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<b>Message ID:</b> 16043 <br/>
<b>Date:</b> Mon Mar 13 21:34:28 GMT 2000 <br/>
<b>Author:</b> kim@stormhaven.org <br/>
<b>Subject:</b> RE: [eqbards] The view from the sky (Plane of)... <br/>
<br/><br/>
<div id="ygrps-yiv-881605518">On Mon, 13 Mar 2000, Reeves, Patrick W wrote:<br/>
<blockquote><span title="ireply"> &gt; <br/>
&gt; But John, what is the air speed of an unlaiden swallow? lol :p<br/>
&gt; -------------------------------------------------<br/>
&gt; Rokenn Swiftsong - Karana server<br/>
<br/>
 </span></blockquote>Drag on a body in a fluid is:<br/>
<br/>
D = Cd*pi*r^2*rho*Vo^2<br/>
<br/>
Cd = coefficient of drag of the swallow<br/>
pi = 3.1415...<br/>
r = radius of bird cross-section (approximating as a circle)<br/>
rho = viscosity of air<br/>
Vo = velocity<br/>
<br/>
For steady state flight, D (drag) = T (thrust), so:<br/>
<br/>
Vo = sqrt(T/Cd*pi*r^2*rho)<br/>
<br/>
--<br/>
John H. Kim<br/>
<a rel="nofollow" target="_blank" href="mailto:kim@...">kim@...</a></div>