Requirements analysis for a multi-spacecraft flight system

The StarLight mission, scheduled to be launched in June 2006, will demonstrate the separated spacecraft technologies of formation flying, precision formation estimation, and long baseline stellar interferometry. The StarLight flight system consists of two spacecraft that will launch as a stacked cluster, separate from each other after a short post-launch checkout, and then operate for at least six months in an Earth-trailing heliocentric orbit. A variety of demonstrations will be performed at inter-spacecraft separations of 30 m to 1000 m. In order to fully describe the StarLight flight system requirements, we have had to introduce several new dimensions into the typical requirements analysis process. This paper will describe the flight system requirements analysis approach, and will also show how we have organized a preliminary set of these requirements within our project requirements database. We believe our approach can be extended to flight systems with larger collections of cooperating spacecraft.