先进战斗机纵向飞行特性与放宽静稳定度研究

放宽静稳定度在先进战斗机设计领域已获得广泛应用，与其相关的主动控制技术仍有进一步研究的价值，需要对放宽静稳定度对飞机纵向飞行性能的影响进行更全面的分析。以重心后移作为放宽静稳定度的方式，分析放宽静稳定度与某型战斗机俯仰力矩系数的关系，构建战斗机非线性模型并进行开环特性分析，在此基础上，分析放宽静稳定度对飞机运行平衡点的影响机理，对战斗机非线性模型进行线性化，并分析放宽静稳定度对飞机纵向线性模型阶跃响应特性和长短周期模态特性的影响。结果表明：放宽静稳定度可增大战斗机的俯仰力矩系数，提高飞机性能，但可能会使飞机本体模态特性变差，需要在设计控制率时予以考虑。

Study on Longitudinal Flight Characteristics and Relaxed Static Stability of Advanced Fighter Aircraft

Due to relaxed static stability are widely used in the field of advanced fighter aircraft design, in this paper, based on the related data of a certain type of advanced fighter aircraft, The influence of relaxation of static stability on the total pitching moment coefficient of this type of fighter is analyzed. A aircraft six degrees of freedom nonlinear mathematical model is constructed , whose open-loop characteristics which is effected by the relaxing static stability is analyzed .Secondly, the influence of the relaxed static stability on the aircraft motion equilibrium point is analyzed, and the nonlinear mathematical model of the aircraft is linearized based on the small disturbance theory. On this basis, the influence of the relaxed static stability on the step response characteristics and the long and short periodic mode characteristics of the longitudinal linear model of the aircraft is also analyzed .The influence of relaxed static stability on the longitudinal flight performance of aircraft is analyzed from the above multi-mode and multi-angle.