Tourists riding San Francisco’s famous cable cars in the 1990’s were probably unaware that they were part of one of the most challenging urban rail networks in the United States.
The cable cars’ cousins, the tramways, used on longer routes, had reached capacity – not for lack of cars or space, but because of an antiquated control system. Five lines converged on one central tunnel every trip, and the regulation to find their slots was done manually by the conductors themselves. This bottleneck allowed only 23 trains per hour to pass; not enough for the growing number of users.
One option was to build another tunnel, but with huge costs and traffic disruptions. Instead, the city opted for Thales’s new signalling technology: Communications-Based Train Control (CBTC). This could increase capacity at much less cost and, since it worked with both old and new trains, with minimal service disruption. It was successful – the CBTC system cut down the timing (headway) between trains in the tunnel substantially, increasing their number to a sustained 48 per hour, more than doubling capacity, and up to 60 per hour during delay recovery.
By using digitalisation and mobile communication, CBTC does not need conventional trackside equipment; it relies instead on active and central control of trains, with enforced stops and precise spacing depending on traffic flow. This greatly improves safety, reliability, capacity and flexibility, while saving on operational and maintenance costs. It can also enhance passenger information systems, data collection and security. And of course it is cybersecured by design.
Moreover, CBTC systems can be easily upgraded, using Thales’s expertise in connectivity, big data, and cybersecurity, leveraging the Group’s experience in the defence, security, and avionics sectors. Operators can manage network growth, extensions and fleet expansions without any unplanned disruptions.
No wonder Thales’s most recent generation of CBTC systems, SelTrac™ G7, has become the world-leading automated train control solution. Used by dozens of cities to transport more than three billion passengers a year, it also paves the way for autonomous train operations.
“SelTrac™ G7 maximises passenger throughput, accurately controlling the position of each train. It increases revenue by moving more people more quickly and is easy to expand and adapt, lowering life-cycle costs. Most importantly, SelTrac™ passengers will enjoy a safer, faster and more predictable commute,” says Duncan Lewis, Transport & Security General Manager at Thales.