One of the cardinal rules is to never fly the airplane "behind" you. Orientation is the big concern. It's hard enough when it is in front of you.
Here is a pic of my old Ultimate 10-300 bipe. It has about a 60" span, and is meant for a .60 c.i. two cycle glow engine, or a 1.20 c.i. four cycle glow engine. I checked weights on a variety of glow engines, and found an O.S. 1.08 c.i. two cycle that was quite a bit lighter than any 1.20 ci four cycle. Reasoning that it could carry the weight of the bigger 1.20 four cycle, there should be no reason I can't mount the 1.08 two cycle. It has about double the power...
This thing was (is) an absolute beast. Look at the sizes of the control surfaces. This thing can fly a full loop - knife-edged. In other words, on the side of the fuselage, using the rudder as the elevator. Its roll rate is about 1080 degrees per second - three full rolls per second, and it will do that while accelerating vertically.
Notice, though, the super long tail moment compared to the Pitts. And the sheer size of the tail feathers. This was necessary in the old days, pre-gyro.
