I have plans for a 1/4 Scale Kitten designed by Emil Agosta.
It has a 90" wing and 1080 sq. in. area.
The plans claim a weight of 7.5 Lbs. and recomends a .40 2c glow.

Anyone have one of these birdies?

I was hoping to put my first Ryobi on a nice leisurely high wing like a kitten, but according to those specs, I'd have to enlarge the plans by what, 30% or more?

That would be nearly a 10 ft. wing! [X(]

I don't have a problem re-engineering to that size, but my goodness, what a space hog that will be in my shed(mini-barn) and on the flight line.

So, the real question for you "Experienced" folks is this: would the Ryobi be a good fit with a 30% enlargement? How about 25%?

Thanks,
Tom

I don't think you need to go to 30% or even 25% enlargement. 20% will give you an 8 Ft, wing and 1555 sq. in. area, and if you can keep the weight down to 12 or 14 lbs or so, it will float like a butterfly. Just doing the cube function on the 20% increase on 7.5 lbs gives 13 pounds. and the Ryobi weighs about 4 pounds in itself so a 12 to 14 pound target seems reasonable. When you scale up the plans go for pine or spruce spars with shear webs, good strong struts, braced tail surfaces and stout landing gear.

My 1/4 scale Cub is very close to the size of your 20% enlargement, and flies fine with a 28cc Ryobi that turns a 18X6 at 7000 rpm max on a good day. And the Cub weighs 17 pounds!

Allan

Ooops, 20% enlargement gives 108" span, which is 9', not the 8' typo as per my previous post. Area is still 1555 sq in and the rest is OK (?!).