Keep the original wing section or modify it??
 

Hi folks, I'm here in a big dilema so I'm turning to you aerodynamic experts for an advice.
I've decided to build 1/3scale Bob Nelitz Taylorcraft. Now, when I'm looking at the plans and measuring incidents the stab looks like is zero degrees, wing section is about 2 to 3 degrees plus and the engine is zero. I know a few guys built this one with putting everything to zero and using symetrical airfoil rather than the original which is sort of semisymetrical. Apparently this was done for more aerobatic (neutral) feel. Can somebody tell me how this actualy works? Because that's the feel I would like to have on this plane so when I invert it I would like to be able to fly this plane nice and level rather than sort of nose high. I know a lot has to do with the CG but generaly speaking if I decide to use symetrical profile should I still keep those 2 - 3 degrees or can I put it to zero incidence? Thanks will appreciate your comments.

RE: Keep the original wing section or modify it??
 

The T-craft used a 230XX airfoil (XX refers to the thickness in percent). This airfoil has been the workhorse in the industry almost forever. You would find it on the DC-3, most precip Beeches, Van's RV-3, 4, and 6 homebuilts and many others. It will fly inverted fine, and be more scale doing it. Since a model is so light, you might want to lower the incidence, because the full scale work the incidence based on the wing loading and cruise speed.

RE: Keep the original wing section or modify it??
 

Thanks for the reply, sounds like I can stick with the original profile. Hmm.. just don't know why most people I talked through the net about this plane, most of them modified wings (don't know about the section) but in general whole design as it appears quite overbuild, using a lot of birch, spruce and ply. One guy I talked to apparently zeroed incidents and used profile from his Edge 540. The thruth is, I don't really know how his plane flies. I want to make nice aerobatic machine that will have characteristic of a more modern aerobat. My qestion is, can this be achieved with plane like Taylorcraft?

RE: Keep the original wing section or modify it??
 

It sounds more like you're trying to make a sport pattern sort of model that happens to look like a Taylorcraft. For that sort of application I would suggest that your idea of symetrical airfoil and all 0-0-0 setup will be better for you as long as you're happy flying that sort of very neutral handling model and take the time to set up the appropriate neutral sort of CG.

You'll end up with a high wing model that still has some of the charactaristics that go along with that sort of layout. It won't be scale or fly like the scale prototype did but it sounds like this is more what you want than a scale sort of performance and handling.

Both options are valid but the scale versus "looks like" options will produce two very different handling models. It's up to you to choose which you want.

RE: Keep the original wing section or modify it??
 

Maybe I should be more specific. Last year I saw this plane at Joe Nall doing some very low knife edge passes I think it belonged to Warren Thomas but I'm not sure.
This model looked and flew awesome. All I know it had a lot of modifications done to it. Now,that's the model I want to build. Maybe this helps. I wish I could contact the guy. Here is the pic of one of those KE passes.