What is the CG range used in many weight and balance problems, expressed in inches?

• A. 40-60 inches
• B. About 60 inches to 78 inches.
• C. 70-90 inches
• D. 80-100 inches

Answer: (B)

The distance from the datum to the center of gravity is expressed in inches because the datum is a fixed reference point along the fuselage, and the CG must stay within a defined window to ensure safe handling. In many weight-and-balance problems, the allowed range is about 60 inches forward to 78 inches aft from the datum. This window reflects the balance between having enough stability (not too far forward) and keeping enough elevator authority and controllability (not too far aft) for typical operations.

So the standard CG range used in these problems is roughly 60 to 78 inches. Ranges that are much shorter or much longer than this—such as 40–60 or 70–90 or 80–100 inches—either push the CG too forward or too aft for the typical aircraft configurations these problems base on, and thus aren’t representative of the common problem setup.