飞机的坠撞性能是其结构安全性设计和评价的关注焦点，而机身框段与全机结构坠撞响应的关系是一直未厘清的问题之一。首先以典型民机全机和含舱门机身框段为对象，开展垂直坠撞实验研究，对实验结果进行对比分析。然后建立典型民机全机坠撞动力学模型，基于全机坠撞实验数据对模型进行验证。进一步通过模型剪裁方法获得含舱门机身框段、前机身等直段以及后机身等直段坠撞动力学模型，开展实验工况下的仿真分析，并基于仿真计算结果探讨不同机身框段坠撞响应与全机坠撞响应之间的差异性。结果表明：建立的全机坠撞动力学模型具有较高的预测精度，机体动响应和损伤预测结果与实验结果一致性较好，机身框段模型的剪裁方法准确；含舱门机身框段和后机身等直段的地板下部结构变形、地板加速度均小于全机结构，加速度峰值最大偏差达13.6%，破坏模式也相差较大。而前机身等直段的地板下部结构变形大于全机结构，但地板加速度仍小于全机结构，加速度峰值最大偏差达17.2%，揭示了全机与机身框段实验件的边界条件和能量输入差异是造成坠撞响应存在较大区别的本质原因；在飞机适坠性验证和评估中，针对不同的验证目标要采用不同的验证方法和对象，采用全机结构进行适坠性验证最为真实，采用框段结构可对坠撞仿真模型进行验证，可以支撑基于仿真分析的飞机适坠性评估；此外，含舱门机身段和后机身等直段在坠撞过程中受飞机机头和尾部收缩段的影响较大，不宜作为飞机适坠性的验证对象。采用前机身等直段作为飞机适坠性验证对象时，需要对实验件的端框进行加强，尽可能模拟实际的边界刚度条件。

The crashworthiness of an aircraft is the focus of its structural safety design and evaluation， and the relationship between the fuselage frame segment and the full-aircraft structure in terms of crash response has been one of the unresolved issues. In this paper， a vertical drop test with a fuselage frame segment with cabin door and a typical full-scale civil aircraft were conducted， and the results were compared. Then， a dynamic model of the full-aircraft crash was established and validated based on the experimental data from the full-aircraft crash. Furthermore， the model trimming method was used to obtain the crash dynamics models of the fuselage frame segment with a cabin door， the forward fuselage， and aft fuselage， and simulations were conducted under the experimental conditions. Based on the simulation results， differences between the crash responses of different fuselage frame segments and the full-aircraft structure were explored. The results show that the established full-aircraft crash dynamics model has high predictive accuracy， the predicted dynamic response of the structure is consistent with the experimental， and the deformation and movement process of the structure are consistent the experimental results， proving the accuracy of the model trimming method. The deformation of the floor structure and the floor acceleration of the fuselage frame segment with a cabin and the aft fuselage are less than those of the full-aircraft structure， the maximum deviation of the acceleration peak is 13.6%， and the damage modes are significantly different. For forward fuselage， the deformation is greater than that of the full-aircraft structure， but the floor acceleration is still less than that of the full-aircraft structure， with a maximum deviation of the acceleration peak reaching 17.2%. This reveals that the boundary conditions and energy input of the full-aircraft and the fuselage frame segment experiment pieces are fundamentally different， leading to significant differences in crash response. the verification and evaluation of aircraft crashworthiness， different verification methods and objects should be used for different verification targets. Using the full-aircraft structure for crashworthiness verification provides the most realistic results， while using the fuselage frame segment can verify the crash simulation model to support the simulation-based aircraft crashworthiness assessment. Additionally， fuselage segment with a cabin door and the aft fuselage are greatly affected by the contraction of the aircraft’s nose and tail during a crash， and thus are not suitable as verification objects for aircraft crashworthiness. When using the forward fuselage as the verification object for aircraft crashworthiness， the end frame of the experiment needs to be strengthened to simulate actual boundary stiffness conditions as closely as possible.