I justed wasted an hour carefully tracing the rib drawing only to discover that the dimensions that are supposed to be held closely are pretty far off in the printed plans, and the bottom rib is not nearly a straight line. I am sure many of you have had similar experience... At this point I'd just as soon manually draw the airfoil from the numbers (I have no CAD experience or access). Unfortunately, I am not sure where to find them. I searched past posts, but no luck. (I am not confident I am getting access to everything I should be - pilot error most likely.)

Does anybody have an excel/ascii/word file of the airfoil ordinates (for the EROS). I'm sure I can come closer by hand than the reprinted plans offer... Thanks!

Tony

Tony,  A lot of us had this problem.  What I did was start with a straight line on a large sheet of paper, mark off all the fixed points from the plans.  I then had photocopys made of the rib drawing, cut them up and pieced them together on my new layout.  It should come out close with all the critical points where they need to be.  Then just adjust the top curve to a smooth curve that estimates the original.  As long as all your ribs are the same and your spars are in the correct place it will be fine.

Yeah, I had similar issues with the rib drawing and asked the same questions.  I ended up just making sure that the "hard points" were correct such as straight on the bottom, and spars perpendicular to the bottom, etc and used the drawing as an approximation.  Like Randy said, as long as your ribs are all the same that is the main thing.  They need to match each other in order to get a nice square wing assembly.

Pete

One time I asked Wayne what airfoil he used. He answered "LP 10". I said "LP 10?"  "Lead pencil 10th try". He replyed.

    "Bat Cave" Dave

Ok fair enough. I'm not worried about it flying if I am off a bit with the airfoil. But not having a real sophisticated understanding of aerodynamics I was only concerned that changing the airfoil a bit might alter some of the subtle flying characteristics of the wing such as how the center of pressure moved at various angles of attack, or stall characteristics, etc. But I'm willing to go with LP 10.tp or whatever... I saw earlier that some folks created rib drawings with CAD, so I assumed someone must have the ordinates. Maybe if I had said I was going to create CAD drawings someone would have offered them?... No big deal really. It'll fly... Thanks for your insights. If it is good enough for you guys, I am sure it will work for me... Hope to get my jig done before the weekend... - Tony

When I got My Plans, they came with a two piece full size rib drawing. The instruction said hold this length and gave a measurement, and make the bottom stright. Do they not send this anymore. I would be glad to loan, but right now I am building another and need my rib jig. charlie

Hi Tony,

I am in the same boat as you for the actual dimensions. I have a .dxf that Ari shared with me, I can pull some measurements for you but I can't verify them (the reason I didn't share earlier). It seems that Team or JDT were a little shy on information and counted on full scale prints to actually build with unless I missed something.

Ari, if you are monitoring this thread, how did you come up with the .dxf's and do you mind me sharing?

Dennis

Dennis:
Thank you for your offer. I wasn't meaning to criticize anyone for not sharing. And I do appreciate both your hesitancy to share info you can not verify, and your willingness to share what you have. I'll gladly accept your offer of measurements if it doesn't require a whole lot of effort on your part. Thank you... I too am curious as to where folks arrived at numbers for .dxf if JDT/TEAM hasn't provided them.

I don't expect my airfoil to be perfect. My construction skills are not that refined. But my ribs will all be the same, and I'd just like to be as close as I can within reason. If we knew closest airfoil model we could probably find coordinates on the Web.

This certainly isn't a huge issue from my perspective. But I am a little surprised it hasn't been resolved more precisely during the last 12 years.  That is not a criticism of JDT or Eros builders in any way. Just my naiive perspective... Thanks again for everyone's replies.

Tony

I kept going back and forth about my DXF drawing, whether I should talk about it here or not. Tony was very specific that he didn't want to deal with CAD, and I didn't want to offer him something he didn't want. I can understand not wanting to learn yet another technology. It took me years to give in and learn CAD, and it always annoyed me that people would post DXFs in forums like this one and I couldn't read them. This said, I'm happy to post the file here if anyone finds it useful.

