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Old November 4th 06, 02:19 AM posted to rec.aviation.piloting
Larry Dighera
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Posts: 3,953
Default How to tell my instructor to increase glidespeed with headwind?

On 3 Nov 2006 10:45:01 -0600, T o d d P a t t i s t
wrote in
:


You only fly at min sink for better distance when the
tailwind is infinite. At any slower tailwind speed, you fly
somewhat faster than min sink, but not as fast as best
glide.


http://www.glidingmagazine.com/CommD...d=178&RootId=0
McCready theory usually uses the formula

Sink rate = a x V^2 - b x V + c

where a, b and c are the parameters to fit. This formula has the
advantage that it makes the math much nicer, but the disadvantage that
it is just plain wrong, in the sense that it says that sink rate
increases like V^2 at high speeds, which it doesn't - it increases
like V^3, which is much faster!