共轴式直升机悬停纵向稳定性和操纵性分析

基于准静态假设，研究了共轴式直升机悬停纵向稳定和操纵性，给出了稳定性条件和动稳定性与静稳定性的关系及改善稳定性的方法；最后给出了气动导数和悬停高度对稳定性和操纵性的影响。研究表明：共轴式直升机悬停纵向振动运动主要表现为不稳定的周期性运动，而静稳定性和静操纵特性是成正比的。研究结果对进一步研究共轴式直升机的纵缶操纵稳性能具有一定的参考价值。

Longitudinal stability and control of a coaxial type helicopter in hovering

Based on pseudo static assumption, the study of longitudinal stability and control in hovering for a coaxial type helicopter is presented, we also give the condition of stability and educe the relations between static stability and dynamic stability through it. Final, the influence of hovering height and aerodynamic derivatives on stability and control is proposed. The results of research indicate that the coaxial helicopter will represent its longitudinal motion as the non stationary periodicity when hovering, and static control is relevant to static stability. Above all results are of significance in order to study stability and control on coaxial helicopter in future.