The above unit makes the rotor head movable in one direction.

上述单位，使转子头动产在一个方向。

youdao

Helicopters require a tail rotor to counteract the rotor torque; this and the articulated head complicate flying, construction and maintenance enormously.

需要直升机尾桨抵消转子力矩；这和阐述头复杂飞行，建造和维修极大。

youdao

In a helicopter the articulated head and tail rotor gearbox are required to be a very high specification design using the best materials and requiring frequent and costly maintenance.

在直升机的阐述头和尾桨变速箱都必须是一个非常高规格的设计使用最好的材料和需要频繁和昂贵的维修。

youdao

It included the black box flight recorder, the fuselage with the engines and rotor gearbox attached, the separated rotor head with the main rotor blades still attached, and the separated tail.

BBC: Crash report urges safety checks

They placed explosives near the avionics system, the communications gear, the engine, and the rotor head.

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