The way I came up with the ordinates was not very scientific. I tried to build my rib jig around the full-size drawing, which as we all know by now, is impossible. So I scrapped the first jig and started with a clean piece of paper (literally) on which I drew the dimensions I was supposed to hold. This wasn't difficult, just frustrating because I had to adjust my expectations about plans quality. This was before I decided to go CAD. You can see photos of all this on page 1 of my build log thread (http://www.lonesomebuzzards.com/cgi-bin/forum/Blah.pl?m-1185574047/s-0/)

After I built all my ribs, I needed to cut plywood sides for root and tip ribs, and by then I'd decided to use CAD and CNC. But now I was stuck with 24 ribs that were based not on any kind of airfoil ordinates but on a freehand approximation of the "hold this" dimensions. I should have gone CAD from the start! If I had, I could have taken NACA 23012 coordinates and worked from them, but now I was stuck with "reverse-engineering" my completed ribs. So I traced one of the ribs, drew verticals every inch and measured their heights.

All said and done, the rib outline is the least useful part of my CAD effort. With that in mind, if anyone wants to use it for any purpose, I have no objections.

Ari.

IANAL:
    This drawing is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

I can start to appreciate Mr. Ison's plight (legal issues only, I can't even approach his level of genius).

Dennis

Quoted from iter

I kept going back and forth about my DXF drawing, whether I should talk about it here or not. Tony was very specific that he didn't want to deal with CAD, and I didn't want to offer him something he didn't want. I can understand not wanting to learn yet another technology. It took me years to give in and learn CAD, and it always annoyed me that people would post DXFs in forums like this one and I couldn't read them. This said, I'm happy to post the file here if anyone finds it useful.

The way I came up with the ordinates was not very scientific. I tried to build my rib jig around the full-size drawing, which as we all know by now, is impossible. So I scrapped the first jig and started with a clean piece of paper (literally) on which I drew the dimensions I was supposed to hold. This wasn't difficult, just frustrating because I had to adjust my expectations about plans quality. This was before I decided to go CAD. You can see photos of all this on page 1 of my build log thread (http://www.lonesomebuzzards.com/cgi-bin/forum/Blah.pl?m-1185574047/s-0/)

After I built all my ribs, I needed to cut plywood sides for root and tip ribs, and by then I'd decided to use CAD and CNC. But now I was stuck with 24 ribs that were based not on any kind of airfoil ordinates but on a freehand approximation of the "hold this" dimensions. I should have gone CAD from the start! If I had, I could have taken NACA 23012 coordinates and worked from them, but now I was stuck with "reverse-engineering" my completed ribs. So I traced one of the ribs, drew verticals every inch and measured their heights.

All said and done, the rib outline is the least useful part of my CAD effort. With that in mind, if anyone wants to use it for any purpose, I have no objections.

Ari.

IANAL:
    This drawing is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

why not just use the published naca 23012 data? besides at minimax speeds the exact airfoil shape is not as important as having the spar be the correct height etc.  between the ribs what is the airfoil shape?

Quoted from CFBTB

why not just use the published naca 23012 data?  as having the spar be the correct height etc.

14% thickness

Wow. Again, I really appreciate everyone's interest, comments and responses... Be assured, I have nothing at all against CAD. In fact, I really respect and admire those of you who have gone to the effort of creating CAD drawings, and especially of moving to laser cutting parts. Under different life circumstances, or if I had easy access to CAD and laser cutting technology it might seem worth it for me to take time to learn CAD now. However, thats not my current situation, or really where my current intrinsic interests lie in regards to this project.  For now, I'm happy relying on my relatively low-tech aircraft building skill-set.

I only mentioned CAD because I suspected that CAD drawings must be based on actual ordinate numbers(or relative transformations thereof), and if I had those numbers I could hand draw an airfoil that would be plenty close enough. Apparently my assumption was wrong. I now understand that those of you, or at least Ari, who have DXF drawing for the ribs had to reverse engineer your own manual efforts at working with the original drawings.

All that said, now that I know the airfoil is close to published 23012.  As "bear" suggested, I'll just look those up and go from there. Thats all I was requesting really.

