介绍一种发动机总冲精度预示的工程方法。利用编制的计算机软件，调整影响总冲精度的各参量公差范围，可控制固体火箭发动机的总冲相对偏差达到技术指标要求。通过几个实例，表明该方法有较好的实用性。同时还分析了控制发动机总冲偏差的有效措施，为设计者合理地制定发动机主要性能参数和结构尺寸的公差与技术条件提供了依据。 An engineering method for predicting the total accuracy of the engine is presented. Using the programmed computer software to adjust the tolerance range of the parameters that affect the total impulse accuracy, the total impulse deviation of the solid rocket motor can be controlled to meet the technical requirements. Several examples show that the method has good practicality. At the same time, it also analyzes the effective measures to control the total offset deviation of the engine and provides the basis for designers to reasonably set the tolerances and technical conditions of the main performance parameters and structural dimensions of the engine.