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HS2 cutback update

The only parts of HS2 now certain to be built are from Old Oak Common to Birmingham and Handsacre Junction on the West Coast Main Line (WCML). When announcing his decision to cancel HS2 phase 2 and replace it with Network North, Prime Minister Sunak gave an assurance that HS2 would terminate at Euston. However, it now seems that this promise depends on securing sufficient private investment.

Curtailing HS2 was a decision of huge magnitude. The HS2 Y network from London to Manchester and Leeds, and its trains, were designed as a fully integrated system. Hence permanently curtailing the network to its trunk line has significant adverse consequences.

These consequences are now becoming clearer, partly from the Parliamentary Transport Committee (PTC)’s HS2 update session on 8 November, when witnesses included Andrew McNaughton (AMcN), HS2’s chief engineer then technical director from 2012 to 2018, and Richard Bowker (RB) who was CEO of the Strategic Rail Authority which rescued the West Coast Route Modernisation project.

Capacity

Part of the case for curtailing HS2 was passenger numbers not returning to their 2019 pre-Covid levels. Yet the 1.4 billion rail passenger journeys in 2022/23 were 10% more than those in 2009/10 when HS2 was initiated. At the PTC, RB advised that, on the West Coast Main Line (WCML), Virgin trains passenger numbers increased from 11 million to 40 million in the 20 years since 1997.

AMcN noted when HS2 was initiated, the WCML was expected to run out of capacity in the mid-2020s. Though Covid was a shock, against an underlying long term trend, its effect is delaying WCML running out of capacity to 2030.

RB advised that, between Lichfield and Crewe, WCML is already at capacity with 13 train paths: Manchester (3); Liverpool (2); Preston & Glasgow (2); Chester (1); West Midlands Trains (1); and Freight (4). HS2 phase 2a from Handsacre Junction to Crewe would have by-passed this section to allow more trains to run, particularly freight trains. It would have also offered more trains on the Manchester to Birmingham corridor.

Network North: Transforming Briitish Transport

HS2’s train frequency is determined by the capacity of its London terminal station. RB advised that Old Oak Common could reliably operate six to eight trains per hour and that the current plan is for seven trains per hour. He considered a lot of people would be penalised if this became HS2’s London terminus.

Both RB and AMcN considered that a six-platform HS2 Euston station could operate 10 trains per hour provided that there was grade separation between departing and arriving trains. AMcN considered that, to ensure a reliable service, there should be a seventh platform to accommodate any failed trains.

In his statement to Parliament about the HS2 cutback, Transport Minister Mark Harper claimed that HS2 phase 1 will still deliver a massive increase in capacity to the WCML by increasing the number of seats a day from 134,000 to 250,000, despite no additional WCML capacity being provided north of Handsacre junction. The table below uses the information in RB’s evidence to the PTC to estimate that HS2 phase 1 from Euston offers a 49% overall increase in seat capacity, with a 153% capacity increase on services to Birmingham, whilst the northern cities will get little from HS2.

Rail Engineer asked the DfT press desk to supply the assumptions and calculations from which their estimate that HS2 phase 1 will increase the seat capacity of the HS2 / West Coast long-distance operator by 86% was derived.

Its response was that: “We estimate capacity will nearly double between London and Birmingham and there could be up to 250,000 seats per day along the West Coast Main Line and HS2 combined,” and, without any explanation, it advised that the underlying calculations are internal estimates which cannot be supplied.

As shown above, the DfT is right to state that Birmingham will benefit from a huge increase in connectivity with the capital, yet with no plans to increase WCML capacity north of Handsacre it is unrealistic to consider that HS2 phase 1 will provide the WCML as a whole with an 86% capacity increase. The DfT’s refusal to explain how this estimate was derived further detracts from its credibility.

Thus, it would seem that Harper was wrong to advise Parliament that HS2 phase 1 offers “a massive increase in capacity to the WCML” as it offers little capacity north of Handsacre Junction. When PTC chair, Iain Stewart, asked him what is to be done to relieve the severe WCML capacity constraint north of Handsacre junction, he failed to answer this specific point. Indeed, when Harper appeared before the PTC on 15 November, he advised that there was no such capacity problem.

Freight

WCML is used by 40% of the UK’s rail freight. With the cancellation of HS2, there are now no plans to increase the current four freight paths per hour on the WCML north of Lichfield. In its statement, the Rail Freight Group (RFG) “condemned Government’s decision to cancel HS2 construction north of Birmingham describing it as the worst possible outcome for rail freight.”

RFG director general, Maggie Simpson said: “Scrapping HS2 whilst still allowing its trains to run on the existing network is the worst of all possible decisions. The West Coast Main Line simply does not have the capacity for these extra trains alongside current services,” and that investment will now be required to ensure all trains can be accommodated.

The RFG statement noted the recent significant investment in new strategic rail freight facilities to support WCML rail freight growth which HS2 would have provided. Cutting back HS2 is both a blow to those investors and those who wish for fewer HGVs on the nation’s roads.

Business case

In October, the DfT’s accounting officer advised that the Benefit Cost Ratio (BCR) of only building HS2 phase 1 was 1.1 to 1.8, excluding money already spent. This assessment showed that only building phase 1 reduced its value for money as it only offered eight trains per hour (tph), rather than the 17 tph offered by phase 2. The BCR for the phase 2 schemes was not calculated as it was not normal practice to assess cancelled schemes.

At its last published cost of £44.6 billion, the 224km HS2 phase 1 route costs 200 million per km. The 60km HS2 phase 2a route was estimated to cost between £5.2 to £7.2 billion which is about £100 million per km. Phase 2a did not require expensive tunnelling so is half the cost of phase 1 and could have doubled the number of its train paths.

Not surprisingly, at the PTC, RB considered that HS2 phase 2a must have a high BCR as it would free up paths for more freight and passenger services as well as giving HS2 trains an additional 13 minute journey time saving.

AMcN advised that he would be astonished if there was an economic case for HS2 phase 1 on its own. He noted that, since 2009, HS2 considered that there was no point of HS2 just going to Birmingham as this had to be considered as the start of something that was to open up northern cities.

RB made a heartfelt appeal to Government to reconsider HS2 phase 2a as, for relatively little additional cost, it offered transformational benefits and would make best use of the money spent on phase 1. He noted that phase 2a would have provided game changing improved connectivity between cities in northern England. For example, Birmingham to Manchester in 42 minutes instead of the current 90 minutes.

The PTC considered alternatives that might provide the same capacity as HS2 phase 2a, the cost of which should have been considered as part of the decision to cut back HS2. RB advised that something similar to the massively disruptive £10 billion WCML route modernisation would be required, though this would not offer the same benefits as HS2.

Handsacre Junction options

One particular issue is Handsacre Junction which was originally designed to transfer HS2 trains directly onto the WCML’s centre fast lines to minimise their capacity impact. This required an expensive 1.9km diversion of the WCML Up slow and fast lines. The decision to accelerate phase 2a’s construction meant that few HS2 trains would use the junction, hence the junction was redesigned to reduce costs with HS2 lines joining the WCML slow lines.

