Positive train control in North America

Railroads are safe, and this safety is due to the traffic control and communication technologies that were introduced in the first half of the 20th century. Modern versions of these traditional technologies continue to provide safe and sound train movement by ensuring the integrity of the generation and delivery of the authorities provided to train crews to advance down the track. With that stated, however, accidents do occur in that very few of these technologies protect against actions of the last remaining major source of operational errors made by the train crews themselves. The technologies that have been available for such protection have been either too expensive or not available for other than selective mixed freight/passenger corridors, e.g., the Northeast Corridor. However, based on advanced positioning and communication technologies, a new surge in both traffic management approaches for productivity purposes as well as train control for safety purposes, referred to as positive train control (PTC), have been underway for two decades in anticipation of the implementation across freight operations. The material presented henceforth provides a basic understanding of rail operations followed by a discussion on the workings and considerations of deploying PTC, as evidenced by the development of CSX's PTC effort referred to as communication-based train management (CBTM). Railroadese used in this article is shown in italics.