Under these conditions, flapping, birdlike flight might well have some benefits over propeller-driven or helicopter flight.

在这种情况下，拍击，像鸟儿一样飞可能比螺旋桨推进飞行要好些。

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The propeller can't work well.

螺旋桨工作不稳定。

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It sets forth the computing method of rotor moment of inertia of the propeller and engine as well as the computing method of additional moment or angular velocity produced by precession.

阐述了螺旋桨和发动机转子转动惯量的计算方法，由进动产生的附加力矩或角速度的计算方法。

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