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RV-7, Elevator alignment bust with HS replacement

B

BruceW

Well Known Member
Will try to keep this short as possible.

Replaced the HS due to SB-00036 crack. (I had a spare HS from insurance from a bullet hole. Another story) Installed the SB-00036 kit onto the new HS just because. Rigged the new HS to fuse, installed right elevator as is. Elevator horn hole lined up well with the HS center hinge bearing. Left elevator was off a little, say 1/16+/-"). Solved by turning the two elevator rod-end bearing out one full turn. (Cant explain why the new misalignment)
Finished connecting things up, including the elevator horns to the pushrod using existing holes.

NUTS! Now elevator trailing edges dont match. left elevator is about 3/16" down from right side. Not surprised since lengthening the left rod-end bearings.

What to do ???
Options . . .
- Drill new hole on elevator horns for pushrod bolt rearward with needed edge distance. (this would require lengthening pushrods via multiple rod-end bearings)
- Weld doubler onto left elevator horn and redrill; either at center hinge bearing or pushrod connect.
- Find a way to turn the elevator rod-end bearings back to original.
- Replace left elevator horn and redrill both the HS center hinge bearing and pushrod.

Not liking ANY of the options since replacing the HS has been a royal pain already. Thoughts appreciated. Will also be asking Vans.
And no, I will not "just fly it and find out how it trims" cuz I know a 3/16" elevator trailing edge distance will cause a roll that should not be 'trimmed out".
Thanks.
 
Turn the other (right?) rod ends out one turn as well?

Otherwise I'd be thinking about welding up the pushrod hole in the horn, and redrilling it. I suspect support will say replace parts, but let us know the advice!
 
Vans replied with pics and text to remind me of the drilling techniques.
Not sure they understood this was a new/old install.
For error drills, Vans recommended TIG welding to fill the holes and redrill.
Will pursue that.


Now, the rest of the story . . . . (many years ago)
Walked into the hanger and notices light in the metal roof thru a small hole.
Dont remember seeing that before. Later, I noticed a narrow 1" long dent with crack on the top right HS skin. About 1" back from the leading edge. Searching the floor I found a 7.62 bullet on the floor. It came thru the roof, hit the leading edge with enough force to crease/crack the skin but not penetrate.
Argh, if bullet had hit a little forward, would have missed the HS.

Insurance paid for parts to a new HS assembly. But I was heading to Osh so I dressed the crack and smoothed out the skin then prosealed a larger patch on the skin. Lasted 8 10 years and 500 hours with no problems.
 
IMHO, you could have used poetic license and made up a more exciting story than that! :p:p
 
Alignment subtlety

Is the one elevator up as observed at the outboard counterweight areas? Could it be that the HS has a little twist?

Also, be sure that the bolts can all slide freely whether the elevators are at full up, full down or in the middle (the bolts which pass through the rod ends). This subtlety is often missed. Some incorrectly assume proper alignment has been achieved as long as the bolts can be slid in easily when the elevator is at neutral. The goal is all five holes being in a straight line.
 
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