Predicting the perforation response of honeycomb sandwich panels using ballistic limit equations

Man-made debris from previous spacecraft missions poses a serious threat to spacecraft that are launched to operate in Earth orbit because it can strike such spacecraft at extremely high velocities and consequently damage mission-critical systems. Most satellites are constructed with honeycomb sandwich panels as their primary structural elements. To be able to perform a risk analysis, it is important to know, in the event of such a meteoroid or orbital debris particle impact, whether or not the impacting particle or parts thereof will exit the rear of the sandwich panel. A recently developed set of ballistic limit equations for two different types of honeycomb sandwich panels are studied to determine how well they perform when they are applied to systems that are outside of the database that was used to develop them. It was found that these ballistic limit equations are fairly conservative; they successfully predicted sandwich panel perforation in nearly all of the tests that resulted in perforation, while allowing approximately half of the nonperforating tests to be incorrectly labeled as tests with a perforation. This indicates the likelihood that use of these equations in design applications could result in overly robust shielding hardware.