I had a 72" CAP21 a few years ago. The biggest problem on these is weight! Keep it light. Other than that, very sweet flying aircraft.

The servos need to be fairly strong. I used Futaba S128's on all surfaces. The rudder was pull-pull and the elevators were driven by a split pushrod. A 6V flight pack was used. The nose moment is fairly short so be careful of the CG. An OS 1.08 pulled it good.

Safe Flying!