What do expandable bolts on the main rotor assembly facilitate?

• A. Improved aerodynamic efficiency
• B. Easy folding of the blades
• C. Reduction of vibration during flight
• D. Enhanced structural rigidity

Answer: (B)

The correct answer highlights that expandable bolts on the main rotor assembly allow for the easy folding of the blades. These bolts are designed to create a secure connection while also enabling the rotor blades to pivot or fold when necessary, for example, during storage or transport of helicopters. This design feature is crucial for aircraft that require a smaller footprint when not in operation, therefore enhancing the versatility and functionality of the rotor assembly.

Understanding how these bolts work gives insight into their importance in rotorcraft design. They not only contribute to the operational capabilities of the helicopter but also ensure that the blades can be managed in a way that doesn't compromise their structural integrity. By facilitating the folding mechanism, expandable bolts ultimately improve maintenance and transport processes, which are essential in aviation operations.