Low-Cost and Low-Risk Thermal Changes to Cool Landsat-7 Solar Array Drive Slip Rings

National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) requires the maximum analytical temperature limit for solar array drive (SAD) slip rings to be 50°C based on previous flight programs. With the baseline thermal control, the Landsat-7 peak slip ring temperature prediction significantly exceeded the requirement. The initial options of changing the slip ring assembly shaft material from titanium to aluminum or filling the hollow center of the titanium shaft with copper could reduce the slip ring temperature significantly. However, they have high technical risks and significant impacts on the program cost and schedule. This paper presents low-risk and low-cost thermal changes to reduce the peak slip ring temperature prediction to below 50°C.