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Elevator trim range of motion

Hey folks, decided to power up the RV-10 trim servo and noticed that, at full deflection, the bellcrank goes below the bracket (see https://youtu.be/V504XJwrg64) , which seems like it would be an issue. Is this expected? Perhaps you'd never trim the aircraft this way in practice but wondering if there's a way to adjust the travel to avoid this.
 
Trim

If you fabricated it per the plans, it will work fine. I don’t think I would start modifying the elevator trim...
 
Once it’s all together, you’ll see that one tab (I think it’s right) actually runs slightly backwards at full trim tab up.
 
Once it’s all together, you’ll see that one tab (I think it’s right) actually runs slightly backwards at full trim tab up.

Indeed! I finally got everything hooked up last weekend (only to take it apart again) and it acted exactly as you say. Also observed that when right tab is full up, left is slightly down. You can see this in a video I shot. Based on other reports of this I adjusted to correct this. Video of trim test is here.
 
Built as per the plans you can get this asymmetric tab issue.

You do not want this defect. Fixed as you have is a good thing.
 
This ‘defect’ is at full nose down trim, which virtually never is needed. What you really want is to have both tabs the same at typical cruise/loading.
 
This ‘defect’ is at full nose down trim, which virtually never is needed. What you really want is to have both tabs the same at typical cruise/loading.

+1

Tim Olson has a good write up on this. If you follow the plans for adjusting the trim cables, you will likely have asymmetrical tabs at neutral (I did), putting a constant twisting force on your elevators. Wise to read this article, as it provides a good plan for modifying the setup approach to avoid this.

Larry
 
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