Hello-

I am trying to install both my rudder and elevator control horns on my second Avistar. The manual says to place the rudder control horn one inch above my hinged horizontal stabilizer. Placing the control horn at the recommended location creates a significant downward bend in my pushrod wire. Is it okay to place the control horn higher up on the rudder to create a straight pushrod wire. I installed the pushrod wires first just to see where they would lineup on the rudder.

Any suggestions would be greatly appreciated.

Thanks!
Bjfrankl

Yes you can place the control horn anywhere along the hinge line. In fact it is a good thing to place the horn so that the pushrod moves as freely and smoothly as possible. The figure they gave you was probably just an approximation. You could also just put a slight 'zig-zag' bend in the end of the pushrod so that the end lines up with the control horn. Either way will work.

Yeah, this is just a suggestion. As stated, put it where it will be free from any binds. Set the linkage so that it too will not bind, using metal rods with a bit of a Z bent to align it so that the linkage moves straight is the best idea. The main point is to get the rudder to move right and left freely with no binds.

CGr.

Sure. The straighter the control rod run is, the better your control will be.

As stated above the push rod needs to be in line with the control horn......just make sure there is enough aircraft structure to support the control horn at the new location

Besides those advices, the pushrod movement should as perpendicular to the hinge line as possible.
If not, a ball linkage may be needed.
In other words, try to avoid any twisting or bending stress between the clevis and the horn, since the first one could break after a while.

Any pictures?

To help position the horn, apply a strip of double sided tape to the horn base and then place it on the rudder/elevator. This will allow you to fit the pushrod and make any adjustments in the position of the horn without ruining the rudder by drilling holes in it. When you are satisfied with the posioning, drill the mounting holes, remove the horn and take off the tape. You can fasten the horn with the screws and it will be exactly in the right place.

Wedge

It's also very common to put a bend in the pushrod about 1" past the exit

Thanks for all the responses! This will be the second time that I have installed control horns, and I want to be sure that I install them correctly.

Bjfrankl