To maintain rotor balance when blending, which action is sometimes required?

• A. Making an identical blend on the blade 180 degrees opposite to maintain rotor balance
• B. Removing two opposite blades
• C. Balancing only the non-bladed portions
• D. No balancing action is necessary

Answer: (A)

Blending changes the weight of a blade, and that weight change shifts the rotor’s mass distribution. To keep the rotor balanced through each revolution, you mirror the blend on the blade that is opposite it by 180 degrees. This symmetrical removal preserves even centrifugal forces around the hub, maintaining balance.

Other options don’t achieve that symmetry: removing two opposite blades isn’t the standard method for correcting a single-blade weight change and could introduce new balance issues; balancing only non-bladed portions ignores the weight change on the blended blade itself; and no balancing action is needed is incorrect because material removal alters balance.