[juice90]

hello all.. asking this question again, as the last time i asked it, there was no response.

I have an old nosen citabria kit, but the original was a 3 channel with no ailerons, and a flat bottom, clark Y airfoil. I want to change the airfoil on the wings and wondering what kinda airfoil to use. A semi symetrical or a fully semetrical.

I am looking for some ideas or an actual airfoil to use on this plane. I would like it to be able to perform some scale maneauvers, and fly decently.And have ailerons.

Has anybody done this, or built a larger sized citabria/ decatolon, and can tell me what airfoil was used or better yet, give me a copy of the airfoil.

[kcaldwel]

The real Citabria used a NACA 4412 and the real Decathlon used a NACA 1412. Those are the same thickness forms, but the 4412 has 4% camber, and the 1412 has 1%, so it is far more symmetrical.

A pretty good list of airfoils of real airplanes:

http://www.ae.uiuc.edu/m-selig/ads/aircraft.html

GIFs and coordinates for these and most other airfoils can be found here:

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

Both these airfoils work quite well at lower Reynolds numbers, and with a 1/4 scale model would give pretty good scale like performance.

Of course, more modern model airfiols could perform better. I could dig out my Selig/Donovan data to pick one for you if you are interested in the ultimate aerobatic performance. The real airfoils would likely be great on a 1/4 scale, and scale too!

Kevin Caldwell

PS: here is good description of both aircraft in detail:

http://mail.westmont.edu/pipermail/a...er/044757.html

[igor_throw_the_switch]

Originally Posted by kcaldwel

The real Citabria used a NACA 4412 and the real Decathlon used a NACA 1412. Those are the same thickness forms, but the 4412 has 4% camber, and the 1412 has 1%, so it is far more symmetrical.

Split the difference and go with a NACA 2412. I used one on a foamy Agwagon and I was quite happy with it

Brad

[scaleguy]

Brad,

A foamy Agwagon? Do tell!