放宽静稳定度飞机时间延迟稳定边界

针对飞机初步设计阶段其放宽静稳定度（RSS）与电传飞控系统时间延迟边界之间的定量关系求解问题，以战斗机纵向短周期方程为基础，分析了飞控系统中的时间延迟因素，描述了放宽静稳定度与方程参数间的关系。并以等效输入延迟的形式构建了含飞控系统时间延迟的闭环系统特征方程，通过根轨迹趋势理论和数值计算方法确定了放宽静稳定度与飞控系统时间延迟边界的定量数值关系，同时探讨了舵效与动导的参数不确定性对所求时间延迟边界的影响。本文方法对飞机初步设计阶段飞控系统时间延迟指标和可放宽静稳定度边界的确定具有一定的工程实践意义。

Time delay stability boundary on relaxed static stability aircraft

The problem of quantitative determination between Relaxed Static Stability (RSS) and time delay boundary of the fly-by-wire control system during the preliminary design stage of aircraft is studied. Based on the longitudinal short-period equation of the combat aircraft, the time delay factor in the flight control system and the relationship between parameters in short period equation and RSS is analyzed. A characteristic equation of closed-loop system with time delay of flight control system is constructed in the form of equivalent input delay. The quantitative numerical relationship between the RSS and the time delay boundary of the flight control system is determined by the root tendency theory and the numerical calculation method. Moreover, the influence of the parameter uncertainty of control surface efficiency and dynamic derivative on the time delay boundary is also discussed. The method of this paper has certain engineering practical significance for determining the time delay boundary of the flight control system and the RSS of the aircraft in the preliminary stage of aircraft design.