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Old 8th December 2006 | 20:37
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Mad (Flt) Scientist
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Joined: Sep 2002
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From: La Belle Province
if x is the reference point for the "leading edge" of the mac and "mac" is the length of the mac, then:

c=(a-x)/mac
d=b/mac

(which will give you cg as a fraction of mac; if you want it as a %age, then multiply then both by 100, i.e
c=100*(a-x)/mac
d=100*b/mac)

To prove this, consider that you already know:

h=a-(RA*b)/W

and if you know x and mac, then:

cg=(h-x)/mac

therefore

cg=( [a-(RA*b)/W] - x)/mac

= (a-x)/mac - [ (RA * b)/(W * mac) ]

= (a-x)/mac - [ (RA/W) * (b/mac) ]

so if cg = c - d RA/W, then c and d can be simply seen from the equation

Last edited by Mad (Flt) Scientist; 8th December 2006 at 20:38. Reason: added example for *100
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