Which of the following best describes the risk associated with a spinning propeller?

• A. The loads are extremely high.
• B. It is lightweight and unhazardous.
• C. It runs quietly with low stress.
• D. It requires little maintenance.

Answer: (B)

Spinning propellers embody a lot of energy that translates into very high loads on the blades, hub, and mounting when they accelerate, decelerate, or encounter gusts. Those extreme dynamic and centrifugal loads create real risk of structural failure, blade separation, or a hazardous strike if someone is nearby or if debris is thrown. That combination—high energy and high loads during operation—is what drives the primary danger.

The other statements don’t fit the risk profile. A propeller is not inherently lightweight and unhazardous, and it does not run quietly with low stress, nor does it require little maintenance in a way that would negate the hazards of a spinning blade.