Trades and problems in the definition of the Columbus operation concept

This paper describes rationale, criteria and resulting concepts and problematics related to Columbus/Space Station operations.Its content, whilst acknowledging basic operational principles developed by NASA, is based on ESA and European National studies and its conclusions illustrate a consistent and coherent European approach.Starting with the European experience in unmanned and manned operations, the essential new features of the operation of the foreseen manned orbital infrastructure are briefly described. The main aspects governing the approach to future space operations design and implementation are highlighted and criteria for assessing this implementation are discussed.This is followed by illustrative discussion of how specific operational functions can be implemented.Problems and unresolved issues are also identified. rf;)