That modern armed helicopter flies at super low space makes radar system useless, so it is important to identify and locate a helicopter through its flying noise.

现代武装直升机的超低空飞行，使得雷达系统已经无能为力，因此通过直升机的飞行噪声对其进行识别和定位具有重要意义。

The flying control laws are implemented, thus realizing the helicopter autonomous flying under hover and low speed conditions.

最后，设计了飞行控制律，实现了在悬停和低速下的全自主飞行。

The mini electric helicopter is cut out for the beginner for its crash-proof, low cost of flying and easy for handling.

小电直拥有抗摔性能好、飞行成本低、飞行压力小等优势，非常适合电直入门者使用。