Signalling and Telecoms or, more appropriately these days, Control and Communications (C&C), continues to be a controversial subject with regard to where the future lies. Separately in this edition, the head of C&C in Network Rail gives a frank appraisal as to the way forward and the difficult choices that must be made. Many other commentators and experts have expressed views as to the options on offer and the Railway Industry Association (RIA) recently organised a gathering of its Member Interest Group to put forward various factors that might focus attention.
Network Rail considerations
Darren Jowett, Network Rail’s head of systems authority, painted a picture where S&T can no longer be considered a separate entity, but where the whole C&C scenario will be influenced by other technologies that contribute to the reliable operation of train services. Much of this will be part of the overall digital railway initiative where the body known as the Digital Railway System Authority will be working to standardise requirements and specifications. Part of this will be to produce a deployment of design that leads to a baseline of requirements that can be delivered to the real railway.
This sounds grand but in essence it will be a combination and updating of all the existing standards that are used for effective train control and operation covering the various technical disciplines that exist for infrastructure and rolling stock. This will then provide a cross-industry technical leadership for a systems approach to future C&C strategy. An enabler will be the Requirements Issue Configuration Management Group (RICMG) populated by expertise within the different disciplines. Support and communication to industry must be part of the process.
The European Train Control System (ETCS) is expected to be part of the way forward and despite the long drawn out process to get this confidently established as a mainstay of future train control, different routes were suggested as to where ETCS will be deployed after the East Coast Main Line ECDP project. The northern section of the West Coast Main Line, the Midland Main Line, and the Brighton Line are all part of the vision. However, it is admitted that ETCS is currently proving to be way too expensive and a means of reducing the cost are urgently needed.
The ultimate goal is to have no lineside signals and no traditional train detection systems. That is a tall order and impacts heavily on the continuance of safety standards so another panel – the System of Systems Safety & Security Panel (4SP) – will be there to ensure track and train equipment can be safely introduced.
Authorisation from the Office of Road & Rail (ORR) will be a necessary part of the process. While it has taken a long time to get ETCS software finalised as internationally accepted standards, no one is pretending that these will remain the same for all time, and updates to software will be an ongoing challenge. The configuration management process for ETCS follows the pattern: Baseline – Status – Change Control – New Status. With any new software, it is expected that any existing onboard train equipment will be backward compatible to new train software; however, it is much more difficult for new infrastructure software to remain compatible with existing train software. These are challenges that must be recognised and resolved before a major deployment of ETCS can take place.
Train protection
Protecting trains from occasional lapses of driver concentration has been a concern for railways for decades. Sometimes it takes a serious accident to trigger improvements, and this happened with Harrow in 1952 which, with 112 people killed, led to the adoption of AWS. More recently, accidents at Southall and Westbourne Park where many people lost their lives, prompted an enquiry into train protection systems and, from this, the go ahead was given for the adoption of the Train Protection and Warning System (TPWS). The fitment of TPWS loops at the highest risk locations has been completed, which has virtually eliminated the risk of Signal Passed At Danger (SPAD) occurring. However, TPWS was always seen as a pre-runner to ETCS which would provide complete train protection on all the routes where it exists. Perhaps inevitably, the success of TPWS has worsened the business case for ETCS progression at least in terms of train protection, but that can sometimes happen.
More recently, a new threat has become prominent, which is over speeding. Several significant incidents have occurred where drivers have misread signals and accelerated swiftly towards a slower speed diverging route. There is no one cause for this, but two factors emerge: the sometimes-long distances between the controlling signal and the diverging points, and the high acceleration rate of modern electric trains. In one incident, the train came within a whisker of overturning.
To investigate and minimise this risk, Darren explained that this is entrusted to the Train Protection Steering Group. Informing drivers of speed restrictions is still paper based and nothing much has changed in 100 years. Being provided with a daily notice at a signing in depot or delivery of the same online, takes little account of the ability of the human brain to remember it all. Temporary speed restrictions are typical examples of where the information is either forgotten or mis-interpreted and instances where trains have entered a speed restriction at more than twice the required speed are not that rare.
The TPSG is progressing four phases of work:
- Understanding the problem.
- Speed Management System development concept and proving it.
- Design of systems recognising that no one size fits all conditions.
- Operational trial.
- Driver advisory systems.
One possible technical solution is to adapt Driver Advisory System (DAS) information to provide drivers with a near continuous update as to speed conditions. Up until now, DAS applications have primarily been aimed at energy savings by advising the driver to progress at a speed that minimises energy consumption. As such, DAS is not regarded as a safety system.
