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Rudder/Elevator gap advice please

Just finished hanging my tail feathers on the fuse for the first time and am curious about the recommended rudder/elevator gap.

Plans on page 11-09 specify the LEFT gap (the one measured to the elevator trim tab trailing edge) as 3/4" minimum when the rudder is on its stop. I got lucky--mine came in at 13/16" as hung.
The plans are noticeably silent about the RIGHT SIDE clearance however. Presumably because it seems obvious that both sides should be governed by the same clearance limit, right...? My right side clearance to the trailing edge of the elevator measures 5/8" (1/8" less than the specified left side minimum).
Before I make an offset tab--shown on pg. 11-10 as optional if needed, I wanted seek your opinions.

1) Is 5/8" clearance inadequate on the right side?

2) Is it inadequate enough to justify the installation of an offset tab for the 1/8" gain in clearance?

3) Why such a seemingly large clearance limit? Are we expecting some kind of flexing to introduce possible rudder/elevator interference here?

4) What am I missing?

Thanks for your thoughts and experience on the issue.

Randy
 
There is a surprising amount of torsional flexibility on the rudder that only becomes a problem if it ever gets slammed against the stops by strong wind gusts.

The inertia of the counterweight on the top can twist the rudder quite a bit when the stop at the bottom crashes. Many RV owners have experienced puncture damage in the skin from the inboard trailing edge of an elevator.

The .75" dimension is a conservative estimate in what clearance would be needed to prevent this (It has not been tested for a specific wind gust and it is not a guarantee).

A little bit less might be fine. Particularly if you are very careful about not ever letting your rudder be loose in the wind.:eek:
 
Rudder gap

I had almost your exact same results when I first hung my rudder. My feedback for Vans was that I would have rather made the rudder stop slightly on the larger side and been able to file it down to the acceptable limits vs have to make an addition offset piece and rivet it on. I was told the same information about the wind gusts and decided to leave mine as is.
 
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