Dora stall speed

If he dismissed what you brought forward, that would be addressing your report. Because you dont like his answer doesnt mean you are right.

 

Wonder in the code where you would enter "much superior" to make the FM like you think it should be as well...

 

How much is much? Is your much the same as another persons much?

That's why we bring forward actual documentation like windtunnel test reports, to disclose what the actual differences were/are.

Where are the actual wind tunnel reports? I didnt see any full reports included here.

Plenty of reports in this thread, esp. after you merged it. Not sure why you are placing emphasis on "full reports"?

Take for example NACA report no. 824 where much of the information on the NACA 23xxx airfoil is from, it's easily located if you want to read the entire thing:

http://naca.central.cranfield.ac.uk/reports/1945/naca-report-824.pdf

Same goes for NACA report no. 829 if you want the results for all the aircraft under the same test programme:

http://naca.central.cranfield.ac.uk/reports/1945/naca-report-829.pdf

ED works off full reports on the individual aircraft, these our more like summaries and comparisons, and not even off the full aircraft in many respects. ED's document research went well beyond what can be found in google.

You don't seem to know that such reports are public domain, i.e. you're making it sound as if just because it can be found via a search engine then that disqualifies it, which would be a huge mistake and I certainly hope that's not the stance of ED.

I am saying ED has found all these reports, and WELL beyond what can be found on the internet. Limiting yourself to what can be easily found via the internet is the huge mistake, I had a lot of fun hunting for and scanning a lot of microfilm, there is a lot more available than you seem to be aware of, so dont assume everything is available via Google.

I am not assuming it is, what I am saying is that crucial source material is actually available on the net, things that cannot simply be dismissed on the grounds that it was "too easy to locate".

I'll try to find some info on 190g and do a sustained turn test of my own

Sorry for offtopic.

Getting deja vu saying that....

Great, if you find some data on the 190G, and do some tests, make sure to open a thread in chat chat as DCS doesnt have a G module.

:D I do not miss being a moderator, Thanks to you all the other moderators for putting up with all of us. How does the saying go?

You can lead the horse to the water...

Great, if you find some data on the 190G, and do some tests, make sure to open a thread in chat chat as DCS doesnt have a G module.

+1 , indeed, in DCS there is no 190G version... :thumbup:

I have chronic health problems and really strugled to do this tests but i neded to take my mind off more serious things.

My dcs version is older (1.5.6.5199) because like i said i have bigger problems.+no internet connection since a while now( just my phone has connection) .

Still i was curious to find out what's what.

I used :

P51-- 67% fuel to get wing loading of 198.076

190-- 6% fuel , mw50 tank empty , 0% ammo to get a wing loading of 197.97

Low alt ( 300m speed 500 km/h at start) sustained turn at default throttle , no flaps for both planes, default trim settings.

The result was p51 turned better even if wing loading was the same.

In my humble opinion it should be the other way around because of the p51 laminar flow wing.

I will post track files if asked but it's an older version so i'm expecting for someone to maybe prove or disprove my finding by flying this weight settings.

+1 , indeed, in DCS there is no 190G version... :thumbup:

Yes no g version but what if the g version is heavier and has less horsepower and is less aerodynamically refined as the d9 ?

With risk i overdone now my aerodynamic Knowledge, but otto when you look the discussion before it's not so easy..

Not only about the Wingloading, also about how much lift can a Wing produce at certain Speeds without stalling, and this simple a myth the P-51 have bad low speed handling yoyo pointed this out many times...

And this was starting Point about CLmax Discussion here and the P-51 produce much more Lift at slow Speeds then the P-51.

There was chart from Yoyo some Years ago (still dont know it is still accurate) but Fw-190 is turning better at higher Speeds then P-51.

But this hard to use to without producing to much drag with the high Wingloading and the P-51 can turn slower inside your turn stay in shooting distance...

Hope this helps little bit..

With risk i overdone now my aerodynamic Knowledge, but otto when you look the discussion before it's not so easy..

Not only about the Wingloading, also about how much lift can a Wing produce at certain Speeds without stalling, and this simple a myth the P-51 have bad low speed handling yoyo pointed this out many times...

