You won't need a .91 in the Contender. I'm swinging a 13 x 8 on an OS FS-70 4-stroke and I can take off of grass at 1/3 throttle.

Wish I'd set the engine on it's ear with the exhaust down below and not built the wing tips bent up. Foxflyr's is a much sleeker looking plane than my Frankenstein. The optional tip build is/was supposed to prevent a Dutch Roll (a yaw and sudden snap roll in the opposite direction of an intended roll). One in our club has the regular tips and shows no tendency to do that.



I added 30% more rudder area and made the scoop functional with a 1/4" x 3/4" half cylindrical opening. Doesn't really need the apron flap but it is fun to play with. Nice, rugged model.

(Say, how do you add images so they are thumbnails that can be enlarged as needed instead of poster sized to begin with - sorry.)