I recommend a Great Planes Big Stik, (not the Giant Stik), and your Echo 21cc.  The Echo engines are light and powerful, and the Big Stik is the right size.  It has around 1000 square inches of wing and weighs around 10 lbs.  The 21cc Echo with a 10 or 11mm carb and a free breathing exhaust would fly it nicely.</p>

I didn't recommend the Giant Stik because of your parameters.  I have a Giant Stik and it flies great but I have my BME twin of 48cc on it.</p>

If you do one, assemble the plane, including the engine but without installing the elevator or rudder servos.  Then check the balance.  If needed, you can mount one or both of those servos in the tail to achieve balance.</p>

AV8TOR</p>

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