摘要 |
<p>A rotor assembly (5) for a rotorcraft, such as a helicopter, includes rotors (7) rotatable about a hub (17). The assembly (5) is operable to vary the angular speed of the rotors (7) about the hub (17), relative to one another. The assembly (5) may include a drive operable to drive each of the rotors (7) at a different radial distance from the hub.</p> |