Which claim about blade construction is correct?

• A. Shanks are partially hollow for weight reduction
• B. The blade is solid steel
• C. The blade is made of pure titanium
• D. The blade has no weight reduction features

Answer: (A)

Weight reduction through hollowing at the root area is a common design strategy for blades. The shank, which connects to the hub, carries high loads and experiences significant centrifugal forces, so engineers often make it partially hollow to lower the blade’s mass and inertial effects without compromising strength where the load is applied. This balance—keeping enough material where it matters for stiffness and attachment, while removing material to save weight—lets the blade perform better in rotation and vibration.

Having a blade that is solid steel would add unnecessary weight and could limit performance and balance. A blade made of pure titanium is unlikely for a standard blade because pure titanium is expensive and its properties aren’t typically optimized for the whole blade geometry in general aviation blade designs. And saying there are no weight reduction features contradicts established practice of optimizing mass distribution to improve efficiency and handling.