A variation of the Centaur launch vehicle will be used as a high-performance upper stage to launch spacecraft from the Space Shuttle cargo bay into geosynchronous orbit. As an element of the Shuttle payload, Centaur must be designed to avoid contaminating sensitive spacecraft surfaces. Nonmetallic materials used in structural and electronic applications can exhibit high rates of outgassing in a space vacuum and contaminate critical spacecraft surfaces of varying temperatures as condensation occurs. Judicious material selection, per NASA specifications, is used to control instances of such contamination. Vacuum baking is permitted by NASA Specification SP-R-0022 to "bake out" potential sources of organic contamination. Most Shuttle/Centaur missions are planned for spacecraft having surfaces of various temperatures in locations that are susceptible to condensation of organic outgassing products. To determine the extent of potential contamination, General Dynamics has initiated a test program with the White Sands Test Facility that is designed to measure outgassing and condensation rates of nonmetallic components in their use configuration. This paper reviews the tests, equipment requirements, sensor instrumentation, and some of the results to date.

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