Following on from the successful, world-first deployment of Automatic Train Operation (ATO) with the European Train Control System (ETCS) on the mainline railway in passenger service through the Thameslink core, the focus moves to the planned £1.8 billion East Coast main line (ECML) installation of ETCS.
Rail Engineer was invited to a Network Rail briefing describing how the LNE & East Midlands route, in conjunction with the Digital Railway, is going out to tender with a radical new approach for renewal of the train control systems on the ECML north from King’s Cross.
This event was hosted by Toufic Machnouk, route programme director LNE&EM, who explained that the intention is to achieve meaningful, feasible and sustained benefits that can be felt by passengers and freight users. The key ingredients of this will be closer working within the industry and a commitment from the supplier to maintain the product throughout its life, ensuring that everyone involved is immersed in the operational railway.
Furthermore, the Early Contractor Involvement programme (ECI), has established the need for contractor engagement starting very early in the development phase, looking closely at how technology can benefit the operational railway.
Phil Bennett, commercial director of the Digital Railway programme, elucidated the ‘design, build and maintain’ delivery model, which is very different to the way in which the industry has hitherto procured signalling, or indeed almost any activity.
ETCS is not a complete signalling system in its own right, but provides an interface between signalling trackside infrastructure and individual trains. The Driver-Machine Interface (DMI) in the driving cab displays the distance for which the train is authorised to travel, and the maximum speed allowed. If the onboard computer predicts that these values are likely to be exceeded, the system intervenes to safeguard operation of the train.
This functionality is termed Automatic Train Protection (ATP), providing continuous monitoring of the train. It therefore offers a higher level of safety than the current system-wide analogue Train Protection and Warning System (TPWS), which is not continuous, not provided at every signal, and not fail-safe.
At ETCS Level 2, the onboard equipment transmits and receives data from the signalling centre via the GSM-R radio network and the Radio Block Centre. Balises in the four-foot communicate with the train to provide position references. All other conventional signalling equipment is provided, including train detection, point-operating machines, interlocking, and signaller interface.
Lineside signals may or may not be provided, but retaining them allows trains to run on the route, whether or not they are fitted with ETCS. Not providing lineside signals, as on the Cambrian lines early deployment scheme, means than only trains with a healthy ETCS may operate on the line. Removing signals will reduce the resources otherwise needed to undertake signal faulting and maintenance on the line, although modern LED signals are generally maintenance free, compared with filament bulbs that require regular technician visits to check lamp voltages and replace faulty bulbs.
The important difference, compared with conventional multiple aspect signalling, is that braking distances are continuously re-calculated by the onboard European Vital Computer (EVC) in accordance with the movement authority (MA) received from the interlocking. To achieve an accurate stopping position, the driver will look out of the cab window and observe the physical location of the end of MA.
This is achieved by the provision of either conventional colour light signals (if fitted) and/or non-illuminated, reflectorised block markers. The positioning of block markers, unlike colour light signals, is not constrained by braking distance and, in conjunction with extra train detection sections, additional block markers may be provided to allow trains to close up, thereby increasing capacity.
The MA is continuously updated on the DMI, allowing the driver to accelerate immediately should conditions ahead improve, rather than having to wait for the next signal to come into view, thereby considerably improving performance and capacity.
ATO, if provided, adds a further layer of performance and capacity enhancement. Train operators’ professional driving policies are designed to reduce the signal passed at danger (SPAD) risk but this can also result in cautious braking on the approach to signals displaying caution and stop aspects.
Although the ETCS DMI provides the driver with a visual display of maximum permitted speed and target speed, controlling the actual speed and braking is still in the hands of the driver. Consistent driving, with actual braking that closely aligns with the calculated curve, will be achieved by the provision of ATO. ETCS is a pre-requisite for the adoption of ATO.
Today, the effectiveness of traffic regulation depends upon human intervention by signallers and train controllers adopting a proactive approach to reducing overall delay. This is where TM comes in – providing suitable tools to facilitate decision making that optimises the flow of traffic over a wide area, minimising delay minutes when there is perturbation and thereby ensuring the best outcomes for passengers and freight.
TM is not dependent upon having ETCS and may therefore now be deployed at any signalling centre. TM may be integrated with Automatic Route Setting (ARS) in order to optimise built-in regulating strategies, or it may just output recommendations for signallers.
