P51 wing loading

[RTHolmes]

And the Typhoon?

I cant find any data for Typhoon or Tempest turn performance

[bongaroo]

I've got the answer I'd get right here. 

Pyro does all the modeling.  He says there has been no changes to the P-51's flight envelope.   

I was mostly asking BnZ if he had aired his concerns directly with HTC.  But thanks for the response, always good to see answers from the company.

[hitech]

I'm not an aerospace engineer.  All I can do is look at the "truth" before - and it must have been the 'truth' because any naysayers were shouted down with cries of absolute fidelity BEFORE version 2.07, and compare it with the 'truth' after.  As even a simple mathematician like myself can see, the two are not the same.  This would leave one to believe that somehow, in some way, the 'truth' is wrong, or was.  Since that is obviously impossible given the absolute fidelity of the modelling, and wonder what must have changed with me or my computer. 

Sarcasm aside - all I can do is look at the performance of the planes before and after, and ask WHY there were such drastic changes in performance (I seem to recall Widewing comparing the turning circle of the 190s before and after - and the after circle was 20% larger).  To me, drastic changes in the flight model with no explanation of why is ... unacceptable. 

Because the "NEA SAYERS" are normally like you , and want to state things that are not based in fact. Even if we explained things you would still not be capable of understanding. You also love to throw around words like "Drastic changes in the flight model" when in reality they are very minor changes. The why was stated you just will never be able to , or wish to, understand the answer. You are much more content to sit back and just throw darts, then ever set on a quest for understanding and knowledge.

HiTech

[BnZs]

I cant find any data for Typhoon or Tempest turn performance

Mea Culpa. I meant Tempest. According to DokGonzo's, the Tempest clearly out-turns the P-51 in AHII in both flaps and non-flaps configuration.

[BnZs]

Because the "NEA SAYERS" are normally like you , and want to state things that are not based in fact. Even if we explained things you would still not be capable of understanding. You also love to throw around words like "Drastic changes in the flight model" when in reality they are very minor changes. The why was stated you just will never be able to , or wish to, understand the answer. You are much more content to sit back and just throw darts, then ever set on a quest for understanding and knowledge.

HiTech

Dale, buddy, you know I think AHII is the best and most cleverly designed WWII flight sim out there, and you'd deserve to get paid handsomely for creating for the rest of your life, even if you never did another lick of work on it. But, seriously, how did we end up with Allied and Axis pilots thinking the Mustang is a good-turning planed compared to just about everything but the Spitfire, better than the P-47 and fit to compete with the 109G in the turn? How is it that no one ever noticed the "truth" and said, "WTF, this bucket of bolts can't even turn quite as well as my old razorback Jug, it just can't win turning with a 109 at any practical speed!"? I mean, they noticed that the Wildcats and P-40s couldn't compete with the Zeros turn-for-turn rather quickly...

[hitech]

How is it that no one ever noticed the "truth" and said, "WTF, this bucket of bolts can't even turn quite as well as my old razorback Jug

And hence why you do not understand the concept of flight modeling. In your statement you assume it is because the model is incorrect, instead of assuming the model is correct,and then try finding the real reason people did not speak about it.

When you start being able to answer both questions and look at both sides. I.E. maybe the model is wrong, or maybe what they say in the book is do to some other reason, or because it was not important to them at that time. Then you will start to see data, and flight modeling in a different light.

BnZ to give you an idea of how far you must come, your post before is completely meaningless.

Mea Culpa. I meant Tempest. According to DokGonzo's, the Tempest clearly out-turns the P-51 in AHII in both flaps and non-flaps configuration.

There is no information that can really be discerned from your statement. For one reason the  statement "out-turns" can mean almost anything, and hence can not be used for any modeling. 2nd there are other great problems with your statement as far as modeling is concerned. Now if you can answer why I said your statement is meaningless,and list the reasons why, you will then gain a little knowledge what modeling is all about.

