Positive Train Control

Positive Train Control (PTC) is state-of-the art collision avoidance technology that allows trains, tracks and dispatch centers to actively communicate using a dedicated fiber-optic and radio network.

Through PTC, train engineers receive continuous information about speed restrictions, work zones and other safety impacts. For example, the PTC system would alert an engineer approaching a crossing where the crossing arms are malfunctioning. With PTC, a train's onboard computer displays safe-braking distance based on speed, train length, weight and track curvature. PTC also restricts speed limits and serves as a failsafe system. If the engineer doesn't respond, the PTC system takes over, thus preventing a train from running a stop command or entering a stretch of track at an unsafe speed.

Select numbers on the Illustration below to learn more about PTC

Illustration with a high-speed train crossing diagonally through the scene, a satellite, radar, and tower are communicating with the train; vehicles are parked at gates which are blocking the track as the train passes; an operator is monitoring conditions from computers.

PTC Quick Facts

How California High-Speed Rail is supporting PTC statewide

Photo of construction team wearing safety equipment and working on concrete structure.

Resources

Contact

Safety
(916) 324-1541
info@hsr.ca.gov