Comparison of Lot-Sizing Methods in Aircraft Repairable Component Inventory Systems

The performance of single-level lot-size methods in the inventory environment of aircraft maintenance is studied. Many airlines have considerable difficulty in realistically tying together repair costs and inventory savings. This is because heavy and line maintenance inventories are not easily predicted nor is the consumption of parts, with daily airline operational business characterized by high fixed cost components. Results are presented of a comparison of alternative methods for determining appropriate purchase quantities within material requirements planning systems. Actual historical demands from airline component overhaul workshops were used to determine how lotsizing methods respond to different combinations of operating parameters in aviation maintenance. A total of 17 lot-sizing methods have been considered. Visual examination of the results were the main focus of this analysis. Finally, a set of guidelines is included to enable airline inventory management practitioners to choose a lot-size method for particular operating parameters.