With the cancellation of phase 2a, the junction will now be constructed as originally designed with HS2 joining the WCML fast lines. This is a further aspect of cancelling phase 2a that will involve significant additional costs. Moreover, as the HS2 phase 2a Act now specifies a slow line connection, there are no longer Parliamentary powers to construct the original junction connecting HS2 to the WCML fast lines.

Business impact

When asked about the impact on business of HS2’s curtailment, AMcN advised that the scale of this is pretty big as hundreds of SMEs are involved with HS2’s infrastructure and trains. He mentioned that the company leaders he had met expressed genuine shock at the impact of the HS2 decision and that this will reduce the number of apprenticeships. Another witness observed that the HS2 decision creates business uncertainty which makes projects more expensive and discourages apprenticeships.

The decision to transfer the project management of Euston station from HS2 to a development company adds further uncertainty as HS2 let a £1.6 billion contract for construction of Euston Station in 2019. Government recently declined to confirm whether these contracts will still be valid under its new Euston station plans.

It has also been reported that Alstom is to make 600 of its 2,000 people redundant at its Derby works which is to have had a key role building 54 trains for HS2. Alstom now expects fewer trains will be required and is now seeking clarity in this respect. Whilst this is likely to be a factor in Alstom’s decision to impose redundancies, a bigger issue is there being no significant new train orders since December 2019.

It is worth noting that a significant factor in the growth of the Alstom and Siemens rail business was the demand for their high-speed trains due to the construction of the French and German high-speed networks over 25 years ago.

Euston

Although the Prime Minister’s announcement stated HS2 would terminate at Euston, the following day the BBC reported that unless sufficient private finance is raised, HS2 will terminate at Old Oak Common (OOC).

AMcN noted that, with over four designs for HS2’s Euston station, over £100 million of design work had been wasted. In his view, this was a case study of how not to do things. He wondered if Government understood the implications of specifying an over station development. In his experience, few of the world’s cities build on top of their stations as this presented significant additional engineering challenges. He felt that this was a key reason for its excessive cost.

Constructing the 7.2km tunnels between OOC and Euston is part of a contract let to Skanska Costain STRABAG in 2017 as part of the Main Works Civils (Area South) package. Recently, Skanska advised that their two tunnel boring machines will complete the tunnels to Euston in 2028.

HS2 Euston Station site, August 2022.

In respect of Euston, the DfT advised Rail Engineer that “the Government will continue to comprehensively engage with the private sector and the existing HS2 supply chain to work to deliver this project, creating a transformative Euston quarter with as many as 10,000 new homes and opportunities for businesses to thrive” and that this uses a similar approach to the successful regeneration of King’s Cross and the Battersea and Nine Elms development which included the Northern Line extension.

At the PTC, RB stressed that the primary function of HS2 Euston is as a railway station and was concerned that involving private finance could increase cost.

Costs

Not surprisingly the PTC expressed concern about HS2’s costs. AMcN considered that the scheme that went into bill was accurately costed as it was designed by the people who designed HS1 which was delivered to budget with similar complexity to HS2. He felt that HS2 was no different to any other infrastructure project in that all suffered from the materials, energy, and other cost increases.

He advised that, after Carillion went into administration, the supply chain became nervous about risk. On HS2, the Client has given a lot of risk to the contractor who then provided costly over-engineered ‘bomb proof’ designs to insure themselves against this risk. He observed that whilst there were lots of white collar people, the UK was not well blessed with artisans who create projects which is, in part, due to the stop-start nature of government funded projects. Hence there needs to be greater emphasis on standard construction that does not need so many skilled people.

He also noted that the client needs to know what they want and stick to it. He noted that “every change is Christmas for supply chain.” Hence clients must avoid changes in scope. RB considered that when projects get into difficulty, it is important to consider how the client specifies and manages the project.

AMcN accepted that costs had increased due to poor ground condition data as sometimes it had not been possible to access land for surveys. He considered that this was one reason for cost escalation, though it was not the principal reason.

When questioned whether HS2 phase 1’s design had changed since its Bill became an Act AMcN confirmed it had not and that he did not have a clue what had changed to increase costs since then.

He advised that from day 1, HS2 had been designed for maximum capacity in accordance with its remit. This increased costs as it required more tunnels to minimise public impact from an intensive service. Slab track was also chosen because of the high cumulative load. He insisted that the incremental cost of high speed is marginal and that it “simply was not the case that speed affected alignment.”

AMcN also noted that DfT studies had shown that enhancing the existing network to increase capacity comparable to HS2 would cost more with huge disruption requiring lines to be continuously shut at weekends for years. This would also significantly affect those adjacent to the line as existing railways run through towns that have grown along the railway.

No strategy

HS2 was born out of a highly detailed 2008 Network Rail study that considered the long-term need for rail capacity which concluded that the WCML needed to be relieved by a high-speed line. HS2 then developed proposals for a Y-shaped network serving eight of the UK’s 10 largest cities which were then subject to intense Parliamentary scrutiny. For around 15-years this has been the strategy for providing much-needed rail capacity on which Network Rail and northern cities authorities have based their planning assumptions.

This strategy changed with the publication of the Integrated Rail Plan (IRP) in November 2021. Although this terminated HS2’s eastern leg at East Midlands Parkway, HS2 was still a major part of IRP which proposed that part of Northern Powerhouse Rail (NPR) would use its western leg to Manchester. With the curtailment of HS2, IRP lost its backbone and so ceased to be a strategy. NPR also lost part of its proposed Liverpool to Manchester line.

HS2 phase 2 has been replaced by the collection of diverse, largely undeveloped, projects that is Network North. In contrast to the expertise and time taken to develop HS2’s Y network, Network North was hastily produced without consulting Network Rail or other key bodies including the National Infrastructure Commission whose chairman, Sir John Armitt told the RIA conference that he considered the Network North document to be “a bucket full of projects” that was not a cohesive plan.

At the PTC, RB expressed similar concerns about Network North. He agreed that it contained some worthwhile projects such as the Ely capacity enhancement which would provide extra freight train paths. Yet the WCML won’t be able to accommodate any such additional freight traffic.

Network North also includes 70 road upgrades and allocates billions of pounds to repair potholes, so is a significant transfer of funding from rail to roads. For example, the Government claims that its “£8 billion boost to repair roads and back drivers” is redirected HS2 funding. Yet this is not true as HS2 was a profitable capital investment that was to be funded by borrowing, whereas the cost of road repairs is operational expenditure.

Thus, the Prime Minister’s October announcement not only cancelled HS2 phase 2 but left the UK without a strategy to increase rail capacity. Moreover, the decision to sell land acquired for HS2 makes it difficult for any future government to develop such a strategy.

In the last 25 years, the number of cars on Britain’s roads has increased from 22 million to 32 million. Instead of adding to the road load, modal shift to rail is needed to reduce transport carbon and provide the connectivity that northern cities need to boost their economies. As Richard Bowker noted, if the nation seriously wishes to address these issues, a strategy to increase rail capacity will be needed. For the UK’s northern cities, any future strategy is unlikely to be much different to the one on which hundreds of millions of pounds has been spent over many years whilst it was developed subject to intense Parliamentary scrutiny, namely HS2 phase 2. Hence the decision to sell off land acquired for HS2 prevents any meaningful plans to increase rail capacity. It is also inexplicable why the decision has been taken not to construct the 58km HS2 phase 2a line which would hugely increase the benefits from phase 1.

