Abstract: In order to study the module partition of Line Replaceable Unit (LRU) in the process of military aircraft testability design, a module partition scheme of LRU for military aircraft is designed based on the principle of reducing the fault location time and fault isolation time in the maintenance and support stage of military aircraft. Firstly, a macro-level initial partition model based on Product Lifecycle Management database is constructed to realize the initial partitioning from the whole aircraft to the system and then to the subsystem or equipment. Then, a module partition clustering algorithm of LRU based on the key components of equipment is developed. In the algorithm, on the basis of obtaining the key components of the equipment by using Pareto principle, a comprehensive evaluation factor is constructed aiming at the cost and time during the military aircraft's whole life cycle of design and customization stage, maintenance and support stage, end-of-life stage. By the comprehensive evaluation factor, the optimal combination of non-key components and the interacted targets with them is realized, and finally a LRU partition scheme is formed. Taking the system layer design of a military aircraft as an example and the subsystem or equipment layer design process of the aircraft's environmental control system as an example, the preliminary division module of the macro-level is validated and the verification results are consistent. The LRU module of the evaporative cycle refrigeration device in the aircraft environmental control system is divided by using the LRU module partition clustering algorithm, and the partition results are compared with the actual LRU inventory of the device, comparisons show that the results are consistent with each other.

Key words: partition of line replaceable unit, key component, partition clustering algorithm, life cycle, comprehensive evaluation factor, evaporative cycle refrigeration device