What effect does it have on flight when the control horn is not on the hinge line?

What happens when one side IS on the hinge line and the other side is not?

When the control horns holes are not on the hinge line your throws will be unequal. Depending if the are behind or ahead will dictate which direction will have more/less travel. If they are different on both sides that will just make it harder to get things equal.

In both cases, depending on the type of horn and the plane, this can also throw off mechanical advantage which is very important to help reducing flutter.

Hello CG,
as Bill said this will affect throws: I suggest to you to fix it (in case you have this problem) working on the linkages stuff and NOT working with radio programming.

I say this because not only is best to adjust things mechanically if we know the problem, but also (and more importantly) you almost can't get equal throws working on radio programming if you have a unsound mechanical base.

On this topic very good infos can be found on Troy's article at central hobbies site, click "Informational" on left menu. You will find a serveral part well written article on control linkages.

The simplest way to get symmetric throws is with the horn pickoffs exactly on the hinge line as you guys say, but it's NOT the only way. If you match the spacing on the control horn and servo arm and offset the pickoff points by the same angle as the offset in the control horn vs hinge line, everything matches perfectly. It's a pain in the tail to do............. but it works. I did it on my Excelleron rudder, just to keep from buying an extra $25 in parts and throwing all but the extended horns away.
Gordie