All other things being equal, if an item of useful load located aft of an aircraft's CG is removed, the aircraft's CG change will be....

• A. Forward in proportion to the weight of the item and its location in the aircraft.
• B. Backward in proportion to the weight of the item and its location in the aircraft.
• C. No change.
• D. Upward.

Answer: (A)

Center of gravity is the point where the aircraft’s weight is considered to act; it’s the weighted average of all weights and their distances from a reference datum. If you remove a piece of useful load that is behind the CG, you’re taking away weight that was contributing to a rearward moment. That reduction of aft moment shifts the balance toward the front, so the CG moves forward.

Think of the CG as a balance point: removing mass behind that balance point reduces the tipping force toward the rear, causing the balance point to move forward. This follows the basic idea that CG is the sum of weight times arm, divided by total weight. Removing aft weight reduces both the total weight and the rearward moment, with the net effect of shifting the CG forward.

This isn’t about vertical position, so “upward” isn’t applicable. And the change is not zero because removing weight changes both the total weight and the moments contributing to the CG.