I modified a Sig 4*40 to take a Selig 8036 (it might be listed as a S8036 or a SD8036). The airfoil is semi-symmetrical and was pretty quick (though I know that you aren't looking for speed). If you're not familiar with them, look up Dr. Michael Selig (University of Illinois, I think - but not sure). He developed these airfoils strictly for small aircraft use. I don't know if they were developed strictly for R/Cers or not (could have been developed for AUV's but I'm not sure). But they're optomized for the Reynolds numbers that we fly at.

Also, the 8036 is used by Top Flite for a couple of it's scale Gold Edition planes.

I intend to use it in a 1/4 scale Thompson racer with a 66" wing span that I'm drawing up, little by little.

Just a suggestion.

Bob