I'm no engineer, but just a pilot trying to estimate the drag of my small two-place airplane from the relevant formulae.(adsbygoogle = window.adsbygoogle || []).push({});

My plane is quite draggy, and from comparison with other aircraft data, I have taken Cd,0 as 0.043. Apart from this, I calculate the induced drag at a given speed from the lift, equal to the weight in S&L flight, air density, wing area, aspect ratio and applicable Oswald number (I've taken 0.73). So far, so good, but I have doubts concerning the lift-dependent drag. In a solved problem in Anderson's Aircraft Performance and Design, the author estimates (for a Gulfstream) that lift-dependent drag as 1/3 of the induced drag.

Should I take that figure for my calculations? I don't feel sure, since 1/3 is a lot...

Thanks in advance...

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# Lift-dependent drag estimation

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