Brightline West and California High-Speed Rail: What Signalling Systems Will They Use?

The deployment of modern signalling and train-control systems is a critical enabler for the next generation of high-speed rail in North America.

Two of the most significant projects on this frontier are Brightline West and California High‑Speed Rail (CHSR). Last week, the Wayside Digitalisation Forum (WDF) conference in Vienna shed some light on the signalling plans for these networks, with a keynote speech by Jonathan Hu and Richard Plokhaar, Senior Technical Directors at WSP.

Hu and Plokhaar provided an overview of the signalling landscape in North America, but stressed that current technologies, specifically Positive Train Control (PTC), is only certified for speeds of up to 80 mph. Brightline West and California High-Speed Rail are therefore anticipated to adopt the European Train Control System (ETCS), with permission from the government to go beyond Buy America regulations.

Brightline West

Brightline West is a planned 218-mile, fully electric high-speed rail line between Las Vegas and Southern California (Rancho Cucamonga), running primarily in the median of Interstate 15. Trains are expected to run at speeds of up to 200 mph.

Siemens Mobility has been selected as the preferred bidder to supply the American Pioneer 220 trainsets, built for US standards and with “future interoperability with California High‑Speed Rail” in the procurement criteria. This interoperability will include shared technical standards and a shared signalling system, such as ETCS.

California High-Speed Rail

The California High-Speed Rail Authority (CHSRA) is developing a statewide high-speed rail system – electrified, steel-wheel-on-steel-rail, capable of up to 220 mph.

In the official planning documents, the signalling and train-control architecture is described as a “state-of-the-art safety and signalling system.”

The primary system is designated as an Automatic Train Control (ATC) system, which subsumes several layers: Automatic Train Protection (ATP), Automatic Train Operation (ATO) and Automatic Train Supervision (ATS).

For communications, California High-Speed Rail planning documents specify a fibre-optic backbone with radio towers spaced approximately every 1.5-3 miles (2–3 km) depending on terrain. This will support wireless data for train-control, signalling and communications.

On the signalling technology options, the documentation considers European standards such as European Train Control System (ETCS) Level 2 with GSM-R as an “attractive, compliant and low-risk” path for implementing the ATC and radio network.

This approach aims to adopt a high-standard globally-proven signalling/ATC architecture rather than retrofitting conventional US signalling.

The exact signalling supplier(s) for either project have not yet been selected, and a timeline is not yet known.

Both Brightline West and California High-Speed Rail will embrace signalling systems that go well beyond legacy US freight/regional railroad practices. For CHSR, the specification clearly calls for a full ATC architecture, wireless communications, and alignment with global high-speed standards (e.g., ETCS). For Brightline West, while public details are less complete, procurement signals strongly indicate a future‐proof system that aims to be interoperable with CHSR and capable of high speeds and modern train control.

Notably, the challenges remain substantial: cost per mile, procurement risk, system integration, communication backbone reliability, regulatory alignment and interoperability across vendor platforms. For the North American high-speed rail scene, the choices made by these two projects may well set the benchmark for subsequent corridors.