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Posted by 6Killer | Mar 25, 2011 @ 06:51 AM | 2,819 Views
Center of Gravity

Having returned to the hobby of RC flying after many years I have forgotten much. The term Center of Gravity has been confusing to me. I decided to research the term a bit and here are a few of the things I found.

From here:
http://www.wikihow.com/Calculate-Center-of-Gravity
I found this:
The center of gravity (CG) is the center of an object's weight distribution, where the force of gravity can be considered to act. It is the point in any object about which it is in perfect balance no matter how it is turned or rotated around that point. For a finite set of point masses, CG may be defined as the average of positions weighted by mass. That is, the (Sum of mass*position)/(Sum of mass)

I offer my thoughts on the subject as one who is still learning. So if I miss anything important or say something off target, please add your concept.

I am finding that there are several centers. There is a geometric center. see:
http://www.grc.nasa.gov/WWW/K-12/airplane/cg.html

A geometric center in the above assumes a uniform distribution of mass, but does not address aerodynamics.

There is a center of mass as described here:
http://en.wikipedia.org/wiki/Center_of_mass

Center of mass simply put, for me, it is where a thing balances, but says nothing about aerodynamics or where the plane flies well.

And there are CG calculators like this one:
http://fwcg.3dzone.dk/

When you look at what a CG calculator does it is really only a geometric center calculator because it...Continue Reading
Posted by 6Killer | Nov 25, 2010 @ 02:00 PM | 3,134 Views