Further optimisation of train regulation is achieved by giving live speed advice to train drivers, ensuring the trains arrive at points of conflict at the right time to avoid a capacity eating dead stand. This is achieved by linking TM to the Connected Driver Advice System (C-DAS).
Toufic Machnouk said the route is keen to exploit the benefits of TM at an early stage of the programme and, if it were to be deployed all the way to York and across the Pennines to Manchester, would bring substantial benefits.
The ETCS programme
The first installation of ETCS in the UK was in 2010 on the Cambrian lines in Wales, known as the early deployment scheme (EDS) and intended to be a lesson learning exercise. This was followed by the Thameslink core installation. The third installation of ETCS is on the short Heathrow airport spur and, when testing has been completed, will be used by the new Elizabeth line (Crossrail) Class 345 trains and Heathrow Express Class 387s.
ETCS is very expensive, and making a case for further installations has not been easy. However, at the southern end of the ECML, all the key factors are in phase, making one of most compelling cases to organise for the deployment of the digital railway in this area:
- Once in a generation renewal cycle;
- Signalling assets are nearing end of life;
- Physical constraints of a two-track mixed-traffic railway at Welwyn;
- Southern end of the ECML is operating at limits of timetabling capacity;
- Investment in new trains means 70 per cent of passenger trains come fitted with ETCS (new Hitachi and Siemens trains).
As can be seen from the box, the signalling between King’s Cross and Peterborough mostly dates from the Great Northern Suburban Electrification programme of the 1970s and is ready for total renewal, whilst the installations north thereof relate to the East Coast electrification scheme of around 1990.
Various life extension works have been carried out over the years, including the Peterborough station area interlocking renewal with Alstom MkIIa SSI in 2004, and complete refurbishment of the NX panel with new mosaic tiles supplied by Unipart Rail at Kings Cross in 2006/7.
Hence it is envisaged that provision of ETCS will align with renewal priorities, progressing north from King’s Cross and Moorgate to Peterborough North. This initial scheme will be a huge catalyst for renewals onwards to Doncaster and, beyond that, will naturally become ETCS with the progression of separate train fitment contracts. Continuity of work will ensure retention of knowledge as technical teams move from project to project.
Fundamentally different delivery model
In service, conventional signalling control systems utilise the skills of signallers, mobile operations managers, line controllers, maintenance technicians and engineers employed by Network Rail, working in the control centres and lineside. Maintenance and faulting of train-borne AWS/TPWS is a separate process involving staff from train operators and leasing companies.
With ETCS, more vital equipment associated with the safe movement of trains moves from the lineside into to the train itself. So, the organisational structure and roles will evolve with the process. For example, signallers and controllers will need to embrace traffic management techniques, drivers will need to learn in-cab signalling and signal technicians may need to gain synergy with rolling stock engineers.
The delivery model is depicted in the self-explanatory V diagram. Suppliers bid to satisfy customer outcomes rather than technical specifications. While the business case agreed with the DfT is based on ETCS Level 2 Baseline 3, the door is open for innovation, such as the additional flexibility that ETCS Level 3 hybrid would facilitate, but other options like this will only be considered if the technology is ready.
Approach and outcomes
This delivery model will be based on the following approach:
- Industry transformation programme bringing track and train closer together throughout programme and benefits cycle;
- Greater proximity in working between operators and technology providers;
- Based on industry concept of operations and asset management;
- Transfer of risk to private sector, which is best placed to manage it;
- Technology partnership procured on an outcome basis to support transformation throughout the lifecycle;
- Based on lessons learnt and best practices from multiple industries, UK and abroad.
- This is intended to bring about the following outcomes, for the benefit of passengers and customers:
- 20 per cent improvement in system capacity on a high performance, mixed traffic railway;
- Eight trains per hour (tph) provide a high performance, long distance high-speed services to and from Lincolnshire, Leeds, Newcastle, Scotland and the North East;
- Addition two commuter services per hour to relieve crowding;
- 20tph through the Welwyn two-track constraint;
- Route and network-wide catalyst – once ECML south is complete, all renewal further north will naturally be ETCS and significantly more efficient;
- Reduced delays to passengers through improved system reliability;
- Improved passenger safety from continuous automatic train protection and improved workforce safety by reducing maintenance requirement;
- Traffic Management providing plan/re-plan capability, enabling integration with stock and crew, and with C-DAS;
- Enabler for bringing track and train closer together.