Again, thanks to everyone. I don't want to steal anyone's hard work. I just assumed the ordinates must be floating around for a 12-year old design of interest to a cooperative and collaborative group of folks that max builders seem to be. It was only meant to be a simple request to learn from those ahead of me. -Tony

I'd be very careful about those statements "I'm not worried about the airfoil being off a little bit." Pretty soon one might not worry about that glue joint, seems about right, it's only an airplane. Catch the drift?

Bob, with all respect, I think you are making a big leap regarding my statement... The purpose of my original post, and the nature of the entire thread was that my aim was to come as close is as reasonably possible to the desired airfoil, (otherwise, why did I even bother posting request for correct ordinates once I realized the plans drawing was off?) recognizing that, if it requires doing the best I can to work with the imperfect plans, I would. The very next sentence in the post you quoted explicitly states that my concern is that I did not want to alter flying characteristics of the wing. In my opinion, your implication is based on quoting me out of context...

now off to buy some Elmer's glue for those joints  ;-)

Tony

Ari - I have a question about how you determined your revised rib jig dimensions. It sounds like your plans were same as mine, i.e., bottom rib not flat and stated dimensions to be held not precise. Like you described, it is easy enough to start from scratch with the specific dimensions that plans say to hold. But then, did you still fit the curvature on the original drawing to your new jig, or did you attempt to adjust for the apparent stretching of the plans some way?... My confusion/concern is that if we can assume the non-straight bottom line and inaccurate dimensions of the plans are due to printing stretch/distortion, then shouldn't we also assume the top curvature of the airfoil on the original plans is likely different from what was originally intended?  

I agree with your comment in your log, either an accurate full size drawing, or an accurate scaled drawing, or just the ordinates would be much less confusing. As the plans are, the specific shape of the airfoil seems up to builder interpretation...  To what extent it matters, who knows. I don't have the expertise to say... But there does not appear an obvious way to "get it right" without knowing the specific ordinates of the originally intended airfoil?

Tony

Quoted from CFBTB

why not just use the published naca 23012 data?

Wane used a modified [sic] section. For one thing, NACA sections don't have flat bottoms the way the MiniMAX plans do. The top line is probably fairly close, but again, the LP-10 is afar better description than NACA 23012.

Quoted from 457

14% thickness

You're absolutely correct, I got the thickness wrong, and I think I got the series wrong, too. It seems the correct airfoil is 4414--thanks making me check.

Quoted from RedBird

Under different life circumstances, or if I had easy access to CAD and laser cutting technology it might seem worth it for me to take time to learn CAD now.

CAD was easier to learn than I thought. If you change your mind, I can tell you that I use a free program called QCAD (http://www.qcad.org). Even if you don't want to learn CAD, you can use this program to print out my drawing at Kinko's. Actually, if you want it, I can mail you my paper drawing, or even the whole rib jig--I'm done building ribs.

Also, I can laser-cut the parts for you--PM me if you're interested.

Quoted from RedBird

I don't want to steal anyone's hard work.

Not at all, I'll be happy if you find it useful. "He who receives a file from me receives instruction himself without lessening mine—as he who lights his taper at mine, receives light without darkening me."

Ari.

Hello Ari,
Appears we were posting to each other simultaneously.... Its not that I don't want to learn CAD, and I could probably blunder my way through it ok, but, my original post was just looking for a quick way to get the airfoil correct, given that I've never bothered to learn CAD, and don't currently have it at my disposal... However, after the discussion here, I realize that what I was looking for probably doesn't exist. I.e. a set of specific ordinates for the original Eros airfoil. Anything out there was likely reverse engineered, along the lines of your efforts.

At this point I'll probably look up a couple airfoils that appear closest (thanks for the revised NACA section), keep the hard points specified in the plans, plot a full sized drawing, and go from there. Just for the sake of it, I might post the ordinates I decide upon, with all disclaimers of course... ;-)

Thanks for your offers. I'll give the laser cutting some thought.

Tony

No problem Tony. I understand where you're coming from, is why I hesitated to post the file in the first place.

