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What will air combat on the western front in 1945 look like?

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Btw I should note that the above lift coefficients are for an altitude of ~25,000 ft, or in other words bomber cruising altitude.

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Btw I should note that the above lift coefficients are for an altitude of ~25,000 ft, or in other words bomber cruising altitude.

And the P-38 is loaded with nearly 1600l of fuel

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And the P-38 is loaded with nearly 1600l of fuel

 

We can cut that in half by removing 600 kg from the weight, then we get an effective wing loading of 223.3.

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One would think that tests involving combat maneuvers would be done with the fuel state expected during combat.  In the case of the P-51 there were instructions to drain the center tank before engaging in combat.  I would think that performance tests would be done in that state, not full.

 

Any test that we can take seriously would indeed test in that state.

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One would think that tests involving combat maneuvers would be done with the fuel state expected during combat.  In the case of the P-51 there were instructions to drain the center tank before engaging in combat.  I would think that performance tests would be done in that state, not full.

 

 

Any test that we can take seriously would indeed test in that state.

 

 

P-51D: 4,400 kg / (21.83 sq.m. * 1.07) = 188.3

 

 

There are a couple of tests in the ww2aircraftperformance page with the P-51D using weights of 9760 lbs (4427 Kg) and another one with a weight of 9611 lb (4359 Kg). In the first one they specifiy that this weight was with full ammunition, full oil, both wing tanks full (184 US gallons combined), and 25 gallons in the fuselage tank (with a total capacity of 85 gallons). So in total it would be 209 gallons or ~790 liters, maybe you could get like 300 kg less with taking less fuel for your average loweish range sim mission.

 

The ingame specifications are with their standard weights which are full armed and full fuel if i'm correct.

Edited by -=PHX=-SuperEtendard

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21.5 sec would be quite accurate estimate for P-51D with standard load, but if one takes 30% of fuel which is still about 40min of low level flying with not too conservative power settings and that turn time drops to 20 sec with 67'. With higher power rating it should be improved further.

 

Not to mention a quite significantly better instantneous turn performance than the 109.

 

But to claim that Fw190A8 would be able to match or even beat that turn performance is quite silly. Even Dora in sustained turns will have issues against P51D. 109 G14 and K4 will have around 18 to 19 sec depending on load.

Edited by =LD=Solty

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Not to mention a quite significantly better instantneous turn performance than the 109.

 

Only at speeds where stick forces would be high enough to inhibit the 109 pilot, below any such speed the 109 should have a noticably higher instantaneous turn rate by virtue of its lower effective wing loading.

 

But to claim that Fw190A8 would be able to match or even beat that turn performance is quite silly. Even Dora in sustained turns will have issues against P51D. 109 G14 and K4 will have around 18 to 19 sec depending on load.

According to what? A game?

 

TsaGi tested the A8 at 21 sec for a full 360, and as the NACA lift coefficients show us the Fw190 actually has a lower effective wing loading than the P-51.

 

So IMO it would be silly to assume that the P-51 turned better than the Fw190.

Edited by Panthera

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This is silly... - you cannot possibly know what happens with relative turning ability, because of variable weight of fuel and ammunition. Other variables are: engine's timer - in case of the P40 this makes a major difference if it's fresh (or not), coolant/oil temperatures, possible battle damage affecting power or aerodynamics.

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This is silly... - you cannot possibly know what happens with relative turning ability, because of variable weight of fuel and ammunition. Other variables are: engine's timer - in case of the P40 this makes a major difference if it's fresh (or not), coolant/oil temperatures, possible battle damage affecting power or aerodynamics.

Why would you compare aircraft with battle damage and/or underperforming engines? That makes very little sense.

 

When comparing aircraft std. practice is to assume they are in full working order, factory fresh if you will.

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Why would you compare aircraft with battle damage and/or underperforming engines? That makes very little sense.

 

When comparing aircraft std. practice is to assume they are in full working order, factory fresh if you will.

 

Less than ideal conditions are what one will face in actual combat, virtual or not. A plane is factory fresh only once. I have an impression that some people want a definitive, set in stone rule book "what can out-turn what". This is not possible in practice, nor would be that useful anyway because of variables.

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TsaGi tested the A8 at 21 sec for a full 360, and as the NACA lift coefficients show us the Fw190 actually has a lower effective wing loading than the P-51.

So IMO it would be silly to assume that the P-51 turned better than the Fw190.

Lift coefficient of NACA scale model can be quite different from actual aircraft. Test flight report show that mustang has lower stall speed than FW (94mph vs 110mph). Lower stall speed means better effective wing loading.

 

P51B, 9100 lbs, flap up, gear up, power off stall at 94mph.

http://www.wwiiaircraftperformance.org/mustang/p-51b-6883.html

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Less than ideal conditions are what one will face in actual combat, virtual or not. A plane is factory fresh only once. I have an impression that some people want a definitive, set in stone rule book "what can out-turn what". This is not possible in practice, nor would be that useful anyway because of variables.

Well what you're essentially saying is we can't compare anything because of "variables". To an engineer this is a non sequitur as everything can be compared as long as there is satisfactory amounts of reliable data.

 

The comparisons themselves also serve to reveal the variables, as no comparison is identical across the entire height band.

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Lift coefficient of NACA scale model can be quite different from actual aircraft. Test flight report show that mustang has lower stall speed than FW (94mph vs 110mph). Lower stall speed means better effective wing loading.

 

P51B, 9100 lbs, flap up, gear up, power off stall at 94mph.

http://www.wwiiaircraftperformance.org/mustang/p-51b-6883.html

NACA report TN 1044 concerns the real aircraft, the figures I used being derived from actual flight testing.

