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        Help! Goettingen 580 airfoil coordinate

#1 suirendoujin May 13, 2008 08:47 AM

Goettingen 580 airfoil coordinate
 
I need it to design a wing for my current scale sailplane project. Coordinates for this particular airfoil was not in UIUC database, Compufoil, or in any of books I have. Would appreciate any info. TIA.

#2 Thermaleer May 13, 2008 10:26 AM

suirendoujin, I could not even locate this airfoil in Profili 2.18. Google did not show up anything obvious, looks like this one will be tough. Joser

#3 suirendoujin May 13, 2008 06:18 PM

Thermaleer, Yes, this one IS tough. Goettingen airfoil numbers are numbers given in sequence to an airfoil design, so you have to get hold of the actual coordinates or an accurate drawing. I am hoping European modeler can help me out.

#4 Thermaleer May 13, 2008 11:46 PM

What aircraft was it used on? Maybe it can be lofted from a set of drawings?

#5 suirendoujin May 14, 2008 08:45 AM

This airfoil was used on Kyutei Type 5. A vintage sailplane with historic significance here in Japan. Made the first over an hour flight, auto-tow and aero tow. My build thread is here, http://www.rcgroups.com/forums/showthread.php?t=815703
There is a drawing of the airfoil in one of the 3 views I have. Unfortunately, its only 37 mm in chord, so in order to use it I must blow it up ten times. :eek: So much with accuracey. :o Goettingen 580 does look vaguely? similar to thickened Eppler 214. So, I f I cannot obtain coordinates, then will have to take an alternative approach.

#6 ghostofpf1 May 14, 2008 10:32 AM

Assuming that's the fullsize gliders foil...
From what I've read scale foils don't always fair well at modelling sizes.Have you considered using something similar but designed for our reynolds numbers spread ??
HTH
Ghost

#7 Lance Prior May 14, 2008 10:45 AM

You may want to consider a thick high camber HQ airfoil.

#8 Bernd Brunner May 14, 2008 03:05 PM

1 Attachment(s)
Or may be a sd7062 (thinned to 12%). IMO itīs not necessary to add more drag by using too thick airfoils. The Re-numbers will be at least 150k or 200k.

Bernd

#9 Lance Prior May 14, 2008 03:42 PM

I suggested thick purely for scale appearance.

Looking at the drawing the foil appears to be about 15% thick or more.

#10 lincoln May 14, 2008 05:18 PM

Is the University still there? That's where the airfoil came from, isn't it? If so, perhaps if you can find a German speaker you can find it and they'll just give you the coordinates. A lot of trouble, I suppose. Perhaps they even have all those coordinates on a web site?

#11 suirendoujin May 14, 2008 06:16 PM

Thank you all for your input. Goettingen 580 was used on full scale. At quarer scale, I thought, well, was hoping, to get away with it, biased more to scale appearance than performance.

#12 jcpatrick May 14, 2008 09:40 PM

1 Attachment(s)
suirendoujin - What happened to Hiroshi Takeuchi's NASG Airfoil Database? There were a lot of Gottingen airfoils there, and now the site is gone.

Here is a comparison of the airfoil you posted, the SD7062 Bernd suggested, and a Drela airfoil designed for hand launch gliders. You might want to try this one. If you find the 580 coordinates or data, I'm sure someone will help you make some airfoil drawings.

#13 suirendoujin May 15, 2008 09:25 AM

Well, based on the rather simple, if not crude airfoil shape provided with the 3 views I have, it looks like Goe 580 had a 13.5 % thick airfoil. If I can modify the coordinates of AG27-13% by thinning it to say, 12 % and giving it Philips entry, I might have an airfoil which might be a nice compromise between scale looks and performance. Thank you jcpatrick. I will probably reach a verdict? on Monday.

#14 Lance Prior May 15, 2008 12:04 PM

Are you talking about taking an AG27 and making it 13% thick?

You would probably be better off to use an airfoil that is designed to be the thickness you require instead of making a thin one thick.

#15 Bernd Brunner May 15, 2008 01:52 PM

suirendoujin, what do you mean with "scale appearance"? Wouldnīt you fly the model, is it static? May be you can ask Loopingfred about the airfoil he has used on his KA-3 (2.5m; scale 1:4). By the way, i have looked at the polars befor i recommended the modified SD7062.

Cheers,
Bernd


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