HiTech

[BnZs]

Speaking of meaningless, that is a dodge that would do a politician proud. Relax. There is not going to be any mass canceling of subscriptions just because we are having this discussion.

As far as what "turning" means, in this particular case, it means that the Tempest, as well as the Typhoon and P-47 D-11 can turn with a smaller radius than the P-51. It also means that as a practical fact, the planes mentioned can whip a P-51 in-game in an angles fight from an even break between competent pilots, and that such a contest isn't even close in the case of P-51 vs. 109 of any stripe. This last bit seems strange, given the Mustang's historic reputation. It would have surprised Bud Anderson, among other people.

Are you perhaps saying there is an unknown factor which lead to otherwise intelligent people being completely wrong in their evaluation of the relative merits of the P-51 in a turning contest with other aircraft? If so, what is it? I mean, if for instance there was a mass propaganda campaign by North American so effective even the Krauts believed the disinformation, that would be fascinating episode in and of itself.

And hence why you do not understand the concept of flight modeling. In your statement you assume it is because the model is incorrect, instead of assuming the model is correct,and then try finding the real reason people did not speak about it.

When you start being able to answer both questions and look at both sides. I.E. maybe the model is wrong, or maybe what they say in the book is do to some other reason, or because it was not important to them at that time. Then you will start to see data, and flight modeling in a different light.

BnZ to give you an idea of how far you must come, your post before is completely meaningless.

There is no information that can really be discerned from your statement. For one reason the  statement "out-turns" can mean almost anything, and hence can not be used for any modeling. 2nd there are other great problems with your statement as far as modeling is concerned. Now if you can answer why I said your statement is meaningless,and list the reasons why, you will then gain a little knowledge what modeling is all about.

HiTech

[SgtPappy]

HiTech, there are a lot of biased opinions out there and a lot of weird crap in books that I've seen too that makes me really wonder what's going on. You're right about the both sides arguments... one can't come up with a conclusion until one knows about both sides.

However, when we say 'out-turns' it usually means: 'maintains a higher, horizontal turn rate where both aircraft are turning at maximum sustainable AoA while both are turning horizontally at the same time etc etc.' I mean, there are a lot of things that one can say against my statement but some things are just assumed when they are spoken. i.e. If someone says: 'Wow, this is gay' that is not assumed to mean 'This is homosexual' rather: 'this is stupid.' Correct me if I'm wrong; I don't think I am. After all, many NACA and especially RAF tests use this kind of language which appears so vague at first. I.e. 'Turning circle: 36. The Tempest is not quite as good.' is a direct statement off of an RAF Mustang Mk.III tactical test in 1944.

It's a crappy description, but it gives you an idea of what turning is. We wouldn't assume a faster vertical loop rate as a faster turn rate would we? Maybe, but for the most part, no.

At any rate, the statement:'the Tempest clearly out-turns the P-51 in AHII in both flaps and non-flaps configuration.' is a summary of what happens on Gonzo's test page. Those are the best turn radii (I think) according to Gonzo's tests.

[RTHolmes]

Mea Culpa. I meant Tempest. According to DokGonzo's, the Tempest clearly out-turns the P-51 in AHII in both flaps and non-flaps configuration.

yes it does, my point was that to contest this you need some RL test data on turn radii under the same conditions as the AH tests, rather than just believing it to be the case. reputations often conflict with the real data due to proaganda and a bunch of other factors. example: ask the average Brit which aircraft won the BoB and they will say Spitfire, despite the Hurri claiming most of the kills.

edit: Pappy, this is the problem with using descriptions rather than standardised test data - "turning" could mean instantanious or sustained, with vertical elements or not, and might also include rollrate, onset of stall and control response as these will factor in any ACM which involves "turning". When pilots talk about "agility" or "manouverability" you can also throw in a load of other factors like acceleration, e-bleed, rudder response etc.

[hitech]

SgtPappy I really was not being purposely stupid.