 

As for indicated stall speeds these are very prone to fluctuate a lot and produce large errors. Take for example the P-51D POH, here the power off stall speed gear & flaps up is listed as 101 mph at 9,000 lbs.

 

The errors become smaller when looking at landing speeds as the AoA is significantly reduced, but they're still not perfect.

 

Hence in order to get the most accurate data you need to conduct thurough measurements of the actual mach specific lift coefficients via flight testing precisely as is the case with NACA report TN 1044.

Edited by Panthera

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Well what you're essentially saying is we can't compare anything because of "variables". To an engineer this is a non sequitur as everything can be compared as long as there is satisfactory amounts of reliable data.

 

The comparisons themselves also serve to reveal the variables, as no comparison is identical across the entire height band.

No - more like we can only make a rough guide, what to expect in the actual air combat.

The major variable will be a human driver - his tactical ability, a wit, and muscles powering control surfaces of most WW2 era planes.

 

You are discussing aerodynamic differences not bigger than few percent. IMHO there is no need to prove that the plane X could out-turns the plane Y by 0.5s. Any variable, or a tactic, may overcome such difference.

Edited by Ehret

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You are discussing aerodynamic differences not bigger than few percent. IMHO there is no need to prove that the plane X could out-turns the plane Y by 0.5s. Any variable, or a tactic, may overcome such difference.

Well these aerodynamic differences are absolutely essential if you desire an accurate simulation of the featured aircraft, and isn't that what sims are ideally about?

  • Upvote 1

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Well these aerodynamic differences are absolutely essential if you desire an accurate simulation of the featured aircraft, and isn't that what sims are ideally about?

 

The fact that those percentages are there for the really skilled to take advantage of is one of the things that makes it a sim. The fact that those percentages usually don't matter at all because tactical awareness is the #1 factor in air combat makes it an even better sim.

 

Really this game is just.. so.. good. Shame I suck at it!

  • Upvote 2

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Well these aerodynamic differences are absolutely essential if you desire an accurate simulation of the featured aircraft, and isn't that what sims are ideally about?

 

Yes, but to a feasible limit. There is no shortage of documents, obscure publications and historic remarks. Eventually, one has to stop digging up stuff to arrive at a conclusion.

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Well, Ive seen this kind of discussions for about 10 years. It seems every year this kind of discussion erupts and we try to reinvent the wheel.

 

 

P-51D: 4,400 kg / (21.83 sq.m. * 1.07) = 188.3 

I have two questions to you as an educated person: 

First, what about graphs in Figure 8 and 9, derived from tests in Figure 6 in the NACA TN 1044 ?

Second, could you be so kind and calculate IAS stall speed for the chosen by you Cl of 1.07 ? 

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Well, Ive seen this kind of discussions for about 10 years. It seems every year this kind of discussion erupts and we try to reinvent the wheel.

I have two questions to you as an educated person:

First, what about graphs in Figure 8 and 9, derived from tests in Figure 6 in the NACA TN 1044 ?

Second, could you be so kind and calculate IAS stall speed for the chosen by you Cl of 1.07 ?

What about those graphs? They include low altitude measurements for the P39 and P51.

 

 

As for calculating the IAS stall speed, can't do for rather obvious reasons (read speed gauge errors) . But I can easily "calculate" the TAS stall speed @ 1.07 clmax, and so can you - hint: mach specific clmax

 

That said Im on my phone and about to be on my way back from work, so an in depth explanation will have to wait till later ;)

Edited by Panthera

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looks like the Battle has already started  :biggrin:  4 pages of what ifs, what I know and what you don't know  :o: 

 

God !  I cant wait for the release and all the post that will follow, should keep me entertained for months :rolleyes:  

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Ok just a quickie to note about NACA TN 1044 before bedtime:

 

We are on the subject of turning flight and thus the lift achieved before an accelerated stall (stalls that take place at a load factor greater than 1), and for this we need real life, full scale Clmax measurements plotted for each specific mach number (speed), and this is what TN 1044 provides.  With these we can deduce the effective wing loading / instantaneous turning ability of the airframe at specific speeds & altitudes.


looks like the Battle has already started  :biggrin:  4 pages of what ifs, what I know and what you don't know  :o:

 

God !  I cant wait for the release and all the post that will follow, should keep me entertained for months :rolleyes:  

 

Battle? I certainly hope not!  I'd much rather it be a quest for answers  to important questions where we all  put our heads together so as to arrive at the most accurate conclusion :)

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Battle? I certainly hope not!  I'd much rather it be a quest for answers  to important questions where we all  put our heads together so as to arrive at the most accurate conclusion :)

 

You are much more likely to get that if you save this sort of stuff for the FM section under the appropriate thread title. Something like "FM relevant data for Bodenplatte plane-set - discuss"

  • Upvote 2

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You are much more likely to get that if you save this sort of stuff for the FM section under the appropriate thread title. Something like "FM relevant data for Bodenplatte plane-set - discuss"

 

Obviously, but the nature of discussion boards means you don't always decide where the discussion begin :)

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Obviously, but the nature of discussion boards means you don't always decide where the discussion begin :)

 

But you can decide where to take it. You also don't always decide where the discussion will end: since the moderators may or may not decide that heading into FM land in this section is breaking forum rules, whereas in the FM section it is quite OK, plus you are more likely to get comment from the sort of people who like to read NACA reports, rather than those who decide how new games should behave based on the memories of old games. ;)

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