Explain this and win the prize!

[Crumpp]

As noted several times the germans lost France summer 1944, therefore it is safe to say that at least Fw data for the Ta 152 is based on tests with scale models and even the data for the Fw 190s seem to be at least partially based on model testing because it it contains detailed drag values for different parts of the airframe and claims about interference drag.

You need to study up more on the Ta-152 program.  Prototypes were flying in 1943 Gripen as were the FW-190A9 prototypes.

Pope is very clear on this, lift curve as well as drag rise due to lift coefficient change can be determined with good accuracy despite changes in the value of the Reynolds number. Besides we don't need to be very accurate here; wind tunnel data as well as flight tests indicate that the value of the e factor for the WWII fighters was typically somewhere around 0,75 just like Raymer uses in his simplified analysis.

AS accurate as your trying to be in your comparison of a 1/6th wooden model spitfire to the actual FW-190 aircraft??

You cannot use a wooden model in comparison to an actual aircraft for exact numbers!

Post your reference for Pope!
I guarantee he does not say what you are trying to have us believe.

Crumpp

[gripen]

Originally posted by Crumpp
You need to study up more on the Ta-152 program.  Prototypes were flying in 1943 Gripen as were the FW-190A9 prototypes.

There were no completed Ta 152 prototypes before summer 1944. Besides it's up to you to prove full scale wind tunnel testing of the Ta 152.

Originally posted by Crumpp
AS accurate as your trying to be in your comparison of a 1/6th wooden model spitfire to the actual FW-190 aircraft??
...
You cannot use a wooden model in comparison to an actual aircraft for exact numbers!

As noted several times earlier, only you are making comparisons here. This thread is about determination of the e factor not about comparisons.

Originally posted by Crumpp
Post your reference for Pope!
I guarantee he does not say what you are trying to have us believe.

A. Pope (1947): "Wind-Tunnel Testing" p. 274-275:

"It has been observed that (Fig. 7:8) that, when Cl^2 for a given airplane is plotted against total drag coefficient Cdt, the graph is nearly a straight line. Further, since we may write.. [formula]...it becomes apparent that the slope of the line dCd/dCl^2 may be used to find e. (See also Sect. 5:2) Fortunately the slope of this line is practically independent of Reynolds number and a wind tunnel test may hence be used to determine full scale e."



Basicly the size of the model has very little effect to the slope of the line. Therefore scaled models can be well used to determine e. It can be also seen that the differences in the Cd0 do not cause differences in the slope of the line.

gripen

[Crumpp]

Since you have been busted before taking things out of context and only including the portions that support YOUR claim but not including the conclusions which are contrary, Gripen, please just post the page/paragraph.

There were no completed Ta 152 prototypes before summer 1944. Besides it's up to you to prove full scale wind tunnel testing of the Ta 152.

http://users.belgacom.net/aircraft1/avion1/64.html

* Tank continued to tweak the inline-powered designs, resulting in the "Ta-152" series, with work along this line begun in late 1942. The "Ta" stood for "Tank", in honor of his contributions to the Reich. A confusing number of different Ta-152 variants were considered or built in prototype form in 1943 and 1944, converging on two types, the short-wing "Ta-152C" and the long-wing "Ta-152H", where the "H" stood for "Hoehenjaeger (High Altitude Fighter)."

http://www.faqs.org/docs/air/avfw190.html#m5

Common misconception Gripen.  The Ta-152 prototypes as well as the FW-190A9 prototypes were flying in 1943.

Crumpp

[gripen]

Originally posted by Crumpp
Since you have been busted before taking things out of context and only including the portions that support YOUR claim but not including the conclusions which are contrary, Gripen, please just post the page/paragraph.

The source is claimed, get the book if you don't want to believe the direct quote and the graph.

It's up to you to prove that Pope is wrong.
 

Originally posted by Crumpp
Common misconception Gripen.  The Ta-152 prototypes as well as the FW-190A9 prototypes were flying in 1943.

From Baugher's site:

"The first Ta 152H prototypes were completed in the summer of 1944."

Common misconception is in your sources; while the Fw 190C prototypes were used in the developement of the Ta 152 and were flying 1943 in addition to Fw 190 V32 (Ta 153 test plane), these all had standard Fw 190 wing at that time. First true Ta 152 (W.Nr. 150001, CW+CA) was completed June 1944.

Besides your source contains clear errors, there was no prototypes of the Ta 152A and B.

gripen

edit: There seem to had been be couple Ta 152B protypes completed 1945 but no Ta 152A prototypes.

[Crumpp]

Common misconception is in your sources; while the Fw 190C prototypes were used in the developement of the Ta 152 and were flying 1943 in addition to Fw 190 V32 (Ta 153 test plane), these all had standard Fw 190 wing at that time. First true Ta 152 (W.Nr. 150001, CW+CA) was completed June 1944.

My source is:

http://www.schifferbooks.com/newschiffer/book_template.php?isbn=0764318764

April of 1944.  Plenty of time to use any windtunnel in Europe.

besides your source contains clear errors, there was no prototypes of the Ta 152A and B

Another wrong statement.
Try FW-190V20.

t's up to you to prove that Pope is wrong.