I don't think the airfoil matters that much. I'm not building a laminar supersonic record-breaking anything. Imperfections in wood grain and my workmanship will have an effect, and the way fabric stretches over ribs means you can only maintain the airfoil over ribs, anything between them is only an approximation anyway.

I agree however that it's very disappointing to see such sloppy reproduction in the plans. It was a big turnoff for me. The good news is that we both overcame this disappointment. The bad news is that, if my experience is any guide, you'll have more disappointments to overcome as you work through the plans and drawings. You're right, it doesn't have to be this way, and in fact I own other plans by Ison that are much better in all these respects. But nothing can beat the community here, and imperfections in the plans, angering as I find them at times, have always been resolved when I asked about them here.

Good luck with your project. I'm sure that with the care you're giving it it will be a wonderful airplane. I'm looking forward to watching your progress!

Ari.

This site doesn't have a 4414, but here is link with 4415 ordinates. Not sure how close will be to Eros airfoil, but I'll probably check just for fun...

http://www.pdas.com/sections45.htm

Quoted from RedBird

This site doesn't have a 4414, but here is link with 4415 ordinates.

Same thing. One is 14% thickness, the other 15%, just scale appropriately.

Everyting you ever wanted to know about NACA airfoil numbers: http://en.wikipedia.org/wiki/NACA_airfoil

Quoted Text

The NACA four-digit wing sections define the profile by:
   1. One digit describing maximum camber as percentage of the chord.
   2. One digit describing the distance of maximum camber from the airfoil leading edge in tens of percents of the chord.
   3. Two digits describing maximum thickness of the airfoil as percent of the chord.

Ari.

Attached is a csv file (tab delimited) of ordinates based on NACA 4415 with max thickness reduced to 14% of chord length. If I have done this correctly that should make it a NACA 4414. However please note the following disclaimer:

I know absolutely nothing about airfoils or aerodynamics or aeronautical engineering or even building aircraft!, Nor do I have any idea if my calculations are correct, nor how close this airfoil represents the original airfoil designed for the Eros.  For all I know, an airfoil based on these ordinates might fall out of the sky, if it ever became airborne in the first place... With those realities firmly in mind, enjoy, modify, use to your heart's content...

Tony

Quoted from RedBird

Attached is a csv file (tab delimited) of ordinates based on NACA 4415 with max thickness reduced to 14% of chord length. If I have done this correctly that should make it a NACA 4414. However please note the following disclaimer:



Tony

That is one of the high lift airfoil. The only drawback: it has very high Reynold`d numbers (2 500 000- 4 500 000 depending of speed and other factors). For the Ison`s planes more than enough and will work better not exceeding Re=800 000-1000 000

Get one below with Re=810 000 high lift airfoil for slow aircraft and you will not be sorry

777:
Thanks for your insight. To be real candid, I'm not in a position to judge the aerodynamic plots you have graciously provided. As stated in my disclaimer, I have no knowledge of aerodynamics. I scaled to NACA 4414 only because it was identified as being the basis of the original Eros airfoil.

I am sure someone with genuine detailed understanding of airfoil characteristics and curves etc can make lots of cogent arguments for a particular choice. But I can't. I just was looking for a way to reasonably plot the airfoil originally intended so I could start working on my rib jig... I.e., I am not looking to "improve" the original design, just to accurately implement it.

Thanks again for your thoughts.

Tony

Quoted from RedBird

I am not looking to "improve" the original design, just to accurately implement it.

Thanks again for your thoughts.

Tony

Just take in account one thing- the Ison`s handly drawn airfoil has no any data at all. The Maxes are flying but no one knows how better or worse should it be.
The airfoil provided is the best one from TsAGI comes from 30-th for ragwing aircraft with speds not exceeding 170 km/h (100 mph roughly) and thousand and thousand airplanes flown and flying with one. For example An-2 (Antonov-2 biplane) with this airfoil  it`s wing lift with fully applied mechanisation is 3.5 (Cy=3.5)

:-/?
Bob

Quoted from flybob13

:-/?
Bob

Could you specify your question?

