Forecasting both time varying MTBF of fighter aircraft module and expected demand of minor parts

A fundamental aspect of inventory management of fighter aircraft is to forecast the demand of minor parts installed in the main module. Most of the existing inventory models do not take into account the time-varying characteristics of modules composed of minor parts even though the demand rate of minor parts is sensitive to the conditions of module. In this paper, we propose random-effects regression models to forecast the mean time between failure (MTBF) of modules and the expected demand for the minor parts in the module based on time-varying characteristics of modules. Subsequently, we show how they can be applied to find necessary seasonal demand of minor parts. Our study is expected to contribute to ROKAF (Republic of Korea Air Force) in terms of providing base information for inventory policy for minor parts.