SgtPappy: You prove my point very well, you defined it as Max sustained level turn rate (but you did not define at what alt). But look at the post above, Bnz defined it as smallest turn radius. Those 2 definitions are not the same. So now what did Doc really test. Even in your statement you switch from "maintains a higher, horizontal turn rate" to 'Turning circle: 36. The Tempest is not quite as good.' so even you are speaking of 2 different numbers.

2nd in Bnz's statement he did not define what version of the P51 and variant of the tempest.  So from his statement all I can really conclude is that some version of a p51 turns faster in some manner at some altitude than some version of a Tempest.

I.E. it is totally useless information. And since the poster does not even understand how useless a statement like this is I can not even begin to do any type of evaluation on it.

You may believe that I am nit picking, but I really am not , We come across these type of statements all the time. The uniformed will read something like his statement in a book, and believe it means one thing, while it really was referring to something else. When we read these type of statements and believe that the statement is really based in fact, we then do not automatically think that our model is wrong but begin to evaluate if something is wrong or if both can be correct and there is some thing that is being said , or a slightly different plane configuration that makes both the statement and our model correct.


The processes of modeling is an engineering process. Any one data point can not be looked at in isolation. Anecdotal evidence can be used to swag numbers when nothing better exists, but many things must be considered about that type of evidence.


HiTech

[Urchin]

Because the "NEA SAYERS" are normally like you , and want to state things that are not based in fact. Even if we explained things you would still not be capable of understanding. You also love to throw around words like "Drastic changes in the flight model" when in reality they are very minor changes. The why was stated you just will never be able to , or wish to, understand the answer. You are much more content to sit back and just throw darts, then ever set on a quest for understanding and knowledge.

HiTech

HT,

Try me.  I'd LOVE to know exactly what changed so that the P-51 (actually, the 190 for me) had its flaps down turning performance changed.  Widewing compared the old 190a5 to the new one, the flaps down turning circle is much larger. 

[BnZs]

2nd in Bnz's statement he did not define what version of the P51 and variant of the tempest.  So from his statement all I can really conclude is that some version of a p51 turns faster in some manner at some altitude than some version of a Tempest.

I.E. it is totally useless information. And since the poster does not even understand how useless a statement like this is I can not even begin to do any type of evaluation on it.

I'm sorry, I rather assumed you had seen the image comparing the turning circle of the Mustang Mk.III to the Tempest II&V.

You seem to be getting rather defensive here. That is not my intent. I realize that is enormously difficult to model real worlds physics for computer simulation, and as I have stated before, I think HTC has done the best work to date on WWII flight sims. Nor do I expect some sort of "quick fix" for what may indeed be a very knotty problem.

If there is some logical reason for the disparity between the perceived turning abilities of the P-51 relative other aircraft during the period vs. its performance in game not related to flight model, I would be glad to hear it. Asking questions about this issue does not constitute throwing darts, and pretending this disparity I speak of does not exist is not helpful.

[RTHolmes]

that image, although interesting as a period artifact, is not very helpful for your cause. provide some proper standardised test data on the relative "turn performance" of the pony and jug, temp, whatever and you might have more luck...

[Widewing]

One of the problems associated with modeling an aircraft, specifically a WWII fighter, is that there exists no real world quantitative testing that measured turning ability with flaps fully down. I have never seen any and I'll wager no one else has either. It was something that was not tested. Therefore, HTC has to make decisions based upon what they do know. No doubt, it's an imperfect art.

Likewise, I have not any testing of minimal turn radius clean. Most testing was done on a comparison basis.

There is flight testing of a P-51 (Allison) comparing maneuverability to the P-39D, P-40F (Merlin powered), P-38F and P-47C. We know the takeoff weight of the this P-51, 8,443 lb. We don't know how much of its 140 gallons was burned off prior to the actual "dog fights", but we can assume that it was proportional to the others. Note that this P-51 shares the same basic air frame with P-51B, including the wing and tail appendages, except that the rudder trim was changed and rigged as an anti-balance tab. This Allison P-51 is lighter by 440 lb in basic weight.

