现代大型客机的刚体运动模态频率和弹性模态频率之间的差距越来越小，其在机动过程中的刚弹耦合问题也愈发明显。传统的六自由度飞行动力学仿真无法模拟这种刚弹耦合过程，这无论是对于控制律的优化，或者是飞行训练模拟器的研制都是不利的。通过分析大型客机的基本运动特征，选用平均轴系法对传统六自由度飞行动力学方程进行了扩展，搭建了大型客机的刚弹耦合飞行动力学仿真模型，既继承了原有的仿真体系，又大大简化了分析过程。同时，利用该刚弹耦合仿真模型分析了大型客机典型的俯仰机动和滚转机动下的刚弹耦合问题，与试飞结果进行了对比，验证了刚弹耦合仿真模型的准确性，并利用该模型研究了大型客机的典型俯仰及滚转机动条件下的刚弹耦合特征以及刚弹耦合对动稳定性及弹性模态的影响特性。

The difference in the frequency of rigid-body mode and the elastic mode of modern large passenger aircraft is becoming smaller， and the problem of rigid-elastic coupling during maneuvering is becoming increasingly apparent. Traditional flight dynamics simulation with six degrees of freedom cannot simulate this rigid-elastic coupling process， which is unfavorable for the optimization of control laws or the development of flight training simulators. By analyzing the basic motion characteristics of large passenger aircraft， we use the mean axis system method to extend the traditional flight dynamics equation， and construct a rigid-elastic coupling flight dynamics simulation model for large passenger aircraft， significantly simplifying the analysis process while inheriting the original simulation system. Meanwhile， the rigid-elastic coupling simulation model is used to analyze the typical rigid-elastic coupling problem of large passenger aircraft under pitch and roll maneuvers， with comparison with flight test results to verify the accuracy of the model. The model is then adopted to study the rigid-elastic coupling characteristics of large passenger aircraft under typical pitch and roll maneuvers， as well as the impact characteristics of rigid-elastic coupling on dynamic stability and elastic modes.