The formula is the sum of all moments both positive and negative divided
by the total weight regardless of what reference point is chosen.

Usually a reference point is chosen at the tip of the tractor spinner so

all the

moments are of the same sign. The CG position is then the distance aft from
the tip of the spinner. As I recall this is the way it is taught in PP

ground school.

Paul Lamar

George Lendich wrote:

Paul,
Right on the nose- if there is some confusion perhaps the book available
from Spruce Etc "Aircraft Weight and Balace" by Joe Schafer 1979, will
fill in any gaps.

George (down under)

 
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