Gripple – Swiftline Rail Dropper

In its final determination of Network Rail’s funding for Control Period 7 (2024-2029) (CP7), the Office of Rail and Road (ORR) says Network Rail must continue its efficiency initiatives to deliver the ambitious CP7 plan, and to deliver the best value within the available funding for CP7. The ORR also says the efficiency target of at least £3.2 billion is stretching and realistic. Network Rail has therefore set itself a renewal (capital expenditure) target of 15% and says the supply chain is key to delivery of this target. This will require challenging how everything is done and finding new suppliers and new ways of doing things.

This must be done carefully though, and there are many examples of the rail industry using suppliers and items new to rail that, while initially appearing to offer advantages and cost savings, eventually failed to offer the anticipated benefits. This is why the Product Approval process is required. The approval process can be lengthy and appear bureaucratic, and put some suppliers off, but a good example of something new which has recently been approved and offers great benefits is the Gripple SwiftLine Rail Dropper for Overhead Line Equipment (OLE).

OLE dropper

In rail electrification, the OLE dropper hangs vertically from the catenary at regular intervals. The catenary is the longitudinal wire which supports the contact wire via the droppers. The contact wire carries the electric current to the train via a train’s pantograph.

OLE maintenance possession windows are never long enough. So Gripple’s innovation team used its considerable experience with mechanical suspended solutions, and collaborated closely with rail OLE engineers and contractors, to develop the game changing SwiftLine Rail Dropper. This has been designed to be faster, safer, and easier to install than conventional OLE droppers. The dropper is supplied pre-cut and ready to go, therefore it can be installed quicker with no cutting or measuring required on site. The easy to use, plug and play, tool free design delivers a faster installation and offers reduced safety risk with less time working at height in the dark, which is when most of this work usually takes place.

The SwiftLine Rail Dropper can be fully installed up to eight times faster than traditional cable droppers and can then be adjusted left and right along the wire in seconds, using the lockable release cams, rapidly increasing the speed and efficiency of installation and repairs.

Gripple AutoTorque Contact Clamp Fixing

Gripple

Gripple is a manufacturer of wire joiners and tensioners used for construction suspension, catenary systems, trellising, and civil engineering as well as various engineered solutions for other infrastructure applications. The company employs over 1,000 people in 15 global locations and manufactures across seven sites in Sheffield, South Yorkshire.

The company was named Manufacturer of the Year at the Manufacturer MX Awards (TMMX) in 2022. Featuring 50 of Britain’s top manufacturing companies, the Awards encourage, benchmark, and celebrate manufacturing excellence. Gripple also came away with further awards, including Young Manufacturer of the Year 2022.

With additional manufacturing and sales hubs located in Chicago, Obernai, Warsaw, Toronto, New Delhi, and Kobe, Gripple is a 100% employee-owned company, with a strong focus on investing in people, innovation, and sustainable growth. In 2011, GLIDE was established, which is an employee-owned company representing employee owners at Gripple and its partner companies, Loadhog and GoTools. Founder and chair, Hugh Facey OBE, alongside vice Chair, Roger Hall, agreed to donate a significant portion of their shares into GLIDE, as part of the process of passing the company to the employees. Employee-owned through a direct ownership model, every employee is required to buy a minimum of £1,000 worth of shares after a year in the business.

GLIDE’s elected board of representatives have a number of core objectives; to protect and enhance the culture, to be custodians of GLIDE’s gifted shares, and decide on the best way to share dividend income with members, and to challenge the businesses in line with key performance principles, e.g. targeting sustainable business growth through innovation in new products and new markets. Employee owners are empowered to take responsibility for the business, to challenge and to ask questions, and ensure the business sustains for the long term benefit of current and future generations, and its customers.

Rail dropper development

Gripple had previous experience of working in the rail industry when it had used its ground anchors solution as a method of stabilising embankments. While working on these projects, it noticed many similarities between the problems OLE installers were having and problems it had already solved in the building services sector. When attending site, it could see the issues with OLE droppers and identified that Network Rail was also looking for a solution.

Gripple started to investigate whether its technology could benefit OLE installations, in the same way it had done for catenary suspension in the other markets. Gripple’s findings gave confidence that it could improve how rail droppers were installed and make the process much quicker, safer, and more efficient.

The University of Sheffield, a part of the UK Rail Innovation Network (UKRIIN) was approached to find out more about the rail industry’s challenges with electrification. This and other research, confirmed that installing rail droppers was one of the most time-consuming aspects of a rail project and one of the reasons that electrification rollout had been slow.

Nine design engineers brainstormed ideas and produced 20 concept ideas and drawings. These early concept ideas were presented to a group of industry experts, consisting of Network Rail employees, OLE contractors, and consultants. This allowed Gripple to design a product to meet Network Rail’s needs. The three concepts were selected to be carried forward and developed.

While developing the solution, regular meetings with rail industry stakeholders were organised to ensure the solution was steered in the right direction, based on the user requirements. Using their in-house 3D printers, Gripple was able to incorporate the feedback into the development and allow stakeholders to get ‘hands-on’ with the 3D printed prototypes of the product as the design progressed.

As further development took place, regular feedback was sought from OHL rail engineers and contractors. Once everyone was happy, a ‘concept freeze’ was initiated and the chosen concept was taken into the detailed design stage, allowing Gripple to work alongside Network Rail to ‘fine tune’ the product. This would ensure the product was as beneficial as possible for the customer and efficient to manufacture.

Challenges

One design challenge was the contact clamp torque. Historically, installers had experienced problems with the contact clamp not being set to the correct torque, as it had to be installed and set manually using a nut and bolt and hand tools to provide the clamping force. This was susceptible to user error. To address this Gripple developed their auto-torque contact clamp to guarantee ‘right first-time installation. This uses a lever which provides a pre-set clamping force so that the right torque was guaranteed every time.

Another challenge was to improve the speed of installations while still creating a fully conductive product. The design engineers developed the Gripple Volt Lock system, which is housed within the catenary wire top dropper and includes a roller which both grips the dropper wire and ensures constant contact with the copper housing of the product. This makes the product fully conductive.

Production

Once the final product design was agreed, Gripple made a business decision to invest and put the dropper into production. Product managers and product designers worked with the dedicated new product implementation team, which co-ordinated the production and launch with other departments within the company.

The next stage of product development was to identify the machinery and tools to produce the product, and develop plans for manufacturing and conduct trials. The operations teams undertook pilot build and packing trials, as well as finalising the production and manufacturing processes. Product managers tested the dropper product in a real-world environment at a Network Rail sites.

Once this was completed satisfactorily, the innovation team and new product implementation team handed the product designs over to production. The Norfolk Bridge Works in Sheffield was selected to carry out the bulk of the production as it had the largest capacity. Punch and press brake tools were both already in operation at the site to produce Gripple products already used in the construction industry. This meant that existing processes could be adapted to produce the SwiftLine Rail Dropper, rather than waiting for the delivery of completely new machinery.

