Hello All,

I have just finished building and have flown a new Extra 300S, 60 size. I was very satisfied with the way the plane (ARF) was assembled and found no building problems. On the maiden flight it took only a couple of trim bumps to have the plane flying hands off. BUT, there is one problem I cannot figure out. The plane tends to wiggle side-to-side like the rudder is loose. Not bad enough to loose control but it is real aggrarvating. I have checked for loose/sloppy pushrods or servos. The distance at hinge lines is very, very small and should not be a factor especially since the speed of the plane does not seem to be a factor. Anybody have an idea of what is going on here?

Sonnytex

When it happens?

The airplane is side slipping? Oscillating back and forth in the yaw axis?.....
On the ground, with the engine running try to do a range check and see if you can duplicate the problem.....
Are you using any servo extensions?
If you can't find the problem after trying servo, extension, or perhaps a reciever...try your non/off switch.....
Look outside the airplane, engine mount tight, double check to see if your hinges are tight no side to side play.....
My daughter flies a 300 with no issues so I doubt it has anything to do with the design of the airframe...
You can also try and seal the hinge line and see if that fixes the issue.
Let us know what you find

I've heard of a "wiggle" like you describe on Corsairs, but never on an Extra. Make sure your control horns and pushrods are as rigid as possible, reinforce or replace any that look suspect. If it is an aerodynamic anomale, try changing to a different prop (higher or lower pitch) to see if that helps.

Sounds like your rudder servo is not centering correctly. As mentioned, check it out on the ground without the tailwheel touching the ground. It could be the servo itself or an extension, if you're using one. Keep us posted!

Thanks guys for the suggestions - most of them I have checked out but a couple are worth reinvestigating. I'll let you know what I find.

Sonnnytex

How fast is the wiggle? Fast would indicate something wrong structurally or aerodynamically, while slow would indicate a control issue.