Thanks guys. Yeah I was pretty sure she'd fly if only I could get it off the ground. What I didn't expect was how nicely she flies.
Well the video
pretty much tells the story but here's a few thoughts...
The ground handling isn't good.
The guppy shaped fuselage with a big bulge right at the CG makes her rock back-n-forth causing a lot of friction. Although the shape looks good its does cause issues for sure. A wheel placed at the leading edge of the wing would have helped. I may fashion a custom dolly for her.
With the moderate wing-loading I expected her to fly pretty fast & she does get up & go when she wants too. I was afraid she might tend to overtake the tow plane like many slick modern scale sailplanes will do. The flaps were effective air-brakes though, pretty easy to control the speed on tow.
She flies like she's on rails, this is one of the most stable sailplanes I've flown. That's surprising considering the absurdly dinky fuselage & short-coupled tail. I expected her to be really pitch sensitive but she's not at all. The 40% expo on the elevator should be helping but it seems there's sufficient h-stab back there to make her natively stable. Turns are nice too. I have a fair amount of aileron differential programed & also mixed in some rudder (except when the aerotow release is closed) so she stays nice & coordinated. With the flaps also acting as ailerons the roll rate is pretty snappy for a sailplane. Again with the moderate wing-loading she carries a fair amount of energy which is great for aerobatics. Makes for some serious fun tossing her about the sky.
The big barn-door flaps were very effective. Although I've not tried a full flap, 45° nose down landing yet, I'm thinking she'll do that without picking up much speed. I have a 1/4" of crow programmed into the outboard ailerons to further slow things down but mainly to keep the wing-tips flying at low speeds. After all it was a tip-stall-o-doom that destroyed the original stock fuselage, I don't want a repeat performance. The inboard ailerons remain functional even when acting as flaps, so roll control remains crisp all the way down to stall speed. One of the easiest planes to land I've flown.
Before you laugh, if I can resist the urge to point the nose towards the ground & fly aerobatics, I think this daft little glider might actually thermal. Granted it'd probably need medium to strong lift but if I keep the airspeed up, the sink-rate isn't actually all that terrible. I know from flying some of my other heavier sailplanes, a high wing-loading doesn't necessarily mean she drops like a brick. Those do have nice long, high aspect wings with fancy airfoils though. We'll have to see.
We're talking an hour or two road trip at least if I want to hit the slopes. I think it'd be worth it though as there's little doubt where this silly Cub belongs. Fairly aerobatic, tough foam construction, big flaps for small landing areas, good wind penetration. She belongs on the slope.
So what I believe I have here is a "flat-land slope soarer". She's docile enough for some lazy thermaling (assuming there's enough lift) yet aerobatic enough to tare up the sky when she wants to. The aerotow capability means I don't have to shelf her until we hit the slope. I love the attention she gets too, definitely something you don't see every day. I wish she wasn't quite as beat up looking but at least I don't have to worry about scratching the paint. I could see myself building another one, perhaps a lot bigger, probably a lot lighter construction. I think that'd be something fun to take to the various scale aerotow events I attend. That's assuming they're okay with a "fantasy scale" glider in their midst. *grin*
A big thanks to the New Canaan Remote Control Society
for putting up with my silliness. You guys are the best. And also for those that contributed advice here on the forums. Well time to move on to the next project. Stay tuned for more "adventures in radio control"...