Gentlemen, I'm in the process of scratch building a Liberty Sport bi-plane. I'd like to experiment and use a pull-pull system for rudder / elevator - never done that! The rudder is pretty straight forward but how would the rigging go for the elevator? Would not the pull-pull control extend over the, "fixed", fuselage portion of the elevator. Comments? Suggestions?

Which plans are you using?
I'm using plans from M.A.N. Roger Stern.
About the only way to use pull-pull for the elevator would be the way you suggest unless you could find enough room in the tail to put a couple of horns.

Steve

NavyE6FE - The plans are from a commercial SIG kit. Probably 10-15 years old. Neat airplane - 40 size.

Mine are for a 7'+ WS. On a .40 size you might be able to tie the two elevator halves together and use one pull-pull horn to run them both. or is this the way the plans show? Good Luck

Steve

NavyE6FE - the plans are vague as far as elevator / rudder and throttle control goes - they seem to be at your descretion. The plans used bellcranks in the lower wing for aileron though. Can't say as I care for this scheme and intend on using (2) mini-servos for aileron. I'd even like to use a cable for throttle control - my idea is to have a spring for keeping the carb barrel closed - a cable would tension the spring opening the carb - should make a no-slop control that is easy to get through the firewall. If I can, I might try a mini servo at the back for elevator - balance might be a concern on that. I'm using this aircraft to experiment with.