如何精确解算高空飞行器被动段运行轨迹是航天测控领域研究热点与难点问题。在分析空间飞行器受力状况基础上，建立了严密飞行器运动状态方程，采用层次聚类分析方法构建了落点数据质量控制方案。通过仿真试验研究了空气阻力、地球引力和积分迭代步长等要素对飞行器运行轨迹影响，检验了落点预报质量控制方案可行性和有效性。结论表明：提出的数学模型能够高精度地解算出飞行器被动段运行轨迹，实现了落点位置自动化预报处理。

How to accurately track the flight trajectory of altitude vehicle at unpowered phase is the hot and tough problem in the field of space measurement and control. Based on the analysis of forces acting on the flight vehicle, its rigid movement state equation has been established, and the quality control scheme has also been put forward adopting hierarchical clustering technique to figure out the precise position of impact point. The feasibility and effectiveness of the suggested quality control scheme has been illustrated by simulated example, in which the influence caused by air drag, gravity and iterative step has been researched. The conclusion shows that the flight trajectory of altitude vehicle at unpowered phase could be accurately calculated with offered mathematics model, and the impact point could be automatically estimated.