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Old 11th October 2010 | 11:51
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PBL
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Joined: Sep 2000
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From: Bielefeld, Germany
I am having a little difficulty understanding what you are proposing. Here is why.

Originally Posted by HN39
c_L=1.3826*10^-4*W/(delta*M^2*S)
where W=weight (mass) in kg, delta=ratio of ambient to SLS pressure, M=Mach, S= (reference) wing area in m^2
Looking at the units, this is ((number) x Force) / (number x number x Area), i.e force per unit area. Let M be mass units, L be length units, T be time units. Force is then M x L / T^2; Area is L^2, so this comes down to M x L / T^2 x L^2, which is M / T^2 x L.

Whereas in the usual definition of c_L, which you quote as
Originally Posted by HN39
c_L ..... is commonly defined as LIFT/(q*S)
c_L has no units: (M x L / T^2) / ( (M / L^3) x (L/T)^2 x L^2 ) all cancels out.

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