Research shows that, it is suitable for rotor dynamics, dynamic analysis of helicopter rotor blades fuselage systems and piping systems contained flow fluid.

研究表明，本方法适用于转子动力学，直升机旋翼-机身耦合系统以及具有流体流动的管道系统的动力分析。

youdao

Then there's increasing the number of rotor blades. This helps because each additional blade carries less of the weight of the helicopter, and thus produces less noise.

增加旋翼桨叶数量也是一种方法，这使得每片桨叶负载的直升机重量降低了，因此产生的噪音更小。

youdao

But unlike an aircraft, when a helicopter is flying forwards the air passing over its rotor blades does so at different speeds.

但是与飞机不同的地方在于，当直升机向前飞行时，空气是以不同的速度流过旋转的叶片的。

youdao

When the helicopter began getting away from the pilot, he pulled back on the cyclic, which controls the pitch of the rotor blades, only to find the aircraft unresponsive.

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