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Acro-II Ailorn Horn question


Aug 9, 2009
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I think that I have this one figured out, but I like to find out when all of you guys know something that I am missing.

I have plans SN 1521 dated 3/93. On sheet 14, the plans for the aileron horn seems to have a misprint. The arm that connects with the control rod from the mid-span idler angles up to align with the idler and have to control rod both horizontal in the wing and above the drag/anti-drag wires. The plans are drawn with an apparent angle of 15 degrees up. However, the plans say 3 degrees.

Laying out the height of the idler bracket and the aileron control horn on the spar as per plans, an angle of 15 degrees for the arm aligns it perfectly (horizontally along the spar) with the mid-wing idler arm. so everything seems to fit and line up and miss the drag/anti-drag wires if the arm is angled up 15 degrees.

So is the 3 degree measure on the plans just a typo? or am I missing something that I should be considering?

Just figured I'd ask before wasting all that welding rod...


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