OK, I sat CAA(NZ) exam for Rotorcraft today, 94% (yay!), but one question bothers me. Lateral Centre of Gravity calculation had me guessing.
So, arms left of centreline are negative, arms right are positive. I have loads and arms for left and right fwd scales, rear scale is on the centreline.
The way I figure, lateral CoG arm is
left weight x left arm(-)=left moment
right weight x right arm(+)=right moment
LW+RW=WT, LM+RM+MT, CoG(lat)=WT/MT.
But it isn't. For some reason I need to use the aft scale reading aswell,even though that lies on the centreline (ie; 0 arm=0 moment),to give a total weight, and divide that by the total L/R moment to get the lateral CoG position. Why?
