First test train to use a new signalling system on the Northern City Line

The testing of the new digital signalling on the Northern City Line has commenced with the running of the first Great Northern train between Finsbury Park and Moorgate under the new system.

The testing is carried out with a Great Northern Class 717 train and marks an important milestone in a project that will ultimately see traditional signals removed from the tracks along this route. Digital signalling intends to reduce delays and hence offer a more reliable service.

The first test train ran in the early hours on Sunday 29 May.

Test train in the Moorgate tunnel (c) Network Rail

An ongoing period of testing will ensure that the train fleet, already fitted with the necessary technology, works well with the new digital signalling infrastructure that will communicate directly with the train’s cab.

Testing is taking place overnight and at weekends and will carry on throughout 2022 to ensure complete assurance of its safety and reliability, with driver training and migration to digital signalling operations due to commence in early 2023.

The Northern City Line is expected to switch over to solely using digital signalling in 2024.

This milestone follows on from a test carried out with a Class 717 in the Thameslink ‘core’ between St Pancras and Blackfriars using digital signalling in ETCS (European Train Control System) Level 2 in September last year. A Class 717 unit ran using the Thameslink ETCS system (3.4.0 onboard over 2.3.0d trackside). The testing now being undertaken on the Northern City Line involves similar equipment.

Once the Northern City line has been fully upgraded, the lessons from that project will feed into the larger project to upgrade the entire East Coast Mainline railway.