for the Fw 190. He never did, and then later accused me of taking credit for the data he never sent.

 

Sorry to burst your bubble but I don't think it was going to happen.

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Whatever it is - it's yet another person banned from our little community.

 

Yay, let's all rejoice...the community just got even smaller.

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Thank you, Black Six.

---

Since this discussion now has a chance for survival, I've updated the first post.

---

@Kurfurst - interesting thoughts, all I know from the developers is that the issue is very complex. I wouldn't be surprised if the props had their share in it, but then I guess it doesn't explain everything.

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It is interesting to note the Junkers triplane has an equivalent efficiency to the I-16 :D

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Thanks for the comparative figures from your C++ simulation here. It is interesting that the pecking order is fairly similar to my simple check, just G-2 and A-3 are the other way round. Just to be sure - did you use combat, not emergency power with the G-2?

 

When you say combat power for the G2 I assume you mean 1.3 ata? If so then yes.

 

Going forward with all this maybe a good way would be to simply ask in the "questions to the developers" thread if they have any plans to overhaul the turn rates? To me it looks like the Yak is now pretty close to the historical values and AFAIK this change came with the introduction of the S127?

 

So maybe there is a similar turn time overhaul planned for the others, i.e. for the Me-109's when they fix the rudder/roll coupling and for the Fw-190 A3 when the A5 is introduced? So before one spends too much more time on collecting data or arguments maybe it would make sense to before that check if they already have plans to tune the others like they have the Yak's?

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I've contacted the devs via PM already. I didn't push for a discussion, because I'd prefer them to spend their time improving FM's, not discussing shortcomings. I'm always under the impression that they have plenty of really useful things to do, and want to get them done.

 

I don't think I'm violating the P in PM if I say that they are aware of issues like that, the reasons are complex and given enough time, they'll improve things. Problem being finding that time...

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Great! So please tell me if I got this wrong or else I'll take that as a confirmation then that they agree with our analysis that some planes like the F2, G2 and A3 have a bit higher turn times than they should and that they have this in the backlog of things to do then? Just want to make sure......... ;) 

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No, not that specific. But imho it would be a likely outcome if they had the time.

 

I've just checked the G-4 in game and got it turning at 21.4s at combat power (1.3/2600). Since this is better than the G-2 and F-4, I'm assuming that something changed and older FM's will need to be updated.

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OK, good to know that the G4 is a step in the right direction and this maybe supports the theory that when newer planes are introduced this is refined. Would have been nice with a G2 overhaul though in the same way as the Yak-1 S69 seems to have been addressed when the S127 was introduced.

 

But while 21.4 s at sea level certainly is a step in the right direction it still sounds a bit high: OTOH I have calculated the G2 assuming a weight 3030 Kg and I assume the in game G4 is a bit heavier?

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Engine charts to determine power at altitude might be useful. Looking at Allison charts for V1710-39, 56" which produces about 1470 HP at sea level translates to about 1530 HP at 1km (well, 3000 ft), assuming it can maintain that manifold pressure flying at fairly low speed. Assuming Russian test was done on 46" Hg (before uprating of engine, allowed for takeoff), it would be 1250 HP at 1km altitude.

 

I would discount Russian test of Bf109E because they seemingly had all sorts of trouble with the plane. I assume it was somehow damaged, really. It's the most plausible explanation.

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I would discount Russian test of Bf109E because they seemingly had all sorts of trouble with the plane. I assume it was somehow damaged, really. It's the most plausible explanation.

 

Both the Russian tested 109E and F-2 seem to have been suffering from massive engine related troubles. The former does not appear to develop power at low altitude, and the latter was in fact so bad at altitude and the obtained results so useless that the Russians had to extrapolate the high altitude figures.

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i often wondered that myself..

How can field test done with captured planes be considered useful for true stats?

i mean i could go steal someone car put it on a dyno and get very different results tho those when it came out of factory.

:|

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Its a hit or miss. The Bf 109G-2 they have captured near Stalingrad is, on the other hand, one of the best performing examples. I wonder if that is because IIRC that they got it in an airfield, so they probably also liberated a couple of German mechanics with the know-how, proper tools, manuals fuels and lubricants etc.

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Why Crump was banned?

 

Let that go.

Edited by Bearcat
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I have cleaned up 3 posts in this thread. Let's keep it moving folks. What is done is done. There wer more than enough warnings. Move along there is nothing to see here.

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The official figures have been updated (Bf110G-2, Fw190A-3), so I've updated my calculation in the first post. I've also added all the aircraft I didn't look at so far.

