In CG calculations, what quantities are used to determine the center of gravity?

• A. Only total weight
• B. Total moments and total weight
• C. Only payload weight
• D. Temperature and pressure

Answer: (B)

CG calculations hinge on how heavy the airplane is and where that weight sits relative to a reference point. To find the center of gravity, you compute the total moments (the sum of each load’s weight multiplied by its distance from the datum) and the total weight (the sum of all loads). The center of gravity is then the total moment divided by the total weight. This shows why you need both quantities: total weight alone doesn’t tell you where the weight is concentrated, and total moments alone don’t tell you how heavy the aircraft is overall.

Temperature and pressure don’t enter the basic CG location calculation, even though they can affect density and performance. They aren’t used to determine where the CG lies.

So the quantities used are total moments and total weight.