Britain's beloved steam trains trial pioneering technology

"No steam locomotive in the world had ever been run with in-cab digital signalling – until now."

The word "digital" is doing a lot of work here: here in the US, the Pennsylvania Railroad had in-cab signaling back in the 20s. Here's an article about it [pdf] https://www.jonroma.net/media/signaling/railway-signaling/19...

With the recent mandate of Positive Train Control on all mainline trains in the US, some steam locomotives have been retrofitted with PTC, notably UP 4014 and CPKC 2816 (which seems to the be basically the US version of what the brits are doing here).

But regardless of pedantry, it's neat to see the reassurance that they'll be able to operate on modern mainlines safely.