Army helicopters hovered overhead.

军直升机在空中。

What the team discovered is that the key to the hoverfly’s successful hovering is the flexibility of its wings.

这个小组所发现的是，食蚜虻在空间成功的关键是牠的翼的柔韧性。

A theory of aeroelastic stability of hingeless rotor blade in hover by using the Galerkin weighted residual finite element method is developed in this paper.

辽金加权余数有元素法发展了一状态下无铰旋翼桨叶气弹稳定性的分析方法。