In this study, a Secondary Impact Protection System (SIPS) consisting of an airbag and a deformable knee bolster for use on a modern freight locomotive was developed and tested. During rail vehicle collisions, a modern locomotive designed to current crashworthiness requirements should provide sufficient survival space to the engineer in cab. However, without additional protection against secondary impacts, a locomotive engineer could be subjected to head, neck, and femur injuries that exceed the limits specified in the Federal Motor Vehicle Safety Standards (FMVSS 208). The SIPS study aimed to design a system that would control these injuries within the limiting criteria.
Simulation results for the design concept showed that it would meet the FMVSS 208 criteria for the head, neck, chest, and femur, injuries and continuing to meet all existing functional requirements of the locomotive cab.
A sled testing of the prototype showed that to optimize the SIPS, further airbag design modifications, characterization and testing are required.