Splais,

You're talking two different things; a split elevator pushrod, where you have two independently-hinged elevator halves, each driven by one side of a split pushrod, is an entirely different animal from a push-pull or pull-pull rudder (or elevator) set-up.

Not sure what you mean by "extra servo". I have one servo driving the rudder bellcrank and one servo driving the elevator pushrod. The rudder servo is offset because when using a split elevator pushrod it MUST be centered in the fuselage; otherwise, as it moves it will move one elevator half more than the other. You can see the problem that would cause.

It is possible to remove the differential in an offset pushrod by bending one side, but that would take quite a bit of trial-and-error, and we know that the less bends in a wire pushrod, the better.

Anyway, the use of a bellcrank allows the rudder servo to be offset so the elevator servo can be centered, while keeping the bellcrank for the rudder centered as well. Ya just have to think in three dimensions...<BG>

Volfy, I don't doubt you for a minute. But I'm drawing on my experiences with helicopter linkages and solid pushrod/ball link set-ups. With those, you had BETTER have a perfect parallelogram, or binding will result. I guess the short distances involved do not allow the radii differential to erase itself. Interesting...

Steve