RE: Balsa USA Fokker E . III Eindecker build
My buddy and I had 3 Balsa USA Eindeckers, one giant, covered with Solartex and finished as an Austrian A-3 , one small, finished in red 21st century, and a second small one, bashed into a Morane-Saulnier Type N (Fokker copied the wing of an earlier Morane).
We flew the big A-3 with an OS 1.08 2-stroke, but sold it to a man who used an OS .91 4-stroke. You don't need full power with either engine.
If you plan to fly nice and slow at a scale speed, the plane will be fine as designed. If you plan to go faster and do acro, it has some limitations. With the incidence and flat bottom airfoil, it tends to climb like a trainer at full power. On the Morane version, during construction, we raised the TE of the wing 3/16 inch to counter the climb. This worked somewhat, but wasn't completely satisfactory. It really needs a symmetrical airfoil for good acro performance. The plane has good moments and a good sized tail, both non-scale, so it could be a fairly good acro plane and still have the scale looks.
We moved the ailerons in one bay and lengthened them. They are fairly small. You can see on the Morane where they are located and the size. They are non-scale, anyway, as the full scale used wing warping.
The Morane mod is covered with antique Solartex cloth and painted with clear polyurethane. We also added the scale landing gear and flying wires.
Either size is a good flying, semi-trainer type plane. It is very easy to land, but will tip on a wing tip in a crosswind taxi.