The Volpe Center has been conducting research into rail equipment crashworthiness in support of the Federal Railroad Administration's (FRA) Office of Research and Development. As part of this research, full-scale crash tests of passenger cars have been performed. Subsequent detailed post-test examinations develop an improved understanding of the collapse mechanisms of the dominant structural elements as well as overall dynamic crash behavior. This knowledge can be used for interpreting test data, estimating energy dissipation during the test, developing detailed finite element models, and designing safer passenger cars.