Vulnerability of Space Station Freedom Modules: A Study of the Effects of Module Perforation on Crew and Equipment

Orbital debris penetration of manned spacecraft is accompanied by a number of atmospheric effects that can pose a serious hazard to spacecraft and crew survival. These atmospheric effects can include overpressure, light flash, and temperature rise as hot particles formed during the penetration process impinge into the atmosphere of a manned spacecraft. This report presents the results of a combined experimental/analytical study sponsored by the NASA/Marshall Space Flight Center and performed by the University of Alabama in Huntsville (UAH). The experimental effort consisted of a series of light gas gun tests in which orbital debris particle simulants were fired through space station module wall mock-ups into a large test chamber simulating the interior cabin of a spacecraft at 1 atm. The test chamber was instrumented with pressure transducers, light sensors, and temperature gauges to measure the level of blast hazard associated with differing target and impact conditions. The analytical effort consisted of the development of an analytical model for the various internal effects that accompany the perforation of a habitable module by an orbital debris particle. The model characterizes the phenomena comprising the impact event, including the initial impact the creation and motion of a debris cloud within the module wall, the impact of the debris cloud on the inner wall, the creation and motion of the debris cloud that enters the module interior, and the effects of the debris cloud within the module on module pressure and temperature levels.