Someone11-RCU

My Feedback: (2)

Which airfoil design is the best for an aerobatic/sport glow airplane? It has a low-wing design and a 60in. wing span. Which airfoil should I use in Stefano Duranti's Profili 1.2? (I downloaded this program, and don't know which one to choose out of the 1800 choices.)


Thanks-Brian

erwinf

You can try this:

S8035 for RC aerobatic 14% thick

I haven't personally tried it but the name says it's for RC aerobatic.

Hope this helps.

wled123

Don't waste your time on those fancy airfoils. Without going into airfoil theory, L/D curves and Reynolds numbers, go for a standard symmetrical airfoil with about a 12% to 15% thickness ratio, hence a NACA 0012 thru NACA 0015. Easy to cut a foam core or build up from ribs/caps. If you are looking for something easy to stall (i.e. snap roll), go with the thinner airfoil and sharpen the leading edge, you pay for it with higher stall speeds. For good landing characteristics (i.e. GP Ultrasports), go with the thicker airfoil and nice blunt/round leading edges. Something else that is typically done is go with a 12% at the root and 15% at the tip to prevent tip stalling. And then there is washout, but don't worry about that for now.

Someone11-RCU

My Feedback: (2)

Would a wing with 12% at the root, and 15% at the tip be good at aerbatics and getting around?

Someone11-RCU

My Feedback: (2)

This is my current airfoil. I decided on this one before this forum.

irishcarbomb

My Feedback: (4)

Looks like the S8035 14% from Profili. i am using that on my aerobatic design. having Flying Foam cut my cores.

Someone11-RCU

My Feedback: (2)

Actually it is the first one; It is 12% JOUKOWSKI. I might go with the NACA 12% as root, and NACA 15% as tip, but I don't know if this would be good for sport flying and aerobatics.

MiL

what about Airfoils for funfly planes?

My first design/scratch project is a profile Funfly for a .25 bushing motor i've got. I just cut the ribs the other night, I used Profili to generate a NACA 0018 and then modified it by moving the "fat" part a little farther forward (which also made the LE a little more blunt).

Here's a pic that shows the shape of the fuse and the airfoil.

Someone11-RCU

My Feedback: (2)

Cool design!

can773

My Feedback: (1)

This is becoming mainstream on all high end pattern models, not that thick (11 root 12 tip or 12 root 13 tip). The general idea is for snap recovery, in order to help prevent over rotation after a violent snap. Use that with around a 33%-35% high point and you will be ok. Also running the ailerons and elevator straight off the end of the wing will improve snap performance.

Someone11-RCU

My Feedback: (2)

I desided to go with a NACA12% root, and NACA 15% tip. Here is what it looks like:

CrazyHerb-RCU-delete

My Feedback: (2)

Hey MiL!!
Got any dxf drawings of that profile?
I like the looks of that profile....BIG rudder!!

And I happen to just have a OS .25 sitting right here next to me!!

If you build it let us know how it goes!!

High Flights!!
CrazyHerb

MiL

I'll try to get a picture up pretty soon. When i drew it up, i didnt put much thought into mounting the radio components and stuff so it's been kind of slow building trying to figure out how to make it all work. And of course i've run into several small problems that i didn't think about untill i saw it in physical form in front of me. Hopefully will be flying before too long though. School has started and that will also slow me a little. I will definitely make a post when there is progress though.

I'm not too proud of my .dwg right now (it's kinda like my workshop, messy with a few different projects going on) but i guess i don't have to show off or anything so i'll go ahead and send you a copy if you'd like. Let me know your preferred email for recieving attachments.

Someone11-RCU

My Feedback: (2)

I'm not designing my plane for pattern flying though. I want my plane to be more aerobatic. With my selected wing thicknesses (12% root, 15% tip) would it still be adequate for aerboatics/sport? I'm fairly new to this hobby and dont know if there is a big difference between pattern and aerobatic wings, so I'm sorry if I'm making any of of frustrated by having to explain this stuff to a "newb" like me I appreciate all of your replys and views!

Thanks for your time - Brian

MiL

For CrazyHerb and anyone else intersted, here is a link to a thread in the Fun Fly forum where there is a picture of my plane and more info about it.

http://www.rcuniverse.com/showthread...374&forumid=21

MiLL

Mike James

You can get as technical as you want on this subject, but a general rule, when dicussing the symmetrical airfoils (above) with 9 to 15 percent thickness, is that if 14 percent is about typical for Pattern (i.e., an Eppler 168) then the slightly thicker sections you've selected will allow for slower flight and landings, due to their greater drag.

With a medium size sport plane, you won't see huge dramatic differences in these airfoils. (Of course, that's assuming your area and aspect ratio is also fairly typical.)

Someone11-RCU

My Feedback: (2)

Ok, I'll keep that in mind MikeJames0. Thanks for your reply!

KC10Chief

I'd have to agree with using a fully symmetrical airfoil like a NACA 0012 to 0015. If you're wanting to build a plane more like a fun fly plane, then I'd recommend the Eppler 473. I used it on the plane under my screen name. Flies great! You can't go wrong with a NACA airfoil either. Good luck! Matt

Someone11-RCU

My Feedback: (2)

My wing will have slight dihedral in it. It has a 3 degree dihedral. But to my question.... what do you mean by symmetrical? Is this just meaning wings the the same shape on top and bottom? (is it just like in math with symmetrical shapes and such?)

Thanks - brian

KC10Chief

Someone, a symmetrical airfoil is an airfoil that is the exact same shape on either side of the chord. Look at any NACA airfoil that starts with the numbers 00. I think anything between a NACA 0012 and a NACA 0015 would be good for your plane. The last two numbers are the airfoils thickness in relation to the length of the chord. For example, the height of a NACA 0015's thickness from top to bottom is 15% of the length of the airfoils chord (leading edge to trailing edge). The first two numbers have something to do with how far bach on the chord the highest point on the airfoil are. Not exactly sure how that works. With NACA, the first two numbers starting with 00 means that the airfoil is fully symmetrical. Good luck! Matt

Someone11-RCU

My Feedback: (2)

THANKS!