Analysis of the Impact of Variation in Mean Time Between Demand on Air Force Fleet Level Aircraft Parts Inventories

摘要

This thesis researched the accuracy of demand forecasting and impact of demand variation on requirements definition for Air Force aircraft secondary items. Specifically, this thesis sought to answer three questions: How does the Air Force calculate item requirements, How accurate is the current system at predicting future item requirements, and How do variations in predicted demand change item requirements. The literature review described the Air Force supply system for aircraft secondary items. Analysis into current demand forecast accuracy found that the level of error between actual and predicted historic demand was as high as 92% for the items studied. Furthermore, this analysis identified a flaw in the calculation used by supply specialists to measure demand forecast accuracy. Research found that demand rates are the most influential factor in computing item requirements. A 50% change in TOIMDR resulted in a Total Gross Requirement change of 33%. A 25% increase or decrease in TOIMDR created a 16% respective change in Total Gross Requirement. This thesis concluded by providing recommendations for effective accuracy measures and future research topics to improve item requirement forecasting.