The Development of a Concurrent Spare-Parts Optimization Model for Weapon Systems in the South Korean Military Forces

The inventory level of concurrent spare parts (CSPs) has a significant effect on the availability of a weapon system. To improve the accuracy of CSP requirements, we developed a new version of a CSP optimization model that the South Korean military forces subsequently adopted. Our model has major improvements over its predecessor, including (1) combining failure rates from both user (i.e., the Korean military forces) field data and from predictions based on reliability handbooks; (2) modifying the shop-replaceable unit optimization logic; (3) adding an optimization process that uses genetic algorithms; (4) employing practical formulae to calculate operational availability; and (5) adding functions to increase the quality of the optimization results. Our simulation experiments identified that our model met the operational availability targets of the South Korean military forces and dramatically reduced the purchases costs of spare parts compared to the results generated by the previous version of the model.