| 摘要 |
A rotor assembly is disclosed herein. The rotor assembly includes a hub disposed for rotation about an axis of rotation. The rotor assembly also includes at least one blade fixed with the hub for concurrent rotation with the hub. The at least one blade extends along a height axis radially outward from the hub with a root portion proximate to the hub at a first end of the height axis and an airfoil portion extending radially inward from a second end of the height axis opposite the first end. The rotor assembly also includes a sheath extending at least partially around the root portion. The sheath is pivotally engaged with the at least one blade to pivot about the height axis and allowed to weathervane to reduce noise. |