777,
I was just expressing my inability to comprehend all of this technical stuff. This is the best site I have found for builders and I REALLY appreciate everything that is discussed here. It's just that I'm kinda "low" tech. I think it's wonderful that there are people on this site that "know" this stuff and are willing to share. I personally just want to build and fly. My aerodynamic knowledge is basic at best, push the stick foward, the houses get bigger, pull the stick back, the houses get smaller. I was really just trying to be funny, you know, like when a dog hears a strange sound and cocks his head. Sorry, keep up the good work and info everybody, I'll go back and sit in the corner.  :)
Bob
P.S. I still haven't found the spell check.

Unless you keep pulling back----Then they get big again  REAL FAST!! Charlie

OK, for those who did not realize the polars of the P-II airfoil. Look at the curve Cy (alpha) where one crossing Cx (at Cy alpha) and project this cross point to angle of attack (some 25 degrees) than read data what is lift  coefficient at this point. This point shows non stall regime for this angle of attack. Could anybody say something similar or KNOWN about original Max`s airfoil? This airfoil is the result of TsAGI`s  work with their scientiests, equipment, wind tunels and so on.

Bob - I understood your  :-/ post, better than I understood 777's comments and graphs...  777 probably knows his stuff pretty well, at least it appears that way to an uninformed novice like myself... However, it is human nature, at least for some of us, to utilize and put confidence in information we feel we can comprehend, more than that which is just presented as fact, even by an authority or expert.  I suspect there is a wealth of insight in the graphs 777 posted. But for those of us who have not studied aerodynamics, interpretation of that information might be enhanced if it were supplemented by a cogent explanation.  Of course, I suspect there are some builders here for whom the graphs made perfect sense at first glance. However, I assure you, you were not the only one who didn't "get it." (at least there are two of us ;-)...)

777 - I guess my point is, that depending on your objective, and  your target audience, you might want to assume a little less technical training/knowledge of some of us. It sounds like you have some good insight to offer. But remember, some of us chose to build a 'max design because of its apparent simplicity, and its reputation as a reasonably stable, dependable homebuilt design. I do think most of us are open to learning and improving our understanding of most issues related to the process... But some us will require a little edification along the way :)...

just my opinion though. Thanks for your insights. - Tony

I have been doing this airfoil stuff for 60 years, believe me, 777 has a good point but MY openion is us mortals cant tell the difference in the speed regime of the maxi's.  flat bottom, curved top not to pointie of leading edge and the wingy will produce lift at an angle of attack. even if it is flat on top it will lift at an angle of attack. the science part will predict the exact performance but most any foil will make lift.  Also wings make drag. too much drag is bad.

Thanks Bear!... I follow :-).

Quoted from RedBird

   I suspect there is a wealth of insight in the graphs 777 posted. But for those of us who have not studied aerodynamics, interpretation of that information might be enhanced if it were supplemented by a cogent explanation.

777 - I guess my point is, that depending on your objective, and  your target audience, you might want to assume a little less technical training/knowledge of some of us. It sounds like you have some good insight to offer. But remember, some of us chose to build a 'max design because of its apparent simplicity, and its reputation as a reasonably stable, dependable homebuilt design. I do think most of us are open to learning and improving our understanding of most issues related to the process... But some us will require a little edification along the way :)...

just my opinion though. Thanks for your insights. - Tony

ОК, Tony :), let`s talk about one more issue on the P-II graphs.

You may ask people who flown Maxes, they will tell you one thing- all of them have to keep forward pressure on the stick immedeately after take off so that not allow aircraft nose went up too much, not loose speed not spin.... down at last. Did one of them ask why this happening? Because no one knows how centre of pressue of original airfoil migrates depending of angle of attack.

I do not say a word about good o worse specs for original airfoil. Anyway it works and works pretty  fine.... Mr. Ison did a perfect design work and his planes a best around all similar (otherwise I would be in another BBS ;D).
But!!!!!!!!!!!!!! They could be a bit better :). This will not harm not to planes not to Mr. Ison`s reputation (last one without questions at all).

