Rail Transit Shared Use andControl Systems Study

Since the 1990s, there has been growing interest in shared use of general railway system railroad rights-of-way and tracks by transit vehicles (such as light rail vehicles) that do not fully comply with Federal Railroad Administration (FRA) regulations that govern the existing freight and commuter rail services on the system. This has prompted several research efforts and initiatives by transit operators. Since the Rail Safety Improvement Act of 2008 requires the implementation of Positive Train Control (PTC) on a significant portion of the general railway system to improve the safety of railroad operations, this research was undertaken with the goal of evaluating the potential to use PTC to facilitate the sharing of railroad rights-of-way and tracks that are under FRA oversight. The research reviewed currently-active transit services that have obtained temporal separation waivers from FRA; analyzed the functionality of existing PTC systems and identified the lessons learned in the development of these PTC systems; evaluated the feasibility, risk, and reliability of current PTC technologies for shared use operations; and identified the changes needed to PTC systems and underlying signal systems they enforce to enable shared use operations. In addition, the research prepared the outline for a scope of work for a potential demonstration project that would use Signal and PTC technologies to facilitate shared-use operations under a waiver from FRA.