提高高旁通飞机引擎的方法之一就是把风扇变成开放式旋翼，有点回归于螺旋桨的味道，但要使用两圈粗短的反旋桨叶。

One way to increase the efficiency of a high-bypass jet engine is to turn the fan into an open rotor, a bit like returning to propellers, but using two rings of stubby counter-rotating blades.

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21世纪初，另一种新型飞机是仿转式旋翼飞机，它能够垂直起落和水平飞行。

At the beginning of 21 centuries, another kind of new-style plane is copy turns type autogiro, it can perpendicular rise and fall and level fly.

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