I'm not an engineer, but I used to be a professional pilot. I've got over 4000 hours PIC and an Airline Transport Pilot rating. I guaduated from Embry-Riddle Aeronautical University with a degree in Professional Aeronautics. I'm also an avid RC flying fan.

So, *maybe* I'm qualified to talk about this. The first question I need to ask is why Fowler? Is there a real need for the RC plane to have an increased surface area when the flap is in use?

Generally, I'd go with a simple flap design (probably split) for RC aircraft. It avoids the unneccesary mechanics of the more complicated Fowler design while still giving the aircraft significant perfomance changes in drag and lift.