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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舞台可正反旋转，由红外遥控控制！

Stage can reverse rotation, by an infrared remote control!

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可以手动设置转速、扭力、扭力保护、急停、正反旋转、程序锁定，密码设置与输入。

Can manually set the speed, torque, torque protection, emergency stop, positive and negative rotation, program locking, password Settings and input.

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