Shielding electronics behind composite structures

The increasing use of composite structures and composite electronics boxes in space can result in a several-fold increase in electronics radiation total dose, as compared to using aluminum structures and aluminum electronics boxes. There are also desires to use multi-function structures (MFS), where electronics are integral with composite structures (no electronics boxes). MFS approaches can result in an order of magnitude increase in radiation dose to electronics over conventional aluminum structures and boxes. The designer must either use rad-hard parts which are becoming more difficult to obtain since the end of the Cold War, increase spot shielding, use RADPAK/sup TM/ solutions, or add shielding to composite boxes and structures. With the increasing use of low hardness commercial parts to reduce costs, a brute force solution of adding shielding to composite boxes is frequently the lowest cost solution. Analyses, test data, and a flight experiment are described to assess these shielding options.