The Advantages and Disadvantages of Seeking Commonality in Military Equipment

Increasingly, the Army and the Department of Defense DoD are developing families of systems built around common, base platforms so that variants share many key components. For instance, the Army has procured Stryker armored combat vehicles, which is a family of vehicles sharing a common base platform and thus most key components. Commonality can increase operational flexibility and reduce procurement, logistical, and training costs and burdens. However, commonality can also decrease design freedom and occasionally negatively affect operational capability by forcing design compromises to accomplish multiple missions, none ideally. And commonality can actually increase costs if it overly increases design complexity or if some variants end up with excessive functionality. These factors suggest that the pursuit of commonality should be informed by careful analyses. To help the Army determine how to more effectively incorporate the full range of commonality considerations in weapon system development and acquisition, RAND Arroyo Center assessed the advantages and disadvantages of commonality and developed a decision aid to help Army policymakers manage these tradeoffs. The study drew upon historical and literature analyses as well as case studies of commercial and military efforts to exploit commonality.