And this was starting Point about CLmax Discussion here and the P-51 produce much more Lift at slow Speeds then the P-51.

There was chart from Yoyo some Years ago (still dont know it is still accurate) but Fw-190 is turning better at higher Speeds then P-51.

But this hard to use to without producing to much drag with the high Wingloading and the P-51 can turn slower inside your turn stay in shooting distance...

 

 

Hope this helps little bit..

I'm not exactly a guru in aerodynamics myself.

But i found p51 cl-max freeflow value of 1.28 (no flaps)

And for d9 yoyo posted a value of 1.35.

And my opinion is for the same wing loading there'a a really low chance a laminar flow wing can produce more lift than a regular one.

But like i said i'm no expert.

Yes no g version but what if the g version is heavier and has less horsepower and is less aerodynamically refined as the d9 ?

What happens to me and to others has been saying for some time, namely that the data of version G can not be considered valid for version D, so any conclusion based on the documentation of the first can not be considered valid for the second.

:thumbup:

But how is DCS coping with the factors that affect the laminar flow: adverse pressure gradients, surface roughness, heat and acoustic energy. Do we notice these on the P51 or it just flies in perfect conditions all the time?

Flight test vs WT figures presented in TN1044:

Even here the laminar flow airfoil didn't gain a CL advantage until Mach ~0.5, which is ~600 km/h at SL (!) At normal dogfighting speeds of M ~0.25-0.3 the CLmax of the laminar flow wing is noticably lower than the NACA 23xxx wing.

But once more this is just ONE report, thus eventhough it supports a lower CL for both aircraft (esp. the P-51), it shouldn't be used as the sole measuring stick. However once again this supports a higher CLmax for the Fw190, esp. at dogfighting speeds.

You did not answer my previous question about two reports you mentioned.

The report nr. is on the documents posted, so it should be obvious?

And you got out of context only one chart for one series of tests. Did you notice in the 1044 the clusters of test curves for various Mach and Re?

Yes I did, and when it comes to real flight tests they tell the same story, i.e. not until M 0.5 does the laminar flow wing match the conventional types in CLmax.

By the way, do you see REAL CL for F6F from different sources?

It's right up there on the chart, 1.35 for the F6F and 1.06 for the P-51 @ M 0.35.

No sir. I guess you can understand what I asked for

Please specify exactly what table, figure, curve at the certain figure you took from the 824 report and the same for the next report.

 

So, we are waiting the aforementioned materials from you proving your statement that an airplane using NACA 23018/23009 or similar have ~ 1.6 for clean configuration. If no, your arguments about "1.58" are nothing.

NACA report 824, page 66.

Again, no, in general. It is just a range of M and Re domains. If you take a look at the Fig. 8 derived from Fig 6 test results you can clearly see (as well as at Fig 9 and, for sure, from the Fig 6) that laminar airfoil has CL max at least not less than a conventional airfoil.

In Figure 6 there is no 23xxx compared, only the lower CL symmetrical 00xx types of the P-39.

So there's what appears to be your main problem, i.e. you're not picking figures from direct comparisons to ensure similar conditions, instead you're cherry picking figures off different graphs.

If you want to know the actual difference between NACA 66 & 23xxx series you have to look at the graphs where they are both directly compared at the same time, and preferably with flight test figures included, like Fig 4 & Fig 14.

It is your main problem - you select facts for your ideas instead of analizing the laws and dependancies behind the numbers.

No, I am selecting the direct comparisons between the 66 series & 23xxx series airfoils available. At the same time you're selecting figures from different graphs and using airfoils from different aircraft irrelevant to the subject as a base for comparison.

Case in point: The P-39 & P-38 are not using the same airfoil selection as the F6F & Fw190, thus they cannot be used as surrogates. The clear difference is made evident in Fig 12.

In addition there was a difference between how effective the ideal smooth laminar flow wing was in windtunnel tests as compared to the wing on actual service aircraft, as revealed during WT tests of actual service wings in the DVL high speed windtunnel.