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Ribs drawing

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Jun 30, 2014
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Hi all,

I have some problems to print the ribs on scale. U.S. A3 is not exactly the same as the French A3
I will draw the airfoil from coordinates, directly on the board, but before I need some clarification.
- Airfoil used is really a NACA 23015 ?
- What is the exact length of the CL of the rib. I have 58-1/4" but I'm not sure
- what is the exact measurement between the red arrows on the drawing below.



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