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Ailern Plywood Q

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Premium Member
Aug 18, 2006
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I'm still playing the sleuth trying to figure out what I inherited from the previous builder of my Firebolt.

I'm looking at the lower (symmetrical) ailerons. I'm looking specifically at sheet 11 of my Firebolt plans (I believe the sheets are numbered the same between the Skybolt and the Firebolt).

On this diagram, there are two versions of triangular pieces of plywood 2" x 0.5" x 0.5" used in the trailing edge of the aileron as rib tip reinforcements. They are parts #15 (outer edges, 2 req'd per aileron) and #16 (8 req'd per aileron, for the inner ribs). The outer ones are supposed be be fabricated from 5-ply 1/4" birch, and the inner ones are made from 3-ply 1/8" birch.

My previous builder cut these, but he used 5-ply mahogany (1/4") for the 8 inner ribs reinforcements and 5-ply 1/4" birch for the outer ones.

Why did he do this?

On this sheet, the plan-view dimensions of part number 16 are not shown, just the thickness/ply...however, I was able to figure out what they should be by looking at Sheet 9 for the upper ailerons: Parts 95 and 96 are the identical parts here, and there is a detail view showing their dimensions.

I'm still getting the hang of looking at my blueprints...

I have more questions, but we'll start with this one.


Edited by: CKeller

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