HomeDigital RailwayThe Digital Railway - a reappraisal

The Digital Railway – a reappraisal

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Much has been written on the Digital Railway project since it was initiated back in 2014. Not all of this has been complimentary, with critics believing the objectives to be overstated or even unattainable. However, the project is still very much ongoing and, with a new leader in place, a much greater degree of realism is being injected to ensure that the original goals can be maintained but re-assessed as to their priority and timeframe.

Rail Engineer spoke recently with Digital Railway’s managing director David Waboso, who has been in post since June 2016. David joined Network Rail from Transport for London where, as capital programmes director, he had been instrumental in getting much-needed new technology introduced to enable greater capacity to be achieved on the DLR, Victoria, Northern and Jubilee lines.

These projects were not easy to implement, with considerable disruption having to be endured, but much was learnt about how to deliver complex technology on busy operational lines. As such, David is a pragmatist and brings with him the experience of how to deploy new systems within a practical and logical plan.

Digital Railway objectives

It is perhaps timely to review the objectives for the digital railway. While the broader vision for the railway remains as originally defined, David has brought a much more pragmatic focus to the work of the Digital Railway programme. To drive capacity, performance and safety, focus is targeted on much-improved command and control technology covering ERTMS/ETCS, ATO (Automatic Train Operation), TMS (Traffic Management Systems), C-DAS (Connected Driver Advisory Systems) and, of course, telecoms.

This work links in with the broader industry goals of intelligent trains and infrastructure, leading to remote condition monitoring, smart meters on trains, energy supply resilience, and quicker and effective failure recovery situations. Improved passenger information and associated facilities are also in the mix, including ticketing, reservations, train running information accuracy and immediacy, train loading data, linkage to the internet and social media.

All these embrace the whole railway, not just Network Rail, and a fully integrated industry team is vital to eventual success. Key will be the participation of the Rail Delivery Group, the train operating companies including freight and, perhaps most important of all, the supply chain. With the latter, confidence has been low and the need for greater engagement is recognised.

Giving the Rail Supply Group and its many contractors greater accountability, with an enhanced relationship in the long-term projects, is part of the plan. Any scheme under the Digital Railway banner must contain, almost by definition, significant investment in software, and this has proved to be a troublesome element in the past. An important part of getting software right will be to properly specify the functional and operational requirements, “Don’t start writing code until you know what you want”, as David puts it.

So what are the main thrusts of the Digital Railway in terms of specific projects? There are no real surprises but there is now a much better recognition of what each element entails.

ETCS (European Train Control System)

To get more capacity and improved performance out of the existing railway is a cornerstone of the Digital Railway remit. This is not new but, given the increasing capacity crunch on key parts of the railway, the need is now urgent.

As a part of ERTMS, ETCS has proved to be a difficult concept at European level and dates back to the early 1990s. Conceived partly as political vision for Europe-wide interoperability, the technical and operational content has been a challenge to get common agreement amongst so many countries. At long last, a workable baseline specification has now been achieved.

Deployment plans in the UK, beyond the initial Cambrian line scheme from which valuable lessons have been learned, have included fitment to the GWML as part of Crossrail, and Thameslink. Dates predicted for when these are to become operational are now close and, when delivered, will form a strong basis to move forward.

The commitment to using ETCS on the Thameslink central core is already made, this being a route where capacity will need to match metro-type performance. Elsewhere, a long hard look at where and how ETCS and/or traffic management and CDAS/ATO can be introduced to get maximum benefit reveals eight potential routes: Great Eastern, Essex Thameside, East Coast, Great Western, South West main line, Southeast, East London line and TransPennine. The business cases for all these are still in development, but indications are that significant capacity and performance increases can be achieved without the need for major civil engineering expansion.

It must also be remembered that ETCS brings a safety benefit in that ATP (Automatic Train Protection) is part of the specification. Whilst TPWS has done a good job to mitigate against the SPAD risk, following the accidents at Southall and Ladbroke Grove in 1999 and the ensuing public enquiry, it was always recognised that this was not the long term solution.

The eight routes are an interesting mix of main line, long distance commuting and inner suburban railways. Some business cases will be worked up in partnership with the DfT and one – the East London line – will be progressed with TfL (Transport for London).

The capacity improvements to be gained will be different for each route as many other factors impact on what can be achieved; flat junctions, track layouts, level crossings, different station stops and mixed traffic patterns are typical of the constraints that differentiate a main line railway from a metro. The sometime-stated 40 per cent capacity improvement will very much depend on the layout and characteristics of each particular route and may very well be out of reach on many, but, nonetheless, any gain in double figures will be worth having.

Critically, any improvement will rely on a package of investment in both digital and conventional enhancements to maximise these benefits, which the programme believes will in some cases be cheaper than a purely conventional approach to increasing capacity.

Funding for all these deployments has yet to be agreed, so commissioning dates will not be published until this is known. The expectation is that the ETCS programme will form an important part of the solution to deliver increased capacity and reduce overcrowding as passenger numbers rise.

The idea of a pilot system in the Norwich – Yarmouth – Lowestoft area has been dropped. However, resignalling of this section is an urgent requirement and is to be achieved using modern signalling technology with ETCS future-proofing built in.

