| 摘要 |
<p>A VTOL aircraft (10) (or other vehicle such as a sea vehicle) includes a pair of elongated ducts on opposite sides of the vehicle body, and a plurality of powered propellers (or other propulsion units such as jet engines) mounted within and enclosed by each of the elongated ducts (134a, 13b), such as to produce an upward lift force to the vehicle. Each of the elongated ducts has a short transverse dimension slightly larger than the diameter of the blades of each propeller (14, 15) enclosed thereby, and a large transverse dimension slightly larger than the sum of the diameters of the blades of all the propellers enclosed thereby.</p> |