Look at the polars. You may see the curves Mz- that is a moments (not about time ;D, but about forces). Mz does not change it`s value from zero to above angle of attack- that means centre of pressure for this airfoil remans constant and not migrates depending of how up goes aircraft nose. There are no forces to pull nose up. That means you need to be less cousious about possibility loose climb speed and do not need keep under control forward pressure on the stick. That is all- you have less chances to spin

777 -
I think we are discussing two different issues here. Not a single post in this thread has questioned your opinion about the flying qualities of the P-II. In fact, the person who has years of experience with airfoils agrees with your points. However, we don't all speak your language (not country  ;D, but technical). Speaking for myself, your last post was the most helpful because you offered a reasonably cogent explanation of one way the two airfoils differ. I.e. a static center of pressure, regardless of angle of attack. Based on your explanation, even I get it ;-). So, thank you.

Again, I am not arguing your technical opinion. (after all, less chance to spin might be considered a good thing by some ;-)..) I am only suggesting that some of us can appreciate your insight more when it is offered in a format and with terms that are at least partially familiar to us.  

Maybe others here already know, but I am curious, what model minimax are you building, or already flying? And, are you building/flying with wings based on the P-II airfoil that you are enamored with?

Tony

Uuuuuuuuuuhhhhhhhhhhhhhh, OK.  ~~~~~~~~~~~~~~~
                                                       ~~~~~~~~
                                                          ~~~~
                                                              :-/ ?
These lines repersent a swift movement of air over my head. I love it!
Bob
                                                
