What is the main purpose of positive train control (PTC)?

The main purpose of positive train control (PTC) is to automatically stop or slow a train to prevent accidents. PTC systems are designed as a safety mechanism to reduce the risk of human error by taking control of train operations when necessary. They can intervene in situations where a train is approaching a stop signal, exceeding speed limits, or encountering obstacles on the tracks. By implementing these automatic controls, PTC significantly enhances the safety of train operations, ensuring that accidents caused by human oversights are minimized.

In relation to the other options, while they touch on aspects of train operation and safety, they do not encapsulate the primary function of PTC. Regulating train speeds based on weather or communicating with other operators are important aspects of rail operations but are not the central focus of what PTC is designed to accomplish. Similarly, tracking train locations in real-time is a component of train monitoring systems but serves a different purpose than the main safety objectives of PTC.