I have been stuck working on the elevator trim tab.  I needed to fabricate the horn and install it in order to adjust the servo push rod and ran into a problem with the drawing of the horn.  It does not fit the clevis of the RCS-7 Clevis kit supplied with the CH601 kit.  I worked to modify the horn to fit the clevis, positioned it and drilled ready for rivets and found that I had placed the rivet hole to close to the fold  and I am unable to place a rivet correctly.  Ordered a new part, and received a totally different part.  It is a better part, lighter, four rivets instead of two and it wraps around the trim tab skin.  So, now I am left with two A5 rivet holes which I have decided to fill in with rivets and move on.  

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Comment by Bradford Drown on September 1, 2019 at 7:44pm
I am concerned that maybe I should fabricate a new horn that is thicker like my original and the one called for in the plans. Still will need to see the 650 plan to utilize or add a relief notch to this part.
Comment by Glenn Davis on August 31, 2019 at 4:44am


The picture with my post is from the plans.

Here is the link to the forum post on this issue.



Comment by Bradford Drown on August 30, 2019 at 7:23pm
Hi Glenn,
Do you have a photo of the failed part? Or a picture of that fabrication in the plans? Sounds like a safety issue I should look at. Thanks.
Comment by Glenn Davis on August 30, 2019 at 5:42am

Hi Bradford,

The plans for the 650 show a relief notch on the radius for the trim tab horn angle. The factory part does not have this notch. I suffered a failure of this part at that radius in flight which was not an experience I would recommend.

I don't know if the notch would have helped in my situation but it's on the plan for a reason.



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