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I am trying to measure elevator travel while the mixer rudder frame is locked in the neutral position. The stop on the mixer plate limits the elevator up and down travel.

The up travel is given in the plans as 11 deg. as measured from the top surface of the stabilizer to the top surface of the ruddervator. This measures exactly as shown on the plans.

For the down measurement, a digital protractor on the ruddervator cannot be used because the angle of the Vee tail confuses the protractor that wants either horizontal or vertical surface movement.

So I measured the distance the ruddervator tip moves when aligned at neutral with the fiberglass tip. The movement down is 2-1/8". With a 10" distance from the hinge to the tip, it is opposite/adjacent = tangent(angle). So in this case, the angle is 12 degrees. The plans call for 20 degrees.

To get the 20 deg., I need 3-5/8" of movement at the tip from neutral, not the 2-1/8" I have.

1. What is the elevator travel that others have measured? I'm guessing the Waiex would be the same as the Xenos.

2. How did you measure the travel? The factory told me to use a digital protractor. Mine doesn't work in 3D.

3. How was travel increased if you did not have enough initially?

Rick Caldwell
Xenos 0057

Hi Rick,

Louise rigged our controls a few months ago, and I know that she got full travel, but haven’t asked her how - I know it was close.

In terms of measuring, we made cardboard angel templates - one for up, one for down), and used those to check the angles. I learned that trick on the Subsonex - using a digital level is wonky, as you discovered.

Paul

Thanks for the reply, Paul.

I went after it with a different approach today and drew out the outline in the three positions. Measuring with a protractor on the posterboard, I see I actually have 16 deg up travel and 12 deg. down. I can move 5 deg. to the down side with pushrod adjustment. This will get me 11 up & 17 down which is close given my measurement error band is a couple degrees.



Rick Caldwell
Xenos 0057

Here's my mistake.

Do not measure the down travel from the fixed fiberglass tip to the ruddervator tip. The measurement is made with the ruddervator top skin coincident with the top skin of the stab which is the neutral position.

This is about 3-5/8" which the tan formula gives 20 deg.

Rick Caldwell
Xenos 0057