Popes not wrong.  You are.  I am certain you are either quoting out of context  or as you did before just plain leaving the part you don't want out.  If you were not doing so it would not be a big deal to just post the page and underline it.  I will get the book, post it myself.

Crumpp

[Badboy]

Originally posted by gripen
Yep, so the viscous part of the drag is missing and we can't calculate e factor for the wing.

They state that even though the theory from which the data was derived is linearised and relates to inviscid flow, those restrictions are known to be relatively unimportant for most practical purposes in calculating the lift and lift-dependent drag. It does give you the e value for the wing, within those limitations.

Originally posted by gripen
Wood's system to estimate the effect of the fuselage is based on NACA 236 which is a compilation of tests results on various fuselage, nacelle etc. data from year 1927. In most of these tests there was no tail surfaces in the fuselage and the effect of the interference drag is not counted.

Yep, as Wood states on page 66 of his book. However, all I meant was, that they both used the same approach in terms of finding a value for the wing separately from the fuselage, not that they used exactly the same methods to do so, sorry, I should have made that clearer.

If you would like a copy of the report and the software, let me know?

Badboy

[MiloMorai]

Originally posted by Crumpp

quote: besides your source contains clear errors, there was no prototypes of the Ta 152A and B

Another wrong statement.
Try FW-190V20.

Not just the V20 (W.Nr. 0042, TI+IG) but also the Fw190 V19 (W.Nr 0041) and Fw190 V21 (W.Nr 0043, TI+IH).

These 3 a/c  were produced at Adelheide for the testing of the planned Ta 152A series.

However, the 2 planned prototypes for the Ta 152 A-1 (TA 152 V1, W.Nr 250 001 and Ta152 V2, W.Nr 250 002) with the new 19.5 m2 wing were cancelled.

Harmann's Ta 152 book p 23

[gripen]

Originally posted by Crumpp

April of 1944.  Plenty of time to use any windtunnel in Europe.

April 1944 is not 1943. Besides it's up to you to prove that the Ta 152 prototype was tested in the full scale wind tunnel, not that some kind of prototype existed june or april 1944.

Originally posted by Crumpp
Popes not wrong.  You are.  I am certain you are either quoting out of context  or as you did before just plain leaving the part you don't want out.  If you were not doing so it would not be a big deal to just post the page and underline it.  I will get the book, post it myself.

Well, you are most wellcome to do so if you don't want to believe me.

Originally posted by Badboy

They state that even though the theory from which the data was derived is linearised and relates to inviscid flow, those restrictions are known to be relatively unimportant for most practical purposes in calculating the lift and lift-dependent drag. It does give you the e value for the wing, within those limitations.

As noted earlier in this thread, also the viscous drag of the wing increase simultaneously with the rise of the induced (lift related) drag when the Cl (or AoA) increases. And to determine e factor we need to count this part of drag rise too.

As an example we can use Wood's formula for rectangular wing and compare it to Glauert corrected data for same wing type (assuming AR 6):

Wood  => e=0,86 (induced and viscous)
Glauert => u=0,94 (only induced)

Note that I use Anderson's induced drag factor u which is used same way as e.

gripen

[Crumpp]

April 1944 is not 1943. Besides it's up to you to prove that the Ta 152 prototype was tested in the full scale wind tunnel, not that some kind of prototype existed june or april 1944.

No it is not Gripen.  As I said before I have the full report.  April is plenty of time to fly for an hour and spend a day or two at the wind tunnels in France.

Crumpp

[gripen]

Originally posted by Crumpp
No it is not Gripen.  As I said before I have the full report.

Well, then just post the evidence that the Ta 152 was tested in the large scale wind tunnel.

gripen

[Crumpp]

Gripen says:
Well, then just post the evidence that the Ta 152 was tested in the large scale wind tunnel.

Gripen says:
The source is claimed, get the book if you don't want to believe the direct quote and the graph.

Crumpp says:

If you want the report go to the archives and dig through the index card list and find your own copy.

My credibility is intact, Gripen.  I am not the one who has been busted quoting selected parts of data to advance an agenda. Or advancing ridiculus theories of my own.


Crumpp

[gripen]

Originally posted by Crumpp

If you want the report go to the archives and dig through the index card list and find your own copy.

So I quess this claim is again in the same category as the "wet lifting area" ie you are talking about a thing which does not exist.

Originally posted by Crumpp
My credibility is intact, Gripen.  I am not the one who has been busted quoting selected parts of data to advance an agenda. Or advancing ridiculus theories of my own.

Unlike you I have identified my sources and anyone can check them if needed. Besides from above anyone can find a good example of your quoting in the case of the NACA 921.

gripen

[Crumpp]

Unlike you I have identified my sources and anyone can check them if needed. Besides from above anyone can find a good example of your quoting in the case of the NACA 921.

Well do it.

Only source I have not released is this report.

Gripen says:
I quess this claim is again in the same category as the "wet lifting area" ie you are talking about a thing which does not exist.

