Successful high‑speed testing of upgraded digital signalling software has been completed on a Thameslink Class 700 unit, marking a major milestone in preparing the largest passenger fleet on the East Coast Main Line (ECML) for in‑cab digital signalling.
The 115‑strong Thameslink Class 700 fleet forms the biggest passenger element of the Government‑funded £1.4 billion East Coast Digital Programme (ECDP). The programme will modernise rail operations by replacing traditional lineside signals with continuous, real‑time information displayed inside drivers’ cabs, supporting a more reliable, greener and safer railway.
Testing took place over two Sunday evenings in April and May within the central London Thameslink ‘core’ — between London Bridge and London St Pancras. A GTR Class 700 train operated using European Train Control System (ETCS) version 3.6.0, an upgraded baseline of digital signalling software. The work was meticulously planned to ensure no impact on the start of passenger services at 4.30am on Monday mornings.
Govia Thameslink Railway (GTR) is currently the only train operator in the UK running ETCS version 3.6.0 in passenger service, following its successful deployment on the Class 717 fleet on the Northern City Line. The latest testing, carried out in close collaboration with Network Rail and Siemens Mobility, focused on confirming that all existing train functions continued to operate normally alongside the enhanced ETCS capability.
The upgraded software enables greater operational flexibility in high‑traffic corridors such as the ECML by connecting trains to trackside systems via GPRS packet‑switched communications, supporting more resilient and responsive railway operations.
The first passenger services on the ECML to operate with ETCS — between Welwyn Garden City and Hitchin — are expected later this year, initially using Class 717 units. Migration of the Thameslink Class 700 fleet to ETCS on the ECML is planned from 2027. The software upgrade also strengthens the fleet’s readiness for future ETCS deployment on both the Brighton Main Line and the 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, said:
"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: Network Rail
