Abstract Aircraft Maintenance Repair and Overhaul (MRO) is essential to ensure aviation safety and air transport operations. An aircraft has to temporally suspend its service and receive extensive maintenance in the hangar upon reaching the prescribed flying hours and take-off/landing times. Traditionally, each airline company undertakes hangar maintenance for its own fleet, however the nature of MRO operations has changed with the rapid development of air transport demand. Outsourcing hangar maintenance to maintenance service companies has been increasing among airlines, enabling airlines to reduce the cost of MRO while meeting the aircraft’s safety requirements. After receiving the maintenance order with specifications, the maintenance service company needs to determine the maintenance schedules, parking stand allocation, aircraft movement path and staff assignment in the integrated planning problem. To integrate the abovementioned factors, a Mixed-Integer Linear Programming (MILP) model is developed. In the MILP model, geometric factors are considered, which are integrated with the multi-skill manpower assignment afterwards. Consideration of staff with multiple types of maintenance skills, aligning with the practice of sophisticated hangar maintenance, is incorporated in the model. Secondly, given the complexity of the integrated problem, a two-stage optimization approach is developed by decomposing the original model, which is coordinated by the linkage constraints between the geometric and numeric decision-making scattering in the decomposed subproblems. The results and analysis of numerical experimentation are reported, which shows: (i) the adaptability and efficiency of the two-stage optimization approach and (ii) the tractability of the two-stage optimization approach, which manage to produce good quality solutions in solving medium- to large- size instances. The impacts of maintenance demand intensity and manpower supply variation are also analysed to provide managerial insights.

中文翻译：

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MRO外包下飞机机库维修规划及人员分配问题的两阶段优化方法

摘要 飞机维护修理和大修 (MRO) 对于确保航空安全和航空运输运营至关重要。飞机在达到规定的飞行时间和起飞/着陆时间后，必须暂时停止服务并在机库中接受大量维护。传统上，每个航空公司都会为自己的机队进行机库维护，但随着航空运输需求的快速发展，MRO 运营的性质发生了变化。航空公司将机库维修外包给维修服务公司的情况越来越多，使航空公司能够在满足飞机安全要求的同时降低 MRO 成本。维修服务公司收到有规范的维修订单后，需要确定维修时间表、车位分配、综合规划问题中的飞机运动路径和人员分配。为了整合上述因素，开发了混合整数线性规划 (MILP) 模型。在MILP模型中，考虑了几何因素，然后将其与多技能人力分配相结合。该模型考虑了具有多种维护技能的员工，并与复杂的机库维护实践保持一致。其次，考虑到集成问题的复杂性，通过分解原始模型，通过分解子问题中几何和数字决策散射之间的联系约束来协调两阶段优化方法。报告了数值实验的结果和分析，结果表明：(i) 两阶段优化方法的适应性和效率，以及 (ii) 两阶段优化方法的易处理性，在解决大中型实例时设法产生高质量的解决方案。还分析了维护需求强度和人力供应变化的影响，以提供管理见解。