The text from the test describes the comparison as follows:

b. Maneuverability.    The subject aircraft was flown in "mock" combat against the P-38F, P-39D, P-40F, P-47B, and the Mitsubishi "00" type of aircraft.

 c. The following results were obtained:

(1) The subject aircraft was found to be superior in speed of the Mitsubishi "00", P-39D, P-47F at all altitudes and the P-47B and P-38F up to fifteen-thousand (15,000) feet.
 
(2) The subject aircraft was found to be superior in rate of climb to the P-39D, P-40F, and the P-47B up to fifteen-thousand (15,000) feet.
 
(3) The acceleration in dives and the maximum permissible diving speed of the subject aircraft is superior to all types tested.
 
(4) The turning characteristics of the subject aircraft are substantially the same as the P-40F and the P-39D. None of these appears to have any definite superior turning characteristics.
 
(5) In close "dog fighting" the subject aircraft has the very decided advantage of being able to engage or break off combat at will. However, if neither airplane attempts to leave the combat, the P-40F is considered to have a slight advantage.

Let's look at our P-51B... The minimum takeoff weight that can be produced in the game is 8,213 lb. This is obtained by shooting out all of the ammunition prior to takeoff. This weight is substantially less than the takeoff weight of the P51 in the above test. Even if the that P-51 had burned off 40 gallons of its fuel, it would weigh in at 8,195 lb, very close to the 8,213 lb for a light P-51B.

Let's compare our P-40E to the P-40F. Like the P-51B, this P-40 was fitted with a Merlin. This installation added nearly 400 lb to the airframe. So, if we compare the P-51B to the P-40E, we need to allow for an additional 400 lb of weight for the P-40E. Takeoff weight for a fully loaded P-40F is 8,678 lb. Let's reduce that by 40 gallons of gas. That comes out to 8,430 lb. With that figure in mind, I'll configure the P-40E to that weight. To get this, I load 75% internal fuel and a drop tank. I then have to shoot out a little ammo to get down to 8,430 lb. The drop tank adds drag, so the numbers will be skewed to reflect that.

With both fighters configured, I then do a minimum turn radius test, both clean and with full flaps.

So, in "close dog fighting", is the P-51B only "slightly" inferior to the P-40E at the weights defined above?

Minimum turn radius clean...

P-40E: 743.5 feet
P-51B: 770.6 feet

Minimum turn radius full flaps...

P-40E: 566.4 feet
P-51B: 601.1 feet

Remember now, the P-40E has 75% fuel and a 75 gallon drop tank, vs a P-51B with 25% fuel and no ammo.

The ratio between clean and full flaps is about the same between them.

However, I don't see this as a "slight" difference. It's roughly the same as the difference between a SpitV and a SpitIX, which is much more than "slight".

Moreover, the fact that a clean A-20G easily out-turns a clean P-51B should create a pause for thought, agree?


My regards,

Widewing


 

[bozon]

...
However, I don't see this as a "slight" difference. It's roughly the same as the difference between a SpitV and a SpitIX, which is much more than "slight".

Moreover, the fact that a clean A-20G easily out-turns a clean P-51B should create a pause for thought, agree?
...

Going by memory here, I recall spit IX and spit V to be considered "equal" in turn ability in evaluation tests.

Many big aircraft (empty) will have lower stall speeds that a P51. Most likely, the will have smaller minimum turn radius. It does not mean that they will win a dogfight vs. a P51, as I am sure you know.

Testing "turn ability" is futile as a mean to test a flight model. If you like, you can test the actual drag and lift of the plane at various configurations and speeds and then see the effects of flaps and other things. I have not devised a full testing procedure yet, and definitly do not have the time to do it, but in principle this can be done either by power off glide at constant speed and reading the rate of decent and weight, or turning on auto level and monitoring the minimum speed before loss of alt (this will have to assume something about what auto-level actually does). Some of the aeroengineers here probably have some standard way to do it.