Russian Airfoils Data

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ultralights

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I wonder if anyone knows the data for the following Russian airfoils:

TsAGI R-3a (or CAGI R-III A-15?)
TsAGI P-III-12
TsAGI P-IIIA-15

searching the internet I was able to achieve the following links:


Airfoils characteristics and coordinates
TsAGI R-3a (12%) (tsagi-r-3a-il)


I want to get more accurate data and the original reports with the exact coordinates it is possible to draw profiles.
(leading edge radius, slope LE radius or equation for generation the airfoil,etc)
 
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wizzardworks

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ultralights, Go to airfoiltools.com scroll down to click T on left side and down the page to tsagi airfoils. Click the airfoil and get the ordinates on the right side of the page.
There are several styles and I use Selig data files as an example. Scroll down the page to find the polars graphs.
Another site is Worldofkrauss.com which is a recently rebuilt database and may have some periods of downtime. Also the UIUC.ae.com site from the
aeronautical department of the University of Illinois has airframe useage for airfoils and links to other sites.
wizzardworks
 

pwood66889

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Russian "P" is English "R".
And thd C is the English S; B is the English V.
The Russian A, M and T are the same as the English. O is similar. E has the "Y-glide" to it.
Saint Cyrl based the Russian Alphabet ("Cyrlic") on the Greek, then made up glyphs for the ones left over = Hard and Soft Signs, and so on.
Percy, who took Russian at the hight of the Cold War figuring either the US would take them over, or the "Filthy Commies" would take US over!
 

ultralajt

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Russian "P" is English "R".
Thats why P-III equals R-III and P-3 and R-3.... depending on what origin is the printed source for the airfoil.

P-III airfoil was used on vintage russian biplace record breaking sailplane Stahanovec.

On many Russian forums I found out that airfoil P-III is very popular even today. Almost any ultralight or light plane/glider uses that airfoil. And as far I was able to observe Aeros Rigid Wing Phantom, even his airfoil seems to be pretty close to the P-III....and that gives a clue (I am not sure but suspect) also about Alatus AL-12 ultralight sailplane airfoil, as D box is taken from Phantom D-box molds.

Mitja
 

ultralights

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Ok, tank very much.
Then:

TsAGI R-3a = CAGI R-III A-15 = TsAGI P-IIIA-15

007-01.gif

I want to get more accurate data and the original reports with the exact coordinates it is possible to draw profile.

I have only this few ordinates:

X %
Yupper %
Ylower %
0
0
0
0,5
1,98
-0,91
1
2,8
-1,29
2
4,16
-1,75
3
5,24
-2,03
5
6,98
-2,35
7
8,34
-2,51
10
9,87
-2,65
15
11,41
-2,77
20
12,02
-2,82
25
12,16
-2,82
30
11,92
-2,8
40
10,665
-2,61
50
9,05
-2,3
60
7,28
-1,95
70
5,46
-1,52
80
3,64
-1,04
90
1,82
-0,52
100
0
0
 

Norman

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Those are enough to draw the airfoil, especially if you're doing it by hand. I typed them into Profili and interpolated so that the program has more panels to analyze but didn't do anything more, except remove one point from the mean line near the leading edge. The spline fitting algorithm sometimes has trouble near the LE and you have to remove some points manually. It's the program's fault not the coordinates you have. What you've shown is actually unusually smooth for coordinates produced in the '30s.
 

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wizzardworks

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ultralights, The Selig data file at airfoiltools.com has 251 pairs of coordinates for this airfoil displayed to 4 decimal places. Also the MH80 airfoil at 12.72 percent thickness is very similar.

wizzardworks
 

ultralajt

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I made a mix of FX77-153 and P-III airfoils to get apropriate airfoil for my UL Sailplane, and I am pleased with a result!

MIXofAirfoils.jpg

I will try to attach P-III airfoil coordinates here: View attachment R-3.txt
First column=X
Second column=Y

Mitja
 
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ultralights

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ultralights, The Selig data file at airfoiltools.com has 251 pairs of coordinates for this airfoil displayed to 4 decimal places. Also the MH80 airfoil at 12.72 percent thickness is very similar.
wizzardworks, airfoiltools.com link is in first thread post, this is for a 12% R-3 airfoil. CAGI R-III A-15 is a 15% airfoil, this one not are in airfoiltools.com database.

