I guess you could increase the aspect ratio to what you think it ought to be. I don't see little airplanes (or classic airplanes, which were powered by wimpy engines) with appreciably more aspect ratio than modern big ones, but the little or old ones often don't have as much speed regulation from engines, so a high aspect ratio would tend to make them more prone to windup. I would reckon that the optimal aspect ratio of an electric stunter is greater than that of an Otto engine powered stunter, both because the electric can regulate speed better and because its fuel weighs more.
I just thought of another aspect of aspect ratio: to wit, higher aspect ratios are more sensitive to turbulence because they have higher lift curve slopes (hence my enthusiasm for super-low aspect ratio canard surfaces, but that's another story). Maybe your fancy wing tips can give you the requisite efficiency with less turbulence sensitivity. Was David Fitz onto something?
I suppose I should have been clearer, but I've just been checking in and out of this conversation amid a lot of other distractions. I certainly agree about aspect-ratio effects and, to address an earlier comment, I wouldn't take these considerations out of the context of the entire design in their
application. My posting of wing configuration effects was not meant to ask anyone to ignore good design practices. I was just isolating some specific trends.
So my last post was directed only at the statement about induced drag. All else being equal, I think lowering induced drag can be beneficial, while lowering parasite drag is generally not helpful at all in stunt models. I never meant to indicate that tip efficiency should dictate overall design. What you say about t.e. discontinuities - flap, tabs, etc. - also seems quite correct, and this issue sometimes even favors the ellipticasl wings, which also have the furthest inboard a.c of all commonly proportioned (i.e. not pointed) wings. Overall, it seems that the swept tips on tapered wings may have the lift efficiency advantage, but that's obviously not everything either. As you said, not only are high-aspect-ratio wings more sensitive to lateral disturbances, but their efficiency in lift (higher lift-slope curve) causes them to jump more when encountering an airspeed change; that fits my limited experience. I did once post though how within some limits one can diminish lateral high-aspect-ratio effects with increased taper; there's probably a little room to play with there, at least on larger models. My 56" , high-A/R, tapered model with swept tips flew a bit better than I had expected.
As for canards, I know you were addressing only aspect ratio, and I see why lower aspect ratio there would probably move the total a.c. back and reduce their loading, while decreasing the spanwise wake effects. FWIW though, I see them as advatageous only in 3-surface aircraft and not as a foreplane "tail" for "monoplanes" without aft tails too. This is because of wake interference and inability to use the main wing's total lift, due to c.g. placement relative to the aircraft's total aero center and static margin requirements. There's some good quantitative stuff out there on this topic, including some research and theory by Stanford's Illan Kroo. I know I've posted it more than once, but the biggest thing I wrote on that here on stunthang
ar was lost with several others in a crash a year or so ago. Anyway, I think that a model with large main wing (or bipe), having fore and aft tails, like the Adamison design, is a reasonable stunt idea, but the aft area is the stabilizing area.
I'm sorry if I addressed too many topics - away from wing tips - especially since I have to be elsewhere much of the time during the next couple weeks. So, if there's need for further participation here, please be patient. I'll try to check in.
P.S. I got that red "warning" that another post has appeared, but time says I need to just post this now and get out.
SK