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Sure LOOKS like an Aileron Spar...


Premium Member
Aug 18, 2006
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Sleuthing hat donned...I have these long pieces of spruce carefully beveled...Because they are all the same length (56") I assumed they were prepared for building ailerons. The general shapes match the shapes of the aileron spars (a trapezoid). However, the dimensions are significantly off from what is in my plans.

The plans call for spars with the widest part (the base of the trapezoid) ~2-9/32" (I am going from memory) for the lower ailerons, and something very similar for the uppers. The largest trapezoidal cross section piece I have is under 2 inches on the base...and I have another set of pieces that are smaller still.

When I slide the routed aileron ribs onto these spars, they are obviously too small to work.

The other "clue" is that the aileron spars should be 54" plus change, so the pieces of wood I have are too long - if this were the only problem I'd be willing to accept that the previous builder left them long intending to trim them down when he fit them to the aileron well in the wing. That is the guidance Mac provided in the Builder's Guide, at least.

So far every part I've inherited from the previous builder has been precisely made, so I assume these pieces of wood (there are on the order of 10 separate pieces with different cross sections, all 56 inches long) belong somewhere...

Any ideas off the top of your heads?


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