Micrometeorid/debris protection of the COLUMBUS pressurized module

The ESA laboratory module Columbus, part of the NASA space station Freedom, has to be protected against micrometeoroid and space debris impact. For this purpose, an experimental simulation study is presently carried out at the light gas gun acceleration facilities of the Ernst-Mach-Institut. Various types of bumper shield arrangements, i.e. mainly dual and triple Al-plate systems of different plate thicknesses, but also systems of other materials, including laminate hybrid systems, are being tested with respect to their terminal ballistic effectiveness. Al- and Ti-spheres within a realistic mass and velocity range, representing essentially space debris, are used as hypervelocity projectiles. Fundamental impact damage phenomena are investigated and used for optimization procedures. Application of so-called "multi-shock concepts", i.e. multi-plate bumper systems, yielded most favourable results concerning areal material densities and respective protection effectiveness. Preliminary tests with FRP-plates (fiber reinforced plastics) and laminate bumpers resulted also in very promising protection characteristics.