                                                
                                                    

~~~ :B~~~~~

these lines represent swift air moving through my own head... some have suggested to me there is not a lot inside to slow it down or cause turbulence... but no need to reply based on evidence gathered on this forum folks ;-)...

Hi Bob;
Do a search for ieSpell. I asked the same question many months ago and someone told me how to get this program. it is free and works great. It works with anything. Either r click or you can find it in the tool menu (after installation). You might try the Internet with a search of ieSpell. I wish I could tell you how to get it.
Fly safe, Bob Hoskins

777 brings back a memory I had not thought about in some long time. Back in the day when airplanes were just starting to become popular. designers tried to find ways to go faster. removing one wing helped. removing all those flying and drag wires helped more. BUT, wings started to come off. they did not brake but twisted off the fuselage.  the torgue due to the lift center shifting caused unexpected loads. the naca later nasa began a long series of wind tunnel testing to produce a series of airfoils the 230XX shaped that tried to avoid the pressure shift with airspeed.  They in fact succeded and things like DC_3's became common place.  the only drawback to these foils is the bad manners at the stall. The brake can be sudden and unpredicted.

Quoted from RedBird

777 -
what model minimax are you building, or already flying? And, are you building/flying with wings based on the P-II airfoil that you are enamored with?

Tony

No flying now, Tony (everything in the past so far... from rags to jets). Just designing and building ...... Chick-Max (she must look like a chick, isn`t it?)... and another interesting thing...  if the others will be agree to this name ;D ;D ;D.... and defintely with P-II airfoil

Back to the Airfoils again

777 your original Design looks a little bit like the Proto of the Rans Stinger or here in Europe more known C22 and X-AIR!

Why did you chose the over the nose engine configuration and not the config where an engine belongs to, the nose and not the forehead? ;-)
Just my personal idea, same rounded design but engine in the nose and cantilever wing and a Taildragger, yeahaaa.....!

Bst rgds

Erkki

The next time you fly your minimax watch how the fabric balloons up between the wing ribs. You can actually see the top of the wing distort the airfoil as you change air speed and angle of attack. Is this thing we call flight grand or what.  ;D

Here is P-II 16% (the best thickness for this airfoil) done for Minimax/Himax 54 inch chord in natural size,  could be printed on the B0 paper format 1400mm x 1000mm . In addition for alluminium airbike drawings (posted above in a thread within a link) the same airfoil with chord 1300 mm

Yup, looks like a cousin to the X-air. If it flys as good as the xair it'll be a nice bird. Can't wait to see it fly!



M3

Quoted from MiniMaxMan

Yup, looks like a cousin to the X-air.



M3

I am not sure about cousin. There is just a concept widely presented around the world. Actually all the aircraft are cousins :)

I havent been following this thread closely however try this site .....theres alot there.  

http://www.ae.uiuc.edu/m-selig/ads/coord_database.html#N

and Naca 4415 is  below....just follow the X and Y co-ordinates...this site has alot of aerofoils to keep you guys busy
1.00000     0.00000
0.99893     0.00039
0.99572     0.00156
0.99039     0.00349
0.98296     0.00610
0.97347     0.00932
0.96194     0.01303
0.94844     0.01716
0.93301     0.02166
0.91573     0.02652
0.89668     0.03171
0.87592     0.03717
0.85355     0.04283
0.82967     0.04863
0.80438     0.05453
0.77779     0.06048
0.75000     0.06642
0.72114     0.07227
0.69134     0.07795
0.66072     0.08341
0.62941     0.08858
0.59755     0.09341
0.56526     0.09785
0.53270     0.10185
0.50000     0.10538
0.46730     0.10837
0.43474     0.11076
0.40245     0.11248
0.37059     0.11345
0.33928     0.11361
0.30866     0.11294
0.27886     0.11141
0.25000     0.10903
0.22221     0.10584
0.19562     0.10190
0.17033     0.09726
0.14645     0.09195
0.12408     0.08607
0.10332     0.07970
0.08427     0.07283
0.06699     0.06541
0.05156     0.05753
0.03806     0.04937
0.02653     0.04118
0.01704     0.03303
0.00961     0.02489
0.00428     0.01654
0.00107     0.00825
0.00000     0.00075
0.00107     -0.00566
0.00428     -0.01102
0.00961     -0.01590
0.01704     -0.02061
0.02653     -0.02502
0.03806     -0.02915
0.05156     -0.03281
0.06699     -0.03582
0.08427     -0.03817
0.10332     -0.03991
0.12408     -0.04106
0.14645     -0.04166
0.17033     -0.04177
0.19562     -0.04147
0.22221     -0.04078
0.25000     -0.03974
0.27886     -0.03845
0.30866     -0.03700
0.33928     -0.03547
0.37059     -0.03390
0.40245     -0.03229
0.43474     -0.03063
0.46730     -0.02891
0.50000     -0.02713
0.53270     -0.02529
0.56526     -0.02340
0.59755     -0.02149
0.62941     -0.01958
0.66072     -0.01772
0.69134     -0.01596
0.72114     -0.01430
0.75000     -0.01277
0.77779     -0.01136
0.80438     -0.01006
0.82967     -0.00886
0.85355     -0.00775
0.87592     -0.00674
0.89668     -0.00583
0.91573     -0.00502
0.93301     -0.00431
0.94844     -0.00364
0.96194     -0.00297
0.97347     -0.00227
0.98296     -0.00156
0.99039     -0.00092
0.99572     -0.00042
0.99893     -0.00011
1.00000     0.00000

regards Arthur

Thanks Arthur, but I think I'll pass. If I can live to be old enough maybe I'll have time to creat my own design. "NOT" !!!! LOL  ;D
But seriously, that's a lot of info you got there.
Bob

I did a project when I was in an aviation class in high school at a skills center that was pretty fun.  We got to pick out coordinates out of a book and us a drafting board to draw the airfoil using drafting tools.  Then we photo copied the drawing and reduced it from a 12" chord to a 6 inch chord.  Then we made two aluminum sheetmetal templates using the photo copy for a pattern.  The two templates were then glued to a block of pink foam insulation and we used a hot wire cutter to make a 6" wide "wing" section of our airfoil.  We had a simple wind tunnel about 4 feet long and maybe 18" in diameter.  The foam wing section was mounted in the wind tunnel and it had a way to measure the lift using a simple digital scale that read out in grams.  We then "flew" the airfoil in the wind tunnel at different angles of attack and recorded the results.  All in high school!