Sparing Criteria. Clear Management Approach

Reference is made in this paper to the possibility of defining logistic system parameters, allowing the Logistics Sensitive Operational Availability (LSOA) usage. To this end, a parameter of Back Order Probability (BOP) was introduced, allowing calculation of the Average Wait Time per Order (TWAIT), which, together with the Weighted Demand Rate (WDR) expresses the Mean Logistic Down Time (MLDT). The mechanism of the effect of spares quantities on the Availability was analyzed, taking into account different Indenture Levels (IL) and different Levels Of Repair (LOR) in a multi-echelon case. Algorithms for calculation of BOP, TWAIT, LSOA and Operational Readiness (OR) were developed with consid eration of the Poisson Distribution of demands. In addition, a proper technique for total cost constraints calculation, adequate for sparing application, was established.