03/11/2023 - Elevator trim - 2h

Another attempt at tweaking and tuning the elevator trim tab in order to reach it's target values of max 25degrees up and 35 degrees down.
One of the issues I noticed is that the lower edge of the tab is interfering with the rear of the elevator on order to move further down.

I bent the bottom skin of the tab slightly to allow it to get more room.

 Back to adjusting the pushrod length and giving it another try.

Down movement is now going down to 28.7 degrees which is already a lot better than where we came from. Down trim pulls the elevator up which results in a nose up or climb movement

Back to the level reference point

The trim up value is now +15.8 degrees. I have read that the down deflection is important to be more significant than the up deflection. Up trim pulls or adjusts for the force neede to push the elevator down. Elevator down move the nose down for descent.

I'm more please with these number but will try to do some research what other builders values look like when I get closer to flight testing. I'm gonna leave this as is right now.

 

 

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