I made a mix of FX77-153 and P-III airfoils to get apropriate airfoil for my UL Sailplane, and I am pleased with a result!

I will try to attach P-III airfoil coordinates here:
Mitja, P-III have different airfoil coordinates that P-III-A. P-III-A appears to have better properties. Very interesting the comparison that Wortman airfoil.

About coordinates I working with Rhino nurbs grade 3 for interpolate points. But LE always is a problem. I think that a LE with upper and lower curves tangent to the perpendicular to mean line is a good aproximation to original airfoil basic equation. I have not the original polinomial equation.

Norman, I search for wind tunnel experimental data of Tsagi airfoil for comparison that NACA four digit series from 1.5 to 5.0 million Re.
I think that TsAGI P-III-A have good low Cm and good hight Cl with gentle stall characteristics. This airfoil appears are a good combination between a four and a five digit NACA airfoils.

Большое спасибо!:)
 
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ultralights

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The Incomplete Guide of Aircraft using CAGI R-III-A Airfoil

3Xtrim
3X47 Ultra
3Xtrim
3X55 Trener
Argo-02
Argo-02
Aeroprakt
A-19
Aeroprakt
A-20
Aeroprakt
A-21 Solo
Aeroprakt
A-22 Valor
Aeroprakt
A-23 Dragon
Aeroprakt
A-24
Aeroprakt
A-26
Aeroprakt
A-28
Egorich
Egorich
Emelyanov
KIM-3 Stakhanovets
Chernov
Che-22 Corvette
Chernov
Che-25
Crystal
Crystal
Optimist
Optimist
Politechnika Warszawska
PW-3 Bakcyl
Politechnika Warszawska
PW-4 Pelikan
Politechnika Warszawska
PW-8
Remos
Mirage G3
Zelik-2
Zelik-2
 

Norman

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But LE always is a problem. I think that a LE with upper and lower curves tangent to the perpendicular to mean
Profili produced a 274 point .DAT file from the interpolated spline that these polars are based on. If you want it you can have it but as I said the small set you have is good enough for drafting. If you're having a problem getting Rhino to do a fair curve then maybe it would be helpful but if you have to type them all in it can be a real chore especially since 1/2 of them are negative numbers.

I search for wind tunnel experimental data of Tsagi airfoil for comparison that NACA four digit series from 1.5 to 5.0 million Re.
I think that TsAGI P-III-A have good low Cm and good hight Cl with gentle stall characteristics. This airfoil appears are a good combination between a four and a five digit NACA airfoils.
It does have a Cm between the NACA 4 and 5 digit airfoils and slightly better lift and drag than the closest 4 digit section. I can't say anything about the stall though because panel codes like Xfoil don't give accurate results past CLmax. For instance I haven't been able to get any of the programs that use Xfoil as the back-end processor to replicate the sharp stall break of the NACA 5 digit airfoil sections that wind tunnel data shows. I should also explain that the polars I've been posting are fixed weight rather than fixed Reynolds number. Here's an excerpt from the Xfiol manual:

* Type 2 corresponds to an aircraft in level flight at a given altitude
undergoing trim speed changes. This is the most useful airfoil polar
form for determining a drag polar for an aircraft at 1-g. For this case,
The "Mach number" input with the MACH command is actually interpreted
as the product M sqrt(CL), and the "Reynolds number" input with the
VISC or RE commands is actually interpreted as RE sqrt(CL). For a wing
in level flight, these products can be computed from the following exact
relations, with Re based on the mean chord:

1/2 1/2
| 2 W/S | 1 | 2 rho W |
M sqrt(CL) = | --- --- | RE sqrt(CL) = -- | ------- |
| 1.4 p | mu | AR |

W = weight p = ambient pressure
S = wing area mu = dynamic viscosity
AR = aspect ratio rho = ambient air density
If you do manage to find wind tunnel data on the TsAGI-R-IIIa it will look completely different from these but if there are curves for the range of Re you expect to fly at you can connect the dots and use the stall of the lowest Re to finish out the curve. The result will be similar to what I've plotted for you but with an accurate curve after CLmax.
 