Crumpp says:
Exactly. Why is that? Because the taper ratio for the Spitfire is impossible to nail down since the wet lifting area  in no way matches the elliptical shape of the wing due to the wing twist destroying the benefits of the elliptical tips. That leaves a wide margin that delivers correct values that are meaningless in the real world. Very open to data manipulation.

No Gripen I was talking about the lift distribution and confused the terminology.  Unlike you I have never represented myself as an expert.  

Lets Check out your claims:

1.  All aircraft have the same e factor ".8"!

2.  You did not realize that the differences in values comes from an element of parasitic drag.  Niether did I until Badboy pointed it out.

3.  Your ridiculous calculations off Lednicers lift distribution chart.  The one three aeronautical engineers working in the field could not figure out how you could make any conclusions about efficiency factor.

4.  Your repeated insistence in using skewed data even when undisputable proof is laid before you.

5.  Your insistence then that the aircraft finish was not representative even when presented with undisputable proof.

6.  When the math did not go your way you started this ridiculous thread offering a "prize" looking for help for the other thread!

Posting my documentation will NOT prove anything to you.  You will continue with your agenda no matter what anyone else says or produces.  Badboy has tried to square you away and you argue with him still!

Only thing it would do is give you the benefit of my time and money spent researching it.

Crumpp

[g00b]

Regardless of the conclusions they draw, Gripen and Badboy are capable of well-mannered and intelligent discourse and reasoning out their differences.

Crumpp and Dweeb could use a serious lesson from Miss Manners. You come across as frothing zealots who continually twist others words and meanings so that even if you have a point it's hard to take you seriously.

I know nobody gives a rats bellybutton what I think but I just wanted to let you all know how you come across to the random passer-by.

Stick that in your pipe!

[gripen]

Originally posted by Crumpp
Well do it.

Let's look it again, below is Crumpp's version (his post 01-04-2005 12:50 AM) of the NACA 921 which was supposed to support Wood's claim on validity of the Glauert corrections for tapered wings:

"For studies requiring a higher degree of accuracy, lifting-surface theories have been used [as opposed to lifting line theory], but generally it has been found that the additional complexity of these methods has not sufficiently improved the predictions to warrant common use." (NACA Report 921 - Theoretical Symmetric Span Loading at Subsonic Speeds for Wings Having Arbitrary Plan Form)"

Let's see again the whole quote, keep in mind that mentioned modifications for lifting line theory actually mean Glauert corrections:

"Lifting-line theory in the past has been so modified and extended so that the characteristics of wings having no sweep, moderate to high aspect ratio, and any taper ratio can be determined readily with good accuracy. For studies requiring a higher degree of accuracy, lifting-surface theories have been used [as opposed to lifting line theory], but generally it has been found that the additional complexity of these methods has not sufficiently improved the predictions to warrant common use."

So actually the quote says that Glauert corrections for the lifting line theory work well which is exactly opposite Crumpp wanted to prove.

Originally posted by Crumpp
Only source I have not released is this report.

Well, I don't see any proof here that such report on the Ta 152 exist.
 

Originally posted by Crumpp
No Gripen I was talking about the lift distribution and confused the terminology.  Unlike you I have never represented myself as an expert.  

Well, I wonder what are you doing in this thread then because you seem to have no clue what you are talking about.

 

Originally posted by Crumpp
Lets Check out your claims:

1.  All aircraft have the same e factor ".8"!

Such claim I have not done.

Originally posted by Crumpp
2.  You did not realize that the differences in values comes from an element of parasitic drag.  Niether did I until Badboy pointed it out.

As pointed out above I have told you nearly two months ago that lift distribution analysis (like Glauert corrections) do not count viscous part of the drag rise (see my posts 11-12-2004 09:17 PM and 11-15-2004 02:42 PM) so I have known perfectly well that e factor contains induced and viscous drag long before Badboy posted something on this.

Originally posted by Crumpp
3.  Your ridiculous calculations off Lednicers lift distribution chart.  The one three aeronautical engineers working in the field could not figure out how you could make any conclusions about efficiency factor.

As pointed out earlier, there is certainly a strong correlation between lift distribution an efficiency factor and that was what I calculated with good results. Or do you have some kind of evidence that there is no correlation between e factor and lift distribution?

Originally posted by Crumpp
4.  Your repeated insistence in using skewed data even when undisputable proof is laid before you.

I wonder what are you talking about here.

Originally posted by Crumpp
5.  Your insistence then that the aircraft finish was not representative even when presented with undisputable proof.

Nothing to do with this thread and that case I was just quoting a source you self use.

Originally posted by Crumpp
6.  When the math did not go your way you started this ridiculous thread offering a "prize" looking for help for the other thread!

It has been pointed out in this thread that there is no way to calculate e factor from the aspect ratio only.

Originally posted by Crumpp
Posting my documentation will NOT prove anything to you.
Only thing it would do is give you the benefit of my time and money spent researching it.

So far you have not posted anything relevant for this thread so I wonder why you keep posting.

gripen