| 摘要 |
A rotor-lift aircraft 100 has at least two rotors 106 mounted on spaced parallel axes. The propellers rotate in parallel planes in which the blade envelope subscribed by the rotor blade tips overlaps with the blade envelope subscribed by the rotor blade tips of another rotor without intermeshing of the blades. Preferably the rotors are shrouded or ducted 110, have the same radius and the bearing of one rotor is supported by the ducting structure of another rotor for compact arrangement. The rotor duct may comprise a through opening in a vehicle body, such as a hover bike for a pilot to sit on astride with a pair of rotors arranged in front and another pair of rotors arrangement behind the pilots seat. The vehicle may be a helicopter, an unmanned air vehicle (UAV), a toy helicopter, quad-copter, multi-copter, drone air craft, etc. |
