The X2 uses a pusher propeller mounted at the rear and has a pair of contra-rotating main rotors, one positioned above the other.

它使用一个安装在后面的推进式螺旋桨并有一对一上一下反向旋转的主旋翼。

youdao

So, how studies can accurately prediction to the contra-rotating propeller hydrodynamic performance is more important.

所以，研究如何更能准确地预报对转螺旋桨水动力性能更为重要。

youdao

The thrust and the torque of the contra-rotating propeller has been calculated by this method, and its result is satisfying on the comparison and the analysis with the actual value.

通过该方法计算了对转螺旋桨的推力和转矩，并与实验值进行了比较和分析，其结果令人满意。

youdao

The X2 uses a pusher propeller mounted at the rear and has a pair of contra-rotating main rotors, one positioned above the other.

ECONOMIST: Chop, chop