Final assembly would then take place at Gripple Head Office at the Old West Gun Works in Sheffield. The Norfolk Bridge Works opened in 2021 as a modern manufacturing facility and features 442 solar panels, a green living wall, as well as a smart building management system. The Old West Gun Works became the Gripple headquarters in 1994 and the iconic building now houses wire rope and sling manufacture, packing and distribution, as well as IT, finance, supply chain, and people & culture teams.

‘Vertical integration’ is a key driver at Gripple and the company aims to manufacture and control as much as possible in-house. This includes the machines that produce products and gives Gripple greater control over their supply chain, helping to provide continuity to customers and protecting from external supply pressures.

For the SwiftLine Rail Dropper, Gripple worked with its sister company GoTools, which specialises in precision tooling and machinery. GoTools was able to quickly produce the required tooling, which allowed Gripple to meet the market’s timeframe requirements.

Testing

While the tooling was being produced, quality and testing teams worked together to ensure all the testing needed to meet Network Rail’s standards was in place. The product surpassed both the mechanical and electrical tests needed to meet the requirements laid out in BS EN 50119.

As well as the tests needed to meet Network Rail’s standards, additional testing was also undertaken to ensure Gripple were completely satisfied with the product. Salt spray and UV tests were undertaken to prove the product’s performance was sustained after exposure to the elements. High and low temperature tests (including an ice expansion test) were also undertaken to prove that the product can continue to perform in harsh environments. Cyclic tests were undertaken beyond the Network Rail standard to prove the product’s longevity.

Summary

Electrification has the potential to be a big contributor towards the UK meeting its environmental targets, and Gripple says the new SwiftLine Rail Dropper has the potential to revolutionise OLE installation and allow Network Rail and its contractors to significantly speed up the electrification rollout. Gripple is confident that its ‘game changing’ SwiftLine Rail Dropper is faster, safer, and easier to install than anything else on the market. Minimal product training is needed to use the easy-to-use, tool-free dropper. This makes projects simpler and safer thanks to less time spent working at height or in the dark. All this allows better control of electrification projects, getting more done in every possession window, and even bringing forward project completion dates.


Head Office

Gripple Ltd, The Old West Gun Works, Savile Street East, Sheffield, S4 7UQ, UK

CONTACT CUSTOMER SERVICE

+44 (0) 114 275 2255

Email: [email protected]

Website: https://www.gripple.com/products/rail/swiftline-rail-dropper/

Distribution Partner: https://www.unipartrail.com/electrification-and-overhead-line-equipment/

Photo / video credits: Gripple

Sparking the Midlands

The Midland Main Line is a significant railway route in England, running from London to Sheffield in Yorkshire via the East Midlands. It comprises the lines from London’s St Pancras International station via Leicester, Derby/Nottingham, and Chesterfield. Express passenger services on the line are operated by East Midlands Railway. The line hosts a London suburban commuting service pattern to Bedford with a not insignificant freight flow on the route, focusing on a major aggregate operation at Mountsorrel.

Rail Engineer covered an Institution of Mechanical Engineers’ conference in June 2013. That event looked at the emerging national plan for railway electrification and, in particular, the proposals for electrification of the Midland Main Line onward to Sheffield. The well-developed outline proposals were presented by the then Network Rail route delivery director; supported by a robust technical strategy.

Unfortunately, the onward development was ‘paused’ by the Department of Transport resulting in a serious loss of momentum as contractors demobilised. More promisingly, on 18 November 2021, the Integrated Rail Plan (IRP) was published stating that electrification of the whole line would take place. Rail Engineer previously revisited the subject in April 2021 with an optimistic view of the delivery of new rolling stock and an anticipation of electrification through the entire route to Sheffield and Nottingham.

Stops and starts

The position in 2021 had stopped at electrification of the main line onward from Bedford to Kettering and the branch to Corby. However, currently, despite the ‘pauses’, we find the electrification work, led by SPL Powerlines, has progressed towards Market Harborough with much equipment installed and the route infrastructure adapted to suit. The choice of this route section addition lies in the fact that the bulk supply point was commissioned at Braybrooke as part of the full route-long electrification scheme.

It is noted that Braybrooke feeder station is needed to support the now commissioned London to Corby (L2C) scheme in 2021. The current feeder station at Long Meadow Farm, which replaced Sundon Feeder Station, feeds the existing Mk3b OLE equipment all the way to Corby via Kettering. The current traction system for L2C is not sufficient for more than two electric trains per hour. The Kettering and South Wigston (K2W) scheme ensures that the power, notably the voltage loss at Corby, is rebalanced with Braybrooke feeder station being brought online, and allows the new Class 810 from East Midlands Railway to maximise the use of clean overhead line equipment to power their trains.

The construction process now advancing with works to continue the electrification equipment installation northwards as far as South Wigston, near Leicester. In addition to the new construction, attention has been focused on the performance of existing Mk3b overhead contact system equipment South of Bedford. This was installed for the Bedford / St. Pancras scheme in the 1980s and was not designed for the high-speed running required for the developing, main route, Inter City style of service, frequency, and speed.

SPL is to support the proposed six electric trains per hour and line speed increases to 125mph (or greater than the maximum 90mph an electric multiple unit currently runs on the old Mk3b equipment). That scope forms enhanced renewal, and SPL is proposing to develop a new overhead line system to support more trains and enhanced line speed. To offer greater resilience, this will be done by increasing contact wire tension and changing to 120mm contact wire from the worn 107mm conductor and changing the catenary from the existing Mk3b AWAC to the new preferred Bz11.

Overhead line equipment ready to be installed between Market Harborough and Wigston.

Work under way

While the route electrification appears to proceed piecemeal there is much active and positive work under way, and Rail Engineer was pleased to be invited to SPL Powerlines’ administrative and technical base at Leicester, in order to hear about current progress and the positive developments within the current works.

The Midland Main Line activities are delivered through the Leicester base, one of the major construction depots at Cookes Cattle Arch. The current K2W scheme is a route of 37 route kilometres comprising of 76 STK, with three new substations and two new neutral sections being installed. Attention has been paid within the design to operational flexibility with the use of powered trackside switches where their cost can be justified.

SPL Powerlines UK Limited is a leading independent overhead line equipment provider with both a Principal Contractor’s Licence and a Plant Operators Licence. The business provides turnkey overhead lines capabilities from design, through installation and commissioning, to final testing. The company operates both within the main line heavy rail and the mass transit sector. The company is headquartered at Coatbridge in Scotland.

As principal contractor, SPL is appointed as the lead design organisation for the current route electrification works and is also providing the construction input. This includes route clearance works north of Kettering. SPL effectively forms the ‘Hub’ for the project. SPL is also undertaking all project assurance including integration, CSM, and dispositioned traditional client-based roles like project engineers (under the Agile Client Eastern proposals).

