Low Mass Components for Mars Ascent Propulsion

The Jet Propulsion Laboratory is planning a sample return mission for early in the next century. To accomplish this, the Mars ascent stage must be landed on the Martian surface and then, after actuation, ascend to Mars orbit. Given this mission profile it is necessary to develop propulsion components of substantially lower mass than were previously available for spacecraft applications. Low mass is especially critical to the Mars ascent stage because mass reduction of this stage affords the greatest leverage for the reduction of the total mission system mass at Earth liftoff. In addition to very low mass, these components must be rugged, reliable, and compatible with fuel, oxidizer, pressurant gas, and environmental extremes. Three separate components were developed for a liquid bipropellant baseline stage propulsion system: A high-flow etched-disk filter with a mass under 90 g, an all-metal miniature fill and drain/vent valve with a mass under 9 g, and a miniature high-flow check valve with a mass under 20 g. The design and development of these components as well as test data are summarized. (Author)