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Permalink Reply by Dr. Edward M. Moody II on September 5, 2010 at 3:21pm

Hi Edward,

In reality, you don't need any aileron counterweights for safety; the flutter incidents and suspicions that have been reported are almost certainly not harmonic flutter. You will be installing these weights to please the FAA, the NTSB, and the "perfect world" crowd. They may also bring good luck, however sinking a canoe, particularly a large canoe, is thought to bring bad luck in the culture of South Pacific Islanders, so don't do that with the excess weights unless you simply don't care about the superstitions of large smiling brown people.

Seriously, hang the aileron back on the wing with clecos once the counterweight arm is permanently installed and the hole is cut in the rear spar for the arm to move inside the wing. Use lots of clecos so that the flex hinge aluminum or the piano hinge flange is snug to the rear spar (the rear top skin would be elsewhere at this point). Don't do this while there are clecos on the aileron... their weight makes a difference. Just add weights using the TLAR method (That Looks About Right). Cut the last added weight if that achieves a better balance. Remember to use all of the hardware that will be in the final assembly (same bolt, washers, nut etc.) As George W. would have said, "It isn't rocket surgery".

Primer and paint aren't likely to make much difference after the assembly so don't sweat that; it's small stuff and eventually you may need to blame the crash on something, right? Have fun and remember to take pictures and document everything for the certification process. No help available for the prop; I run The Power From Down Under (Jabiru 3300A Hyd.)

Ed Moody II

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Permalink Reply by David Gallagher on September 5, 2010 at 5:00pm

Edward,

It seems that Zenith supplied enough weights to cover any builder situation and then added some for good measure. I too had several extra's. In fact, for me, the supplied bolts were too long so I must not have added enough weight, right? Well actually, no, but I have polished skins so mine weight the least of all. They had to pick a bolt length that they hoped would work for 'most' builders. Instead of adding a canoe load of washers, I bought some shorter bolts. Who knows, you may end up doing that also, so don't sweat it. If anybody has a canoe that needs some extra balance weights and 4 really long AN quality bolts, call me.

Dave

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