修理级别分析(LORA)是舰载机保障性分析的重要内容，对舰载机全系统、全寿命保障具有重要的意义。现有的LORA分析模型对装备使命任务、作战使用和保障体系考虑不够全面，不能全面确定舰载机维修级别决策，影响装备的作战使用与保障体系决策。基于此，提出基于备件期望短缺数(EBO)的LORA分析模型。首先，分析了舰载机的维修保障模式；其次，结合舰载机保障实际建立了EBO的多级保障模型；再次，给出了基于EBO的优化分析模型；最后，结合实例对基于EBO的LORA问题进行了应用分析。

Level of Repair Analysis (LORA) plays a significant role in Integrated Logistics Support Analysis of shipboard aircrafts,and is important for whole-system and whole-life management of the aircrafts.The current analysis model of LORA problem is insufficient for equipment mission and logistics support system.The analysis model is incomplete for LORA decision-making,and may affect the operational use and logistics support decision.To solve the problem,an analysis model of LORA is presented based on expected backorders (EBO) of spare parts.Firstly,the maintenance support mode of shipboard aircraft is analyzed.Then a multi-stage EBO model is established based on the actual situation of shipboard aircraft logistics support,and an optimization analysis model is presented based on EBO.Finally,analysis is made to the application of EBO based LORA according to an actual example.