An aircraft had an empty weight of 2886 lbs with a moment of 101673 in-lb before alterations. After removing two pax seats at +71, installing a cabinet (97 lb) at +71, installing a seat and safety belt (20 lb) at +94, and installing radio equipment (30 lb) at +94, the new empty weight CG moved 1.62 inches aft of the original. If the original empty weight CG was +35.21 inches, what is the new CG?

An aircraft had an empty weight of 2886 lbs with a moment of 101673 in-lb before alterations. After removing two pax seats at +71, installing a cabinet (97 lb) at +71, installing a seat and safety belt (20 lb) at +94, and installing radio equipment (30 lb) at +94, the new empty weight CG moved 1.62 inches aft of the original. If the original empty weight CG was +35.21 inches, what is the new CG?

• A. +36.83 inches
• B. +36.00 inches
• C. +37.50 inches
• D. +35.21 inches

Answer: (A)

The concept being tested is how the center of gravity shifts when weight is added or removed at different locations. The CG is the balance point of the airplane, found by dividing the total moment by the total weight. Here, the original empty weight CG is +35.21 inches. The problem states that after the alterations, the new empty weight CG moved 1.62 inches aft. Moving aft means the CG increases in value, so you simply add the shift to the original CG: 35.21 + 1.62 = 36.83 inches. Therefore, the new CG is +36.83 inches. This reflects that the net effect of the changes places more weight toward the aft, despite some forward removals and near-term aft placements of the added items.

The concept being tested is how the center of gravity shifts when weight is added or removed at different locations. The CG is the balance point of the airplane, found by dividing the total moment by the total weight. Here, the original empty weight CG is +35.21 inches. The problem states that after the alterations, the new empty weight CG moved 1.62 inches aft. Moving aft means the CG increases in value, so you simply add the shift to the original CG: 35.21 + 1.62 = 36.83 inches. Therefore, the new CG is +36.83 inches. This reflects that the net effect of the changes places more weight toward the aft, despite some forward removals and near-term aft placements of the added items.