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ultralights

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... but if you have to type them all in it can be a real chore especially since 1/2 of them are negative numbers.
This task is very simple in rhino and autocad, you only select "multiple points" and "copy and paste" all ordinates one time (comma separate).;)

Thank very much for your XFoil run.:)

I'm trying to reach Politechnika Warszawska people to obtain wind tunnel data.
 

wizzardworks

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ultralights. When plotting airfoils you must start at the trailing edge and continue around the leading edge back to the trailing edge. Leave out the final pair at the trailing edge and connect with a line. I use Rhino
and the procedure is to draw the vertical and horizontal X and Y axis and use the offset command in a different color and put a small circle on the intersections. This allows single point entries rather than starting over
with a wrong coordinate entry. Some ordinate formats repeat the X ordinates on the bottom as used on the top side. Leave those offsets to reduce data input. Then draw the airfoil using control point curve with only the
center object snap turned on. If you have 12 percent thickness ordinates plot them and use transform/scale/2diminsional/unequal to scale the Y direction by 1.25 and leaving the X at 1.0 That would draw the airfoi
l but you would need to find the polars elsewhere. I also move the decimal point two places right to draw the airfoil with a 100 inch chord. Then you can scale the result to any chord you like. You can also make an
array of the Y axis at 2 inch offsets, then trim off the excess with the airfoil curve as the cutting object. Then draw a control point curve thru the remaining vertical line segments with only the midpoint object snap
on and you will have the camber line. This would then be measured at the highest point off the chord to find the percent camber of the airfoil.
wizzardworks
 

ultralights

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ultralights. When plotting airfoils ...

Dear wizzardworks,
In this airfoils families, Ordinates of the cambered lying sections are obtained by laying off the thickness distributions "perpendicular to the mean lines".



Because this, scale in one direction, plot mean line by midpoint "Y" ordinates and anything else of this type is only misinterpretation about airfoil section generation and the plot that you obtain is not any related airfoil.:depressed

In rhino you have several tools that "point" for snap point, and multiple point draw simply paste ordinates from database for not generate mistakes in individual data entry.:)
 
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wizzardworks

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It is my understanding that cambered airfoils are the result of modifying a symetrical base airfoil. The modification is done by plotting the camber line and then adding the vertical measurement to both
the upper and lower surface coordinates. There are a variety of forms used for the camber line according to how forward the maximum thickness or loading is positioned. The leading edge radius shown
above is WRONG. There is no leading edge radius. This was a result of quick and dirty production of airfoils for war time wind tunnel testing. They were looking for relative performance of airfoils on very
low aspect test specimens and optimal accuracy was not the goal. Harry Ribblett has more on this in his book. I may be wrong but I thought the mean line is determined from perpendiculars to the airfoil
surface and is more like the neutral axis of a beam??
I need to find out how the cut and paste multiple point selection is done. Does the file get edited with commas between the columns of data or just pick a file that starts with the trailing edge?

wizzardworks
 

ultralights

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I may be wrong but I thought the mean line is determined from perpendiculars to the airfoil
surface...
Yes!!!, by this you can not draw several offset Y axe and use midpoints between ordinates. The figure about airfoil section ordinates generation is from "Theory of Wing Sections" book of Abbott. Harry only play with a CFD software with many limitations, (Riblett airfoils (Walter Lounsbery, David Lednicer, "highflyer")) NACA working 30 years with thousands wind tunnel testing hours. Today CFD is more powerfull to save work time in tunnel, but experimental wind tunnel data confirmation remains essential.

I need to find out how the cut and paste multiple point selection is done. Does the file get edited with commas between the columns of data or just pick a file that starts with the trailing edge?
For Rhino multiple coordinate data entry:

Select and Copy from archive text(notepad, word, excel, etc) the x,y coordinates separate by comma in colum.

In Rhino window select curve-point object-multiple points
in cursor line paste the selected coordinates
in object snaps enable only "points"
in Curve select -free forms-interpolate points
Begin to draw from trailing edge, point to point around airfoil
If trailing edge have only one point, before clicking this last point type "s" in cursor line (and enter)
pick the last point. Ready!
 
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