发动机工作的扰动是载机随机振动的重要来源之一。为探究载机随机振动对发射过程的影响，通过随机谐和函数法生成载机随机振动的位移激励；结合多体动力学理论和固定界面模态综合法，建立了后向弹射装置的刚柔耦合动力学模型，并在关键接触力处理中使用了分布节点等效集中力的简化方法。结合GF-d选点法与直接概率积分法（DPIM）求解了关键部件的响应概率密度函数及应力的统计特性，不同采样数的仿真统计特性对比误差小于1.25%，验证了结果的收敛性；多工况仿真关键部件的应力统计特性及可靠性评估表明，该弹射装置具有极高的可靠性。为具有随机激励的机载后向弹射系统的建模、响应的统计分析及系统可靠性评估提供了一种可信高效的解决途径。

The disturbance generated by engine operation is a primary source of random vibration in the carrier aircraft. To investigate the impact of carrier aircraft random vibration on the launch process, a displacement excitation model for this vibration is constructed based on the stochastic harmonic function method. Integrating multibody dynamics theory and the fixed-interface component mode synthesis method, a rigid-flexible coupled dynamic model of a rearward ejection device is established. A simplified approach, which treats distributed nodal forces as equivalent concentrated forces, is employed to handle key contact forces. The GF-d point selection method combined with the Direct Probability Integral Method (DPIM) is utilized to solve the probability density functions of the response and the statistical characteristics of stress for critical components. ?Comparisons of the simulated statistical characteristics with different sample sizes show an error of less than 1.25%, thereby verifying the convergence of the results. Furthermore, simulations under multiple working conditions, analyzing the stress statistics and reliability assessment of these critical components, demonstrate ultra-high reliability, with failure probabilities below 10 ppb of the ejection device. It provides a credible and efficient approach for the modeling, statistical analysis of responses, and system reliability assessment of airborne rocket rearward ejection systems subjected to stochastic excitations.