RE: Servo for 78" Chipmunk
Everyone is talking about +1000 sq.in. for a small gasser.
This is a slow flyer, over 1000sq. in. wing.
Push the nose back a bit to help balance it, reinforce the firewall and fly it scale.
A Toro weighs about 2 pounds ready to go.
It should lift the plane off the water pretty easily.
Why not?