 

Generally the new FM's again increase the efficiency of the aircraft, the Fw went up 5%, the Bf110G-2 is 6% more efficient than the older Bf110E-2. I hope this trend continues and I hope that older FM's will be updated as time allows. It could mitigate or even solve issues for instance with the P-40E1.

 

Of the new numbers added, the Ju87D-3 was by far the biggest surprise for me. Clearly, aerodynamic efficiency is not what comes to mind when looking at that plane. I haven't confirmed the turn time in game as of yet.

Edited by JtD
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I think this is a great way to "gut check" the FMs 

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Interesting to note, 

 

HP does not equate to thrust

 

Figure that one out ;)

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P = F*v

 

Power equals Force times velocity, and therefore the slower you go at the same power, the more thrust you generate. Which means that while having the same power, the Fw190 produces less thrust than the La-5, because the speed is 280, as opposed to 270.

 

And yes, it's basically a 'gut check' table.

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I've updated the table in the first post as the devs have updated their data. Changes are basically the addition of the He111H-16, Il-2mod43 and Fw190A-5. No surprises there, all of them are close to their already existing relatives.

 

I noticed that both the He111H-6 and H-16 are listed with the Jumo211F, however, on the H-6 it is listed with 1420hp, on the H-16 with 1340hp. 1420hp is the figure for the Jumo211J, which is the F with an intercooler. My manuals say both the H-6 and the H-16 used the F with 1340hp, the J with 1420hp was used on the Ju88A-4.

 

I also noticed that the wing area for both Heinkels is given with 79.5m², however, this is the actual geometric wing area as given by Heinkel. The aerodynamic wing area, which includes the fuselage cross section, and which is stated for all other aircraft as far as I can see, is 86.5m².

 

The issues could be limited to typos/mix ups in the diary text, doesn't necessarily have to translate to the game.

post-627-0-22452800-1494074991_thumb.jpg

Edited by JtD

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Could be worth asking them by PM to clarify about this specific point, or in the question to devs section.

 

For the 1420HP on the H6, this is clearly a typo that Han overlooked. A few months back, it was listed as having 211J engines, but this only got partially corrected. But Han confirmed that the H6 ingame uses the 211F engines.

Edited by F/JG300_Gruber

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Figures for the Spitfire have been provided by Han, unfortunately, the power figures for the turn times are missing. So I can't update the table, which I want to be solely based on dev data.

 

For discussion purposes, 3000rpm/9lb should generate in the region of 1000+hp for the Merlin 45 at sea level, 900+hp for the Merlin 46. The turn time difference is listed as 3s between the 45 and 46, which is huge. I suppose the turning speed of 270 is way too high, in particular for the MErlin 46 version, which has a really low top speed.

With that, overall efficiency is 37% for the Merlin45, 32% for the Merlin46 and thereby very low.

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I just did a quick C++ simulation and I think best turn time should be in the order of 16-17 s at sea level. IIRC then Soviet sources say 17 s at 1 Km? I get the best turn rate at ca 235 km/h SL. Reading off at 270 Km/h that is reduced by around 1 s so not a huge difference. Turn times in the order of 22 s at sea level sound very pessimistic to me.....

 

 

post-23617-0-95260000-1499611157_thumb.gif

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Yeah, it's fishy. Overall the Spitfire FM right now is a good mix of hit and miss. I hope they find the time to make a few adjustments, so that at least all basics are properly modelled.

 

I'm sure I'll test the Spitfire in game in the near future, to confirm (or hopefully not) the turn time figures above.

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I think it is safe to say that the spit is the best turner in game and i dont know how to read the high turntimes in the manual correctly. You can feel how good and fast it turns and i cant believe the manual in this regard.

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Preliminarily I'm at 21s and 19s instead of 25s and 22s as stated, turning at 160-170mph. You can probably chop off another one or two seconds by going from 9lb to 12lb or 16lb, so yes, it's a very good turn fighter.

 

First aircraft tested to behave completely different in game than stated by the developers.

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Maybe it's just a typo?

 

Another thing I plan to take a closer look at is the developer stated climb rate which seems low to me but that is a separate issue so I won't derail this thread by delving on that here. ;)

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Since there are quite a few issues (climb, turn, attitude, roll, buffeting, stability, trim, ...), maybe just start a general Spitfire FM topic? It's the Spitfire, it going to be epic. It took the P-40 near a year to get to 25 pages, I'm sure the Spitfire can do it in a month. :)

 

I'd do it myself, but today I'm not in the mood for a meaningful opening post.

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Well I guess we can wait a few days and just savour flying for the time being: I just love the way it handles and it's currently my favourite ride! :good:

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