Site visit and meeting

Rail Engineer was pleased to be invited to the SPL Midland Main Line project offices at Cannock Street near Leicester and was able to listen to a presentation on the works currently under way between Market Harborough and Kettering, including the bulk supply point at Braybrooke. The presentation clarified the scope of the project and revealed that works were now authorised as far north as South Wigston near Leicester. South of Bedford, the scope of the works includes route upgrades for speed improvement and flexibility of working, in addition to electrification. This is the preferred method of approaching electrification, that is, to rationalise the route first.

The Minimum Viable Project philosophy has been applied to signalling immunisation, where the signalling scope is to support the electrification. While there is always concern that the costs of electrification projects may increase if they are required to upgrade other life-expired infrastructure on the route, this project has focused on true cost in the electrification ground and so is only undertaking immunisation signalling works.

The multi-million-pound programme supports the Government’s ambitions for decarbonisation and aims to deliver a greener, more reliable railway to connect passengers right the way between London and Sheffield, via Nottingham and Derby.

The phase of major work will see electrification around a 20km section between Market Harborough and South Wigston brought up to speed to eventually connect the entire route, following recent upgrades further south.

Much of the work is undertaken overnight while there are no trains running to keep railway workers safe and to keep disruption to a minimum. However, advantage is also taken of the ability to install equipment at weekends where diversions may take place via the alternative route through Melton Mowbray.

The visit was moved on to visit the construction site at Cooks Cattle Arch, alongside the main line. The base was formed to function as a base for the route electrification work with pre-assembly sites, welfare facilities, and material stores on site. The site was also the base for a significant fleet of very impressive plant that was conveniently based near the route works.

The site was very comprehensively equipped and of particular interest was the pre installation assembly work. SPL explained that it planned to minimise the work to be undertaken directly on the railway infrastructure with pre-preparation on the construction depot site. A major function undertaken there was the attachment of the small part steel work to electrification structures, supported by other works even including the structure identification plates. This off-track work was heavily maximised for safety and productivity reasons. Such techniques, and the agile use of plant is part of SPL’s High Output production philosophy.

The site is particularly well laid out to allow safe working and movement of vehicles and plant. Also extremely noteworthy is the energy management on the site. With the aid of portable solar panel units, the operations can be claimed to be completely carbon neutral, lighting and power supplies being supported by natural energy. In case of loss of this source, a generator is available to ensure continuity of work, but the use of that plant is rarely required.

A further arrangement of note is the methodology of handling electrification equipment prior to site erection. Where possible, the use of craneage is avoided by creating ‘stillages’ of units which can be handled on site by forklift truck and can be placed aboard construction rail mounted plant in the same manner. As much as possible was stored on pre-arranged stillages minimising handling both in the depot and on site.

Of note was the rationalisation of electrification structure piles and pile caps to minimise stocks. Piling is now the preferred method of electrification structure installation; the piles being driven by dedicated piling plant. This avoids the downsides of the earlier methodologies of grabbed excavation and concrete with its less than positive impact on the environment. The project has a ‘2 type’ of foundation approach, 610mm circular hollow section steel piles (CHS610) and a 1-metre concrete Augers. Through the project’s continuous development, with over 3,500 foundations installed, SPL has ensured that 90% of the foundations are 610CHS piles. The K2W foundations have now been completed months before energisation. This is unprecedented on large scale electrification projects and a real success of design & construction collaboration.

For the construction base, much emphasis had been focused on social issues, and awareness of neighbours and stakeholders had led to minimising the generation of noise and other nuisance. Good communication had also helped to build a productive relationship during the project, supporting an excellent model for the industry.

Considerable investment in road / rail access plant is a signature for modern electrification construction; particularly impressive was the long-reach access platform and the large Zeck plant accompanying the traditional SRS machine; an investment of over a million pounds.

Traction electrical power grid intake

The site visits were completed by a transfer to the grid traction power supply intake site and the connection from the high voltage national distribution power lines was clear to be seen. Considerable work had been undertaken here by National Grid, and the accompanying intake substation at the lineside was a significant piece of infrastructure investment.

The original traction power distribution design had been put together to feed the route-wide electrification proposals and had been planned as an exceedingly early item. It should be noted that electrification traction power supplies were a strategic issue and once planned could not easily be altered: a national strategy for the future is a real requirement. This is one that the project has been modelling for a number of years, based on both the 2040 and the 2050 Traction Decarbonisation Network Strategy (TDNS) requirements, with and without HS2!

Scope issues

There is considerable debate over the cost of electrification and during the discussions SPL showed that it was very much alive to the issue. To that end, much effort was being placed into identifying scope which was not part of the electrification works. For instance, it is felt correcting existing non-compliances should not be charged to the core electrification project but separately identified. This awareness is to be congratulated.

Within electrification scope, but not to be discounted, were items such as electrical bonding, with some 2,000 bonds being required: a low visibility but not insignificant workload and to be undertaken directly on the running rail infrastructure. This includes lineside fencing to ensure that GRP fencing panels are being installed at strategic positions along the route. The electrification system is not just a mechanical one:

The works generate a significant amount of testing; again, contributing to electrification cost. National Technical Specification Notices are a major factor also. Associated with these requirements, the project team emphasised the volume of ‘paperwork’ to be generated to enable entry into service but described some very robust systems to enable effective control and minimise bureaucracy. The maximum opportunity had been taken to utilise digitisation and minimise the hard copy paperwork.

Finally, the team were pleased to say they had a productive relationship with the route maintenance organisation and had enabled successful direct access to the project group.

External communication

In conjunction with SPL’s work on stakeholder and neighbour relations, for its part Network Rail is piloting a new way to keep people who live next to the railway in parts of Northamptonshire and Leicestershire better informed about upcoming work that might affect them.

The programme team are sending paperwork notification calendars to lineside neighbours and stakeholders. These give details of upcoming work in the Kettering and Wigston areas. The calendars will be accompanied by a letter, which gives details on how to sign up to receive future calendars digitally, and how to access a new interactive map.

Gavin Crook, principal programme sponsor has pointed out: “Our new digital notification system will help us provide residents with accessible, clearer, accurate information in a timely way.

“Although people can still choose to receive their notifications by post, we’re hopeful that most will sign up to the digital mailing list.”

Other partners

SPL emphasised that, while it was leading the project, other partners should be acknowledged. For instance, AtkinsRéalis had been developing the Approval in Principle ES 4 dealing with design, and Van Elle was a key sub-contractor partnership to support the electrification structure piling. For the section between Market Harborough and South Wigston, the route clearance works would be undertaken by Story & AMCO.

Not withstanding the significant infrastructure works under way, there is also a new fleet of trains on the horizon: the Class 810 from Hitachi. The rolling stock design and commissioning will be closely allied to the infrastructure works and Rail Engineer will be observing and reporting on the stock as testing, commissioning, and delivery progresses.

The project gives a real feeling of progress in the application of the vitally needed electrification of our railway system; a positive demonstration that the industry can deliver and succeed! One can anticipate we will eventually see the new trains running under wires for the whole of this vital route!! Many thanks are due to SPL Powerlines and its people, especially Annette White and Simon Skinner. Rail Engineer hopes to follow the project through with a final completed view of wires all the way to Sheffield and Nottingham. Thanks also go to Network Rail for permission to work with its contractor on the preparation of this article.