ETCS technology

Regular readers will be well aware that ETCS comes in three possible levels. Level 1 is a discontinuous train protection application not used in the UK. Level 2 is radio-based using GSM-R, retains traditional train detection equipment such as track circuits or axle counters, but can dispense with lineside signals.

Level 3 removes the need for separate train detection, relying solely on continuous radio messaging to report a train’s position while having the ability to introduce moving block whereby trains can ‘close up’ in congested areas. Part of Digital Railway’s original vision was to eventually move to Level 3, as this further improves the business case.

However, here in the UK as in Europe, a number of practical problems make adopting this on an existing railway very difficult and obtaining a safety case would be a lengthy process.

Thus it is a Level 2 application that will initially be progressed for the routes described. This is in line with what is happening in Europe and the suppliers are well acquainted with the technology. Even so, there are a number of options that need to be considered if a rapid deployment programme is to be achieved.

To remove lineside signals, every train, including on-track machines that operate over the line, must be equipped with ETCS equipment. This implies the need for captive stock, which is a limiting factor and will not be possible to guarantee on some sections without unnecessarily restricting the train service. The trade-off between large volumes of train fitment and retention of lineside signals will need careful consideration.

A mix and match solution will therefore be adopted that will allow much shorter block sections for ETCS-fitted trains working to a Movement Authority instruction and not necessarily obeying the traditional signals. Similar situations exist in Europe and, indeed, this is the Thameslink solution. It is envisaged that fitted trains will be dominant on any equipped route, thus obtaining the capacity benefit.

ATO as an overlay to ETCS is part of the Thameslink central core and is being pioneered here, with eyes from all over Europe watching how this progresses. Tests on the Hertford loop test track, and more recently in the Thameslink central core, are encouraging.

Level 3 is not to be entirely forgotten and a hybrid solution being developed in Europe to operate Level 3 characteristics over Level 2 infrastructure might be possible. This would retain existing train detection equipment and discrete block sections, but allow the creation of ‘micro blocks’ within these for Level 3-fitted trains. While this concept is still in the early stages, it is good that thought is being given to it.

Traffic Management Systems

When the ‘beauty parade’ of TMS systems and suppliers took place back in 2014, it was anticipated that this would be the start of a rapid roll out programme, giving much improved train regulation through pinch points and thus enhanced performance. Beyond the initial contracts let for Romford and Cardiff ROCs, and latterly at Three Bridges for the Thameslink central core, not much has happened, the reason being that it is a far more complicated application than originally thought. The capture of requirements, the staging and the integration with other systems, all has to be fully understood before any commissioning takes place. Otherwise the system will not perform and will be duly labelled as “another management waste of money” by the local staff.

All is not lost, however. Romford, Cardiff and Three Bridges are now making good progress and there is the possibility of one other being commissioned in the not too distant future. Once the usage and operational benefits can be established, the ‘domino effect’ rollout can begin.

TMS is part of the ROC deployment plan, but the planning/re-planning functionality is capable of being used in any modern day signalling centre, thus enabling its potential benefits to be put to good use in many areas of the railway in a more rapid timeframe.

Aligned with TMS is C-DAS, which will communicate relevant parts of the decision making process of TMS to the driver in the cab. Without the connectivity that C-DAS brings, the use of standalone DAS is limited as it can only give drivers advice on the train’s optimum speed for the particular journey based on the timetable – it takes no account of the effect of other trains at forthcoming stations and pinch points which may require trains to operate to a more updated train plan.


David knows full well that a digital railway needs a reliable, modern and resilient digital telecoms network for it to succeed. Fortunately, Network Rail is in possession of one such network, namely the FTNx of NRT (Network Rail Telecoms), and this therefore becomes a big part of the Digital Railway group. Recent suggestions that NRT might be sold off in order to make a ‘quick buck’ have now been rejected as it is realised that telecoms is a vital part of the operational railway. To lose the in-house capability would be akin to committing industrial suicide. The sad lessons of the earlier BRT sell off must never be forgotten.

That said, the exploitation by NRT of its asset has to be encouraged as valuable income can be gained by providing bandwidth and services to other organisations, especially in rural areas.

Digital showcase

There is no doubt that the Digital Railway is alive and kicking. This article has not said much about the asset management and information services that are all part of the plan. Rest assured, these are progressing in parallel and are already underway. Not quite as newsworthy as the command and control elements, they are easier to achieve and rely on standard IT technology as used in many other industries.

Technology itself is a challenge, as the rapid advancement of digital systems can mean that applications even five years old may begin to look out of date. The solution to this is much greater industry involvement with a whole life contractual formula in place that will enable hardware and software updates to happen as technology obsolescence necessitates replacement.

The recent government announcement of an additional £450 million of funding is indicative as to how seriously it takes the digital railway programme and the need to obtain the benefits in the quickest possible timescale.

David’s parting words were: “Britain was at the forefront of railway development, it had the first metro in the world, it introduced the first automatic train operation, it needs to be the showcase for the digital railway revolution.”

Amen to all of that.

Written by Clive Kessell


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