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 fiber-optic 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 restricts speed limits and serves as a failsafe system. If the engineer doesn’t respond, the PTC system takes over to prevent a train from running a red signal light or entering a stretch of track at an unsafe speed.

The Authority will implement next-generation technology, Automatic Train Control (ATC), of which PTC is a subset. ATC is service-proven technology used on rail in Europe and Asia that ties in additional safety measures, such as intrusion detection and earthquake detection. 

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

  • Metrolink, Southern California’s 512-mile regional passenger rail network received $81.5 million through the California High-Speed Rail Program, helping it become the first railroad in the nation to have its entire system in service with positive train control technology.
  • Caltrain, Northern California’s main passenger rail service along the Bay Area peninsula, received $105.4 million through the California High-Speed Rail Program to install positive train control technology along the operations corridor.
  • North County Transit District in San Diego County received $41.8 million through the California High-Speed Rail Program to install positive train control technology along major operational corridors.
  • Caltrans received $2.9 million through the California High-Speed Rail Program to install positive train control technology along the BNSF rail corridor between Los Angeles and Fullerton which currently serves Metrolink, Amtrak, and BNSF rail services.

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