PDF Version of the article here: https://issuu.com/railmedia/docs/re_novdec_2023/18


Royston electrification: first zero emission work completed

During early October the Eastern region of Network Rail completed its first zero emissions engineering work.

The engineering work was associated with renewal and upgrade of the overhead line equipment through, and either side of, Royston station, involving the replacement of components supporting the catenary and contact wires. Many of the parts being replaced dated from 1978 and were therefore 45 years old. This work was scheduled to be completed over four successive night time possessions of both the up and down lines through the area. The work was successfully completed with zero carbon emissions by the use of novel welfare facilities and of hybrid, on-track machines which relied on battery power throughout the work.

Hamish Critchell-Ward, environment manager for the Eastern Region of Network Rail, outlined the objectives of piloting zero emissions working which forms part of plans to get to net zero by 2050.

This particular site had been chosen as it fulfilled a number of the requirements for a first trial of zero emissions and low carbon working. These included the scale of the work and the relative accessibility of the site.

The whole site was supported by an 80kWh battery that provided power for the welfare facilities and recharged the on-track machines ready for each of the four overnight possessions. The 80kWh battery had itself been charged off-site, using a large solar array, prior to being transported to Royston for the establishment of the worksite.

On-site lighting around the welfare facilities was provided by battery supported, solar charged, LED tower lights whilst lighting for the work was again provided by battery powered LEDs. In addition, the other tools used were battery operated and all consumable materials were recyclable.

Carbon costs

Hamish identified that currently such working has a slightly higher initial cost, fundamentally due to the battery and its support arrangements, but there are a number of hidden costs associated with diesel generators that ameliorate this. They include not requiring diesel fuel to be brought to site, with associated risks of spillage and containment, and the costs of topping up if required. In addition, the battery is claimed to function over 4,500 recharge cycles which, even at a daily recharge rate, would equate to around 12 years working life. A diesel generator is likely to require several maintenance visits over that period adding significantly to its whole life cost.

In practice the battery on site had commenced operation at around 90% charge and, after providing power to the worksite welfare facilities and charging the hybrid on-track machines for the duration of the work, still had 28% capacity remaining at the end.

A quieter solution

Other benefits of using battery power included the use of some of the first hybrid, on-track machines. As hybrids, these have both a diesel engine and a battery suitable for relatively short distance movement. On this site they were able to be restricted to battery-only operation with very marked reductions in noise. Indeed, the loudest element of the work was the warning sound that beeped whenever the unit was moving.

The fact that the welfare site was also battery powered meant no need for a grid connection or the alternative of a diesel generator, with a further reduction in noise. This has the added benefit of reducing disturbance to railway neighbours, especially during night works, and thus reduces the risk of work being curtailed due to complaints.

Suppliers

Vanguard Services Limited (VSL) provided the welfare facilities in the north car park at Royston station. These were supplied with energy from the 80kWh battery with associated external LED lighting, equipped with their own battery supply recharged using solar panels and small wind turbines. The hybrid on-track machines used for the actual overhead line work were recharged during the day, again from the 80kWh battery in the compound area.

Genista Energy, based in Dundee, supplied two products from its range to VSL to support the work at Royston. Gadget Gen80, one of its mobile battery storage systems, stored the necessary energy to power the welfare facilities, provided the welfare area lighting, and delivered the power to the Electric Vehicle Charging System which recharged the hybrid on-track machines, also supplied by Genista.

Both products are suitable for delivery to site, even relatively remote sites as may be found trackside.  The entire operation was therefore able to work off-grid and demonstrated that being off-grid need not be a challenge even when vehicles need to be recharged. Neither of the Genista products have any moving parts and, being relatively new, they are fully equipped with remote monitoring systems that facilitate management and supervision from afar.

The on-track plant was provided by Pro Rail Services based in Welwyn Garden City. They provided four hybrid MWEP/RR14 EVO-2-400 machines that successfully completed all work, from on-tracking through movement to site, working, and return to off tracking, in battery mode. Thus, no diesel fuel was used as part of the work. Pro Rail services prides itself on innovation and sustainability, especially leading to a low carbon worksite, and this was a useful project to demonstrate these capabilities with modern on track plant.

The machines themselves have an articulated and telescopic boom lift with a cage capable of holding up to three people and maximum operating weight of 400kg. The hybrid version has a 400Ah lithium battery driving two 5KW AC electric motors. The battery can support movement over a maximum of 12km, or over shorter distances combined with lifting and working as required. There is an onboard battery management system to control the battery operation and provide an onboard display of the current battery condition. As hybrid units they are also equipped with a diesel engine designed to use HVO fuel and a hydraulic pump able to operate the machine functions and, if necessary, complete off tracking.

A success story Overall, the work at Royston demonstrated that working towards a low emission environment with battery electric systems can deliver significant benefits and is already achievable for the right project scope. Indeed, it is estimated the use of battery energy storage at Royston saved around 750 litres of diesel fuel which delivered a saving of around 2.5 tonnes of carbon dioxide emissions. With ongoing developments in the technology, especially battery capacity, much more can and will be achieved in the near future.

Collision at Salisbury Tunnel Junction October 2021

What happened

At approximately 18:43 hrs on 31 October 2021, on a day that had been exceptionally windy and immediately after a localised period of drizzle, South Western Railway (SWR) passenger train 1L53, the 17:20 hrs from London Waterloo to Honiton, passed a red signal and collided with the side of Great Western Railway (GWR) passenger train 1F30, the 17:08 hrs service from Portsmouth Harbour to Bristol Temple Meads.

At the point of collision, the SWR train was travelling at approximately 52mph and the GWR train at 20mph. The collision took place at Salisbury Tunnel Junction, which is on the immediate approach to Fisherton Tunnel, near Salisbury in Wiltshire. Scan the QR code for an animation showing the paths of the trains involved.

The collision caused the front two coaches of the SWR train and the rear two carriages of the GWR train to derail. Both continued into Fisherton Tunnel for some distance before coming to a stop. Thirteen passengers and the SWR train’s driver required in-hospital treatment as a result of the accident. There was also significant damage to the trains and railway infrastructure involved. A potentially far more serious collision between the SWR train and an earlier train which was travelling in the opposite direction and crossed over the path of the SWR train was avoided by less than a minute.

Low Adhesion

Rail Engineer has reported extensively about work to manage the effects of leaf fall on the railway. When leaves fall on the track, the movement of trains tends to roll them between the wheels and rails forming a black film that is very slippery when wet and insulates when dry. This means that wet contaminated rails exhibit poor adhesion (values can be as low as 0.02µ), leading to difficulty in applying power and much longer stopping distances.

Dry, contaminated rails are less slippery but can lead to wrong side track circuit failures (occupied blocks can appear to be unoccupied). Clearing the trees can eliminate the problem almost completely. Rail head treatment trains (RHTT) can be used to blast the leaf film with water jets at a pressure of 1000-1500 bar, sometimes with the use of an adhesion traction enhancing sand/gel treatment applied from the RHTT or trackside.

