Looking at DWG #17 of the EROS plans (wing spar construction) I notice the upper struct attachment reinforcement is RS9 but the lower reinforcement is RS8 for both front and rear spars. I assume this is a design decision based on loads (Gs?, landing?) limitations/expectations. (e.g. 1100 plans have only upper reinforcements on rear spar) One ramification of this is that the RS9 diagonals require notching at the end for gussets to fit appropriately. My question is, hypothetically, other than very small weight difference and need to shorten verticals in that section, as well as make the RS23 filler in rear 1 1/8 width instead of 1 1/4), what would be ramification of just using RS9 for both upper and lower reinforcements? Gussets would lay flat without notching. Am I missing something else that would be impacted?
I realize notching the diagonals is not really a big deal. Just curious if there are other reasons beside my assumptions about loads on upper vs lower attachment points that design decision was to use different stock for upper vs. lower reinforcements.
Again, not a biggie. Just trying to learn more. Thanks!
Tony
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