Successful testing at speed has been completed of upgraded digital software on a Thameslink Class 700 unit, preparing the largest passenger fleet on the East Coast Main Line (ECML) for the introduction of in-cab digital signalling.
The 115-strong Thameslink fleet is the largest passenger fleet in the Government funded £1.4 billion East Coast Digital Programme (ECDP). ECDP will transform the way rail services are provided by replacing traditional, lineside signals with continuous information displayed inside drivers’ cabs, delivering a more reliable, greener and even safer railway.
Over two separate Sunday evenings in April and May, a GTR Class 700 Thameslink train was tested in the Central London ‘core’ section of Thameslink (the section between London Bridge and St Pancras International), using European Train Control System (ETCS) version 3.6.0, an upgrade of the digital signalling software. The testing work was carefully planned to ensure no disruption to the start of Monday morning passenger services at 4:30am.

GTR is currently the only operator in the UK using ETCS 3.6.0 in passenger service, on its Class 717 fleet and this builds on the experience gained using digital signalling on the Northern City Line. The testing, done in collaboration between GTR, Network Rail, and Siemens Mobility, was carried out to ensure the train’s existing functions continue to operate normally alongside the benefits of the upgraded software.
The upgraded software allows more flexibility for services to operate in a high traffic area like the ECML by connecting the train to the trackside via GPRS, using ‘packet switching’.
The first passenger services to use ETCS on the ECML (between Welwyn Garden City and Hitchin) are expected later this year, initially involving Class 717 units. The Class 700 fleet is expected to begin migrating to ETCS on the ECML from 2027. The software upgrade of the Class 700 fleet will also help its readiness for future ETCS on the Brighton Main Line and Midland Main Line.
Aaron Meakin, GTR’s head of ERTMS Onboard, said: “As the only operator in the UK currently using ETCS version 3.6.0 in customer service, we’re pleased to build on our experience using digital signalling on the Northern City Line. We’re extremely proud of the teams delivering this testing, who worked extremely hard to ensure it was completed on time and safely in a very complex and critical environment, with minimal impact to our customers.”
Ricky Barsby, Network Rail’s ECDP Access Integration lead, said: “Getting the largest passenger fleet ready is a vital step in our preparations to gradually migrate to digital signalling on the East Coast Main Line. Having the new baseline level of ETCS in place for all fleets when they migrate will contribute to the resilience and high performance of the next generation railway.”
Richard Cooper, Infrastructure Lead and ECDP Project Director, Siemens Mobility UK&I, commented: “Building on the experience gained using digital signalling on the Northern City Line, this upgraded ETCS software on the Siemens-built Class 700 fleet will help deliver a more reliable, connected and sustainable railway for passenger and freight operators on the East Coast Main Line and beyond.”
Image credit: Govia Thameslink Railway