Mitigations include speed restrictions, signage to identify high risk areas, and instructing drivers to use defensive driving (brake earlier and more lightly). Train features such as better wheelslide protection and various forms of sanding can improve stopping distances.

Each site has its own individual features and the weather introduces additional variables, especially wind and rain. This makes day-to-day operational risk management a multi-dimensional task that requires specialist technical skills and the ability to coordinate with the many organisations/departments involved.

In February this year, Andrew Hall, chief inspector of the Rail Accident Investigation Branch (RAIB), gave a keynote address at Rail Media’s Rail Safety Summit with the title: ‘Rarely is Not Quite Never’. He could almost have been thinking of the collision at Salisbury Tunnel Junction, where, according to the RAIB’s interim statements, a significant factor was low adhesion caused by damp leaf film on the rails.

Heavily contaminated railhead.

The railway community puts in a huge amount of effort each year to manage adhesion problems during the autumn leaf fall season, and although there are wrong side failures (SPADS, station overruns, etc), it is rare for there to be a collision.

Although the Salisbury collision was serious, it could have been a whole lot worse, as a third train cleared the junction just one minute before the two-train collision. This was described in the 113-page report published by RAIB in late October 2023, just before the second anniversary of the collision.

The final RAIB report discusses the many controls and mitigations the industry uses to manage the risk of a collision in low wheel/rail adhesion conditions and how almost all failed on 31 October 2021. RAIB concluded that the causes of the collision were:

A) Wheel/rail adhesion was very low in the area where the driver of the SWR train applied its brakes, because:

  • There was leaf contamination on the railhead, resulting from the weather conditions on the day of the accident and since the last rail head treatment run.
  • The impact of the leaf contamination had been made worse by a band of drizzle that occurred immediately before the SWR train passed.
  • There was an increased density of vegetation in the area and,
  • Network Rail’s Wessex route had not effectively mitigated the railhead contamination.

B) The driver did not apply the train’s brakes early enough when approaching the signal protecting the junction to avoid running on to it, given the low level of adhesion.

C) The braking systems on the SWR train were not capable of mitigating this very low adhesion.

This article summarises the key points and conclusions in RAIB’s roughly 36,000 word report. Anyone wanting more detail should read the full report.

The report discusses the actions of members of staff in Network Rail management in operations and maintenance, SWR management, and the driver of the SWR train. As is normal process, RAIB discusses each area in turn.

Vegetation

Before arriving at the conclusions in point A), RAIB discussed the actions of Network Rail (NR). It noted how vegetation on the route taken by the SWR train had significantly increased since the last days of steam and the early days of diesel operation (1967-73). It examined processes for identifying and assessing the risk posed by lineside trees and foliage, and processes for planning and carrying out clearance, before assessing whether and how well they had been complied with.

The investigation identified several issues with process between 2018 and 2021. It also found that that no action had been taken to manage the vegetation over the approaches to the accident site, yet the risk scores had not changed despite the vegetation continuing to grow. RAIB said this called into question the robustness of the process. Other issues such as the output of inspections not being entered into NR’s Ellipse asset management system were also identified.

It described how the organisational relationships between the various departments within Network Rail were supposed to work and the standards applicable to managing, preparing, and collaborating internally and with the train operator in planning and responding to autumn and low adhesion incidents. use QR code to see organisation charts.

RAIB identified issues with how this worked in practice and also with standards, processes, skills/competence, and people shortages.

For the managing lineside foliage process, RAIB said that the standards were complex and seemed aimed at both postponing work and being insufficiently precise which allowed inspection results to stay the same while the foliage becomes more overgrown.

It also identified some lack of competence and experience, difficulty in organising contractors to carry out work, and difficulty in getting access, compounded by the ban on red zone working.

The report recognised that it is not practical to eliminate leaf film on rails and described many of the techniques the industry has developed to clean the railhead, either with railhead treatment trains (RHTT) or lineside adhesion gel applicators. RHTTs were scheduled to run on this section twice a day during the week and once a day at weekends. Fewer runs at weekends were reported to be the result of weekend engineering work disrupting RHTT diagrams, but it was clear that the risk is just as acute at weekends as on weekdays. On the day of the collision, the RHTT had not run. RAIB explained that staff in the Wessex Integrated Control Centre (WICC) could call for additional runs in response to reports of low adhesion but hadn’t realised the area was at risk that day despite the windy weather.

WICC could also call on Mobile Operations Managers (MOM) to carry out inspections of the railhead in high-risk areas, and RAIB reported that such an inspection had been called for, but no MOMs were available. It added, however, that MOMs had reported that they were unable to work trackside without a line blockage and had been asked to assess rail head condition from overbridges and lineside fencing, an exercise MOMs thought was of very limited value.

South Western Railway

RAIB commented that the requirement to inform drivers about low adhesion and for drivers to feedback about low adhesion was not being consistently followed, illustrating this with a photograph of a low adhesion notice in comparatively small type on a noticeboard behind glass and with comments from other drivers that they did not have enough time to study all the notices.

The train in question was a three-car class 159, although it should have been a six-car/two-unit train. Longer trains generally deliver better braking performance on poor adhesion than short ones.

The driver

RAIB’s conclusion that the driver braked too late was based on analysis of the SWR train’s On-Train Data Recorder (ODTR) and interviews with the incident train’s driver and other drivers who operate class 159 units on this line.

The analysis, from this and other trains, showed that the driver, having seen the double yellow at signal SY29R, braked much later than he usually did and later than other train drivers on that route. During the high winds earlier that day, a tree had fallen on the line to the southwest of Broken Cross bridge which the driver observed on the way up to Waterloo (during daylight).

The driver explained that when he saw the double yellow signal, he thought there would be low adhesion at the site of the fallen tree, so he decided to look for the tree and brake immediately after it. But it was dark, and he missed the tree and only initiated braking in step 1 over a mile after SY29R. He rapidly increased the brake rate to step 3, the maximum rate, before selecting emergency brake shortly after. The train’s wheel slide protection and sanding were unable to provide the deceleration rate required in the low adhesion conditions caused by the leaf film and the drizzle that passed over the area shortly before the SWR train approached. In simple terms, when all the other risk controls had failed, the driver – the last line of defence – made a mistake, leading to the collision.

Signal spacing

But it wasn’t quite as simple as that. RAIB found that the 3.1 km between signals SY29R and SY31on the approach to Salisbury Tunnel Junction provided an excessive braking distance for passenger trains, meaning that drivers must delay full braking until after they have passed the double yellow aspect signal (SY29R), otherwise they could stop short of the red signal (ST31) and/or incur time delays on their journey.

The driver involved in the collision said he would normally have started braking at Broken Cross bridge. However, on 21 October 2021, the driver decided to brake at the fallen tree, 250 metres beyond the bridge, but, having failed to see the tree, only started braking approximately 1,000 metres beyond the bridge. The current applicable standards are RIS-0703-CCS and NR/L2/SIG/30009/D220 which states:

“If the distance is significantly greater than the minimum then this may lead to drivers continuing at the permissible speed and trying to judge when to brake with the risk of SPAD, or braking early and coasting leading to an increase in journey time or loss of capacity.”

