The following is what Dee Rice sent me in an email.. Am sure he doesn't mind me broadcasting it..
The 576/526 story began last year when I called my friend and noted model designer, Pat Johnston, and told him that I wanted a close to scale Ringmaster in the upper 500 square inch range. I wanted it with a modern airfoil, flaps, and other modifications that would give it the best possible flying characteristics so it would be capable of flying with modern expert level ships. I envisioned an airplane with small flaps, powerful airfoil and a large tail-volume-coefficient. My hope was that even with the shorter tail moment, we could make it aerodynamically similar to the French Berringer inspired stunt ships. I know, I know, that was a big hope.
Pat and I brain stormed for awhile and 10 days later I receive the first set of Ringmaster 576 plans in the mail and it looked great. We talked again and made a few more structural and aerodynamic changes.
With a powerful lifting airfoil and inherent light weight, we knew the small flaps would be just right. Also, due to the relatively large area of the original stab/elevator of the S-1, the exact scaled up areas of the stab/elevator with only an inch longer aft fuselage; we were able to get the tail leverage (tail-volume-coefficient) in the range we wanted.