Ok, so it begs the question... Do you really want a hovering, unlimited vertical Eindekker, or do you want an aerobatic Eindekker, or do you want a semi scale Eindekker?? The second two could be accomplished with a Ryobi. A 3D Eindekker with a Ryobi would be extremely difficult. The power to weight ratio just isn't there for that particular engine. "Hovering" with a wing warping airplane would be a trick too. Hovering requires large and effective control surfaces in the prop blast to work.

I believe a nicely aerobatic Eindekker could be made with a Ryobi if it had about a 74 to 80" wing span, and was built fairly light. My brother has a 14 lb. 80" span Ryobi powered Ryan's Rebel, and it does all normal aerobatics just fine, but certainly no 3D.

AV8TOR