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Old 12-23-2009, 06:05 PM
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BMatthews
 
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Default RE: Airfoil for a MiG 15

You're quite right Himat (and a "chamber" is a room or large container. An airfoil has a "camber" line. Just trying to help out for next time.)

What is really needed is to look at airfoils where the Cl vs Cd has a lower drag bucket that crosses the Cl=0 axis of the graph. But choosing one that has too much of a shift to the positive side will generate more drag if loaded in the negative G direction. However if the emphasis will be on turns and positive G maneuvers there's some advantage in looking at a compromise section that still offers minimal drag at a CL=0 point while extending that minimal drag value up to a CL of perhaps .4 to .5.

Either way the camber would still be very low. Perhaps 1 to 1.5% at a maximum. From looking at a lot of lift vs drag graphs airfoils with even 1.5% camber often don't have a minimal drag bucket that extends to CL=0. And even at 1% for what it provides the builder would have to look at it and decide if the gains are worth the effort. The upper end shift of the minimum drag portion may only move up a little.