The Consolidated Support Model (CSM) can be used to examine logistics support structures, including: (1) the current structure with its three levels of maintenance (depot, intermediate, and base) and a two-echelon (depot, base) supply system, and (2) variations on the current structure in which resupply decisions come from a central stockage point in a region, while repair is accomplished either at the central stockage decision point or at individual operating bases. CSM provides a more refined methodology than the model used in earlier MPIP studies for assessing the supply impact of the centralized intermediate logistics concept. CSM optimizes spares allocation in three-echelon supply systems and accounts for the hierarchical relationships that exist in many recoverable components of new weapon systems. Two other approaches for computing requirements are compared with the CSM using F-15 data pertaining to avionics items. Flying-related backorders are expected to be much greater when using either of these alternative models. 39 pp. Ref.