Although these standards recognise the risk, the signalling approaching Salisbury Tunnel Junction pre-dates those standards, and there was no requirement for retrospective action.

Actions since the collision

In the two years between the collision and the publication of the RAIB report, lessons have been learned and actions agreed. RAIB reported that a joint internal industry investigation was carried out which recommended actions for Network Rail and SWR. These actions broadly align with RAIB’s own, described below.  Other industry bodies including GWR, RSSB, the Seasonal Challenge Steering Group, and the Rail Delivery Group also carried out a number of actions. An item not seen elsewhere in the report is the plan to fit Single Variable Rate Sanders to the SWR class 159 fleet. This modification can reduce the braking distance of trains in low adhesion conditions.

In December 2021, ORR issued an Improvement Notice to Network Rail requiring it to carry out a number of improvements that broadly correspond to RAIB’s recommendations. ORR had reported that Network Rail had complied with the notice and “taken action to manage the risk from adverse railhead conditions caused by leaf fall”. The actions taken include:

  • Engaging with stakeholders and reviewing data to update risk assessments and identify new and existing sites at high risk of low adhesion.
  • Targeted vegetation removal work at the highest risk sites.
  • Implementing changes to the railhead treatment programme including revised treatment circuits and speed, and trialling new treatment products.
  • Strengthening mitigation processes when railhead treatment is missed.
  • Briefing autumn working arrangements to relevant people. The arrangements include inspecting high-risk sites and auditing railhead treatment effectiveness.
  • Strengthening assurance arrangements for autumn management.
  • Planning future engineering works around the railhead treatment circuits and trialling new technology to identify railhead contamination.

RAIB recommendations

RAIB made 10 recommendations, the text of which is too long to publish here. Instead, we have quoted the intent of each recommendation and the organisation(s) to which each was addressed.

Recommendation 10 needs explanation. This article has not discussed the structural performance of the trains during the collision, nor the evacuation, but recommendation 10 relates to the difficulty some passengers had in opening bi-parting interior power doors on one of the class 159 coaches.

1: Network Rail: To have autumn working arrangements that more effectively manage low adhesion risk, as a result of leaf fall.

2. Network Rail: To have seasons delivery specialists that are more effective in managing Network Rail’s seasonal risk.

3. Network Rail: That off track staff are sufficiently competent and confident to undertake the tasks assigned to them by Network Rail standards.

4. Network Rail: To be able to make more effective decisions regarding the management of emerging and potential low wheel/rail adhesion conditions.

5. Network Rail: To improve wheel/rail adhesion conditions through the application of improved understanding of the effectiveness of railhead treatment regimes.

6. Network Rail: To enable the effective assessment by Network Rail of the risk of overrun at signals which have HRLA sites on their approach. Network Rail

7. Network Rail: To reduce the risk of overrunning signals at danger where there is a line speed change on the approach after the preliminary caution signal.   

8. South Western Railway: Drivers to be able to identify areas of low adhesion and report them, if appropriate.

9. Rail Delivery Group: The industry to realise the potential benefits of future technologies to enable trains to better cope with low wheel/rail adhesion when braking.          

10. Porterbrook, Angel Trains, and Eversholt Rail: To minimise the risk that passengers are unable to evacuate from class 158 and 159 carriages.      

Conclusion

RAIB’s in-depth report identified the many risk controls that contribute to the safety of the railway in autumn, low adhesion conditions, and, in most cases, found fault with the application of these controls. It is to be hoped that this accident has been a wake-up call for increased vigilance, competence, and attention to detail. One omission appears to be any recommendation aimed at significantly reducing the quantity of trees and other foliage around the railway to largely eliminate the risk of low adhesion at source. Comparing images from 50 years ago with today it seems that, in many areas, open countryside has been replaced by tunnels of trees. Perhaps it concluded that the task of so doing is too great?

Nothing went wrong – except poor adhesion

On 19 October 2022, five 100-tonne cement tank wagons were derailed at Petteril Bridge Junction in Carlisle. Two of these fell off the bridge with one landing upside down in the river. No one was injured and very little cement was spilled, though the track and bridge suffered significant damage. Due to this, and the difficulties of erecting a suitable crane close enough to the derailed wagons, the lines from Carlisle to Newcastle and Settle were blocked for seven weeks.

Immediately after the derailment, the Rail Accident Investigation Branch (RAIB) advised that it was ‘almost certainly’ caused by a wheelset having large flats and, consequently, false flanges passing through switches at the junction. 

This was also the cause of the derailment at Llangennech in August 2020 as Rail Engineer reported in issue 194 (Jan-Feb 2022). In this case, the wheel flats were the result of defective brakes and the RAIB report identified significant failings in wagon maintenance. Other previous freight wagon derailments had also been caused by poor wagon maintenance. Hence RAIB’s chief inspector at the time, Simon French, stressed that the safe maintenance of freight wagons has to improve. Against the background, some assumed that the Petteril Bridge derailment had also been caused by poor wagon maintenance.

Yet RAIB’s Petteril Bridge report into this accident shows that it was not caused by poor maintenance. Indeed, no-one was in any way at fault, nor was there any equipment failure. It revealed that it was caused by the train experiencing poor adhesion over an hour before it derailed.

6C00 and its journey

Freight train 6C00 consisted of a Class 66 locomotive hauling 14 JPA tank wagons each weighing about 101 tonnes, including the 80 tonnes of cement each wagon carried. These wagons had been maintained within the required periodicity and had no significant defects. 6C00 was the 17:15 from Clitheroe Castle Cement sidings to a freight yard north of Carlisle station. It had a single-pipe air brake system in which the pipe both supplies air to the wagon’s brake reservoirs and controls the braking.

The wagon brakes are applied when the brake distributor senses a reduction in air pipe pressure and then admits air from a reservoir into the brake cylinders at a pressure proportional to that of the reduction in air pipe pressure. This then forces brake blocks against the wheel treads through a system of rods and beams.  The wagons have no wheel slide protection (WSP) system. Though such systems are common on passenger trains, almost all freight wagons lack the electrical supply needed to operate a WSP system.

Rail accident interim report describing x

6C00 was prepared at the Clitheroe cement terminal and joined the primarily freight-only line between Blackburn and Hellifield at 17:25. Webcam footage showed that all train wheels were rotating at this point. Eight minutes later the driver carried out a running brake test as required by the Rule Book. This applied the brake for 17 seconds and reduced the train’s speed by 11mph.

The train reached Hellifield at 18:00 after which it joined the Settle to Carlisle line which goes over the north Pennine Hills and is England’s highest railway. From Settle, 6C00 had a steep ascent for 24km at an average gradient of 1 in 107, a flatter 10km stretch along the top of the hills, followed by a 24km descent at 1 in 120 to Petteril Bridge Junction.

6C00 was travelling at close to its maximum speed of 60mph before starting its climb. Despite the driver applying maximum power, the train speed up the long gradient was around 25mph and, at one point, dropped to 17mph. The On Train Data Recorder (OTDR) showed that the locomotive was operating at its adhesion limit and so experienced frequent wheel slip. The locomotive managed this by reducing power and depositing sand on the railