That is partly because of increasing vibration, but mainly because the spinning rotor blades provide both lift and propulsion.

直升机旋翼既要提供升力又要提供向前的推力是造成这一情况的主要原因，同时旋翼产生的震动也是一个让直升机飞不能高速飞行的部分原因。

youdao

Due to its two interacting 242 R2R lift motors, the carer can both lift and position the patient while in the sling during the transfer.

由于它的两个相互作用的242 R2R电梯电机，照顾者既可以解除病人和位置而在吊在转移。

youdao

Both lift line model and generalized wake model are founded in this paper. A method is given for calculating induced velocities by a wake vortex line which results in a rapid convergence.

建立了旋翼升力线模型和广义尾迹模型，在计算角迹涡线诱导速度时，采用了快速收效方法。

youdao

That is partly because of increasing vibration, but mainly because the spinning rotor blades provide both lift and propulsion.

ECONOMIST: Chop, chop

But such a monetary boost would push down the yen, and so both lift exports and push prices up.

ECONOMIST: The new danger

This growth should be enough to both lift considerably more homeowners out of negative equity in 2013 and persuade more potential sellers to list their homes and help ease supply constraints in some areas.

FORBES: Mortgage Settlements Not Likely To Move Housing Market