125mph maximum speed
Intriguingly, missing from the list of outcomes is the ability to operate trains in excess of 125mph (200km/h). With the electrification of the ECML in the late 1980s, a new fleet of Class 91 locomotives was built with a capability of 140mph (225km/h).
To provide the additional braking distance required by the higher speed, an experiment was conducted in 1988 between Peterborough and Stoke Tunnel, deploying flashing green aspects which gave authority to exceed 125 mph. A steady green meant reduce speed to 125 mph. For all other trains, a flashing green had the same meaning as a steady green.
However, faster trains require a higher level of concentration in the driving cab. Test running revealed that 125 mph was the maximum speed at which a driver could safely observe a signal aspect, assimilate its meaning and act appropriately. Speeds above 125 mph would therefore require in-cab signalling.
Thirty years later, and ETCS is bringing that in-cab signalling to the ECML, but the world has moved on. Higher speeds mean fewer paths will be available on this mixed traffic railway for stopping and freight trains. While increasing capacity on the ECML is crucial to help meet the burgeoning demand, reducing the journey time by a few minutes may not be as important for passengers as it was in BR days, given today’s mobile connectivity with office, home, friends and family that was undreamt of in the 1980s.
Of course, high-speed rail is important for long distance journeys, but this role is migrating from the classic main lines to new, dedicated, purpose built, very high-speed routes such as HS2, leaving the existing network to provide more capacity and journey opportunities at intermediate towns and cities. Accordingly, speeds above 125 mph are not on the agenda for this phase of work on the ECML.
- The strategy is focussed around:
- Establishing long term collaborative partnerships (three for this scheme);
- Only by delivering outcomes do partners get rewarded;
- Bringing in supply chain partners very much earlier in the process;
- Establishing a longer-term relationship;
- Focussing on defining, delivering and thereafter maintaining support throughout the life of the assets of those solutions;
- Linking reward to those supply chain partners through those contract mechanisms to successfully achieve those outcomes.
In order to do this, Network Rail has moved to a different contract model and introduced NEC4, a widely recognised collaborative form of standard construction industry contract, in particular the ‘design, build, maintain’ model, contracting for the whole of the asset life. Bids to determine the successful supplier will be evaluated based on whole life provision of service.
To support the outcomes of a digital railway on the ECML, Network Rail Digital Railway is seeking to establish a single supplier framework agreement to deliver Digital Train Control Systems on the ECML from King’s Cross/Moorgate to Peterborough North. This framework agreement will include call-off contracts both for the outline design of the system and/or for the detailed design, build, supply and installation of the system together with ancillary conventional signalling, as required, to facilitate delivery of the digital system and long term (envisaged to be 30 years) maintenance of the system.
This train control partner (TCP) is expected to be selected in Spring 2019. Network Rail will call off packets of activity with the Moorgate branch forming one package, east coast south the second package and north of Peterborough the third package, all of which will be of 30 years duration. £1-1.8 billion is the anticipated aggregate value of the call-off over the thirty-year life, including long term service arrangement as well as physical delivery.
Two further partners are sought through separate contracts. A railway system integration partner, most likely a consultancy with experience in change management, will be appointed to provide services supporting the route client in managing cross-industry interfaces. Technical systems integration will remain the responsibility of the TCP.
In addition, a traffic management partner will be appointed for the procurement of traffic management systems from King’s Cross to Doncaster South. These TM systems will be required to interface with C-DAS.
So as not to disadvantage smaller suppliers, TM is a separate contract, as it is perceived that there are several small suppliers in this market place. For the TCP, bidders can be consortia, giving the opportunity for suppliers to come together.
A look to the future
Business cases are being worked up for the provision of ETCS to other routes including Anglia, TransPennine, Wessex and Western. The Castlefield corridor in Manchester is likely to receive early attention to address some of the pressing capacity issues there, following opening of the new Ordsall chord.
Converting the whole rail network to a digital train control platform is very much a long-term project, but the first big steps are now being taken to commence inter-city main line roll-out.