PDA

View Full Version : Airfoil Choices



challenger_i
09-15-2009, 10:57 PM
Question:

What would be the implications, both good and bad, of changing the airfoilf from the USA 35 to the NACA 23012?

Would it be beneficial, to use the 23012 on a new-build project?

Curley
09-16-2009, 07:09 PM
Before you make any decision on an airfoil change, I suggest you get a book called "GA Airfoils by Harry Riblett". I got mine from the EAA in Oshkosh and it has details of 35B plus many other similar airfoils and while it tends to be a little pedantic in places, is the easiest of any similar books to understand.

I will be using Riblett's GA30-613.5 on my "experimental" project as I want a wing that will give the highest cruise speed for HP and good low speed handling. Time will tell if it's the right decision but it's not hard to change if I am wrong. (Yeah I know - rip off all that lovely new fabric, replace the ribs, etc and recover! ;))

Geoff Newcombe
09-16-2009, 10:29 PM
" ..... on a new-build project?"

By that do you mean building a non-certificated aircraft, or a restoration and build up of a short wing?

challenger_i
09-16-2009, 11:02 PM
Ummmnnnn.... Well, I did post this in the "Experimental Shortwings" section...

Yes'r, this idea is for an experimental build, such as a Wagabond, and the like. It would be WAY too much paper work, and hassle, to do it to a certificated bird.

So, my question stands: what would the effects be, both pro, and con, for using the NACA 23012, rather than the USA 35?


" ..... on a new-build project?"

By that do you mean building a non-certificated aircraft, or a restoration and build up of a short wing?

challenger_i
09-16-2009, 11:07 PM
I'd love to see the profile of that airfoil section. Sound's interesting.

I was basing my idea on the difference in performance, between the J-3 (USA 35), and the Taylorcraft (23012). With the same chord, the same span,
and the same power, the T-Cart outperforms the J-3. I know there is more to the comparison, than just the airfoil, but it does play a large part.

The 23000 series is still a good performing section, as it is the one used on the majority of the Van's designs.

Thoughts? Hints? Suggestions?




Before you make any decision on an airfoil change, I suggest you get a book called "GA Airfoils by Harry Riblett". I got mine from the EAA in Oshkosh and it has details of 35B plus many other similar airfoils and while it tends to be a little pedantic in places, is the easiest of any similar books to understand.

I will be using Riblett's GA30-613.5 on my "experimental" project as I want a wing that will give the highest cruise speed for HP and good low speed handling. Time will tell if it's the right decision but it's not hard to change if I am wrong. (Yeah I know - rip off all that lovely new fabric, replace the ribs, etc and recover! ;))

d.grimm
09-23-2009, 11:25 AM
A old friend (deceased) put a clipped T-Craft wing on his outlaw Vagabond. Said it flew nice but he didn't get the angle of incidence just right. Didn't see any big improvements high or slow speed.
Dave

challenger_i
09-23-2009, 09:18 PM
Hmmmmnnnn..... Ok, the inaccurate incidence would cause the lack of change. Ya'll are going to make me have to build a Vag, and two sets of wings, aren't you?! :p

Let's see here: Beefed up Wagabond, O-290D2, 74x56 screw, 23012 airfoil...
This could be interesting.

challenger_i
09-23-2009, 10:50 PM
By golly, I found a lead!

There is a bird, called the Myers PM-1 Special. It is a very modified J-3, and has a clipped Taylorcraft wing (22ft 7 in.). Definitely qualifies as a Short Wing Piper!

http://www.airventuremuseum.org/collection/aircraft/Myers%20PM-1%20Special.asp#TopOfPage