Crossrail has reached a “major milestone”, after successfully running multiple trains in close formation through the tunnels.

The achievement was marked in an announcement made by Crossrail chief executive Mark Wild.

It comes after Wild revealed that one of the main causes for the delay related to systems tests due to outstanding work, when he revealed his project post-mortem in January having been drafted in to the project shortly before the end of 2018.

“Dynamic testing didn’t work a year ago [because of] two simple reasons: the signalling integration hadn’t been completed, and you can’t test something which hasn’t been installed,” he said at the time.

A new programme of dynamic testing then re-started in January this year.

The new milestone in carrying out the first close headway testing with multiple trains in close formation was hailed as a “big step forward for our ambition to be into full trial running in the early part of 2020” by Wild.

“On Sunday 8th June we achieved a notable milestone for this remarkable project. The first close headway testing with multiple trains in close formation,” Wild said.

“Congratulations to my team, Siemens and Bombardier for this milestone. There is a long way to go but the testing was positive.”

He added: “A big step forward for our ambition to be into full Trial Running in the early part of 2020.”

A Crossrail spokesperson added: “Work at Crossrail stations continues as we complete the final fit-out and testing of key systems. During the weekend we commenced close-headway multi-train testing in the tunnels and is another important step forward in the dynamic testing phase.”

In April this year, a revised six-month window for opening was announced with the earliest date pinned as October 2020 and the latest being March 2021.

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