The introduction and usage of DAS and so-called Connected DAS (C-DAS) has been fragmented and different TOCs have introduced systems from different suppliers with no standardisation either in the technology or the display to the driver. The connectivity of C-DAS systems is also debatable, but all fall short of a total solution that would have to link with Traffic Management Systems. These too are in their infancy and again with no standardised interoperable specification.
Thus, to use DAS for giving drivers continuous speed information and to link this into some kind of interface to the braking system if over speeding occurs would almost certainly mean raising DAS up the safety level rating and producing specifications that produce a level of standardisation. That is no mean task.
Cyber security and ETCS
Cyber security often features in Rail Engineer. Dr. Richard Thomas from AtkinsRéalis gave a generic update and explained the focus for the ECML adoption of ETCS. Safety is usually a static situation once a system is in operation, but cyber security is a dynamic process that has to be constantly monitored during an asset life which could be 30-50 years. Cyber security has massive and growing numbers of regulations associated with it which must be followed by the supply chain, the users, and the maintainers. An article by Paul Darlington in Issue 219 (March-April 2026) described many of them.
It was a six stage process to progress the Northern City Line (NCL) from Drayton Park to Moorgate to achieve cyber assurance while still retaining lineside signals: (i) define the system; (ii) risk assess the trackside, rolling stock, and dependencies; (iii) define proportionate requirements and controls; (iv) review supplier evidence and compliance; (v) build the security case; and (vi) commission the system.
It took a further four stages before signals could be removed: (i) review the risk assessment in the new context; (ii) engage with partners to assess evidence; (iii) update the security case; and (iv) remove the signals and commission the new railway configuration.
This process will be adopted as a template for the forthcoming introduction of ETCS from Welwyn to Hitchin. As such there needs to be a generic approach followed by work on any specific application. The basic rule is to assess early and build the support network around it. There is a need to demonstrate the process to the wider world where industry should have an informed position to support ongoing applications and projects. Cyber-attacks do happen and there is evidence that ETCS systems in operation have been targeted.
Progressing the ECDP
As a follow on from this, Andy Ward, ECDP programme engineering manager at AtkinsRéalis, informed the gathering that a different assurance framework for a railway being converted to ETCS is needed compared to how signalling projects have been assured in the past. To introduce ETCS on any route requires significant integration and continuous interactions between all organisations involved, be it operational or technical, and the duty holders. These include the Network Rail Route management, the TOCs, and the suppliers.
The apportionment of technology is changing with much more of the signalling equipment on board the trains. The process being followed for the ECDP is: (i) safety; (ii) security; (iii) reliability; (iv) capability; (v) operational readiness; and (vi) maintainability readiness. Teething problems have been experienced on the NCL, but this was a relatively simple piece of railway with only one type of train. Much more challenging is the Welwyn to Hitchin section.
Concluding thoughts
This was an interesting session and, while intended to give an upbeat message as to ETCS progression, it is recognised that the system is currently regarded as costing too much with further deployment on suggested routes far from certain. Of the lines equipped so far – Cambrian, Thameslink central core, GW main line to Heathrow Airport – one might sense that the NCL and Thameslink are very similar railways (intense suburban service mainly in tunnels) as indeed are the GW route and Welwyn to Hitchin section, at least while lineside signals are retained. What processes were used to verify and assure the Thameslink and GW system operations? The only real difference on ECDP is the use of packet switching for the radio connection. One gets the uneasy feeling that the assurance process is being invented again for ECDP. It will be up to Network Rail to set the generic standards for ETCS introduction elsewhere and to ensure these are applied as almost a tick box exercise which could be done in house.
One must also remember that the radio connection is a vital part of successful ETCS operation. This is currently GSM-R, a 2G technology, and while Darren referred to its replacement with FRMCS, a 5G technology, this writer has serious concerns that Network Rail underestimates the scale, complexity, and cost of the upgrade and changeover.
Mention was made that negotiations are taking place for continuance of GSM-R until 2040 but this could be a dangerous premise since it needs the supply industry to guarantee equipment availability at a reasonable price. Speeding up the FRMCS roll out might be a better policy. There could be advantages of delaying further ETCS projects until the new radio system is deployed in the projected ETCS route areas so as to have a modern and proven radio connectivity in place once ETCS is progressed.
This was a very interesting event. When coupled with other recent information from Network Rail, it is clear that many re-signalling projects in the near future will have to use traditional technology as the need for replacing worn out and obsolete equipment does not match the rate at which ETCS can be deployed.
Looking back at the articles that have been written over the past 10-15 years, the roll out of ETCS was predicted to be commissioned on many main lines by the mid-2020s. However, that has not happened and the reasons are all too obvious, many of which still require some resolution. Couple all this with FRMCS, DAS, and TMS, it is going to be interesting to see how GBR moves forward with these challenges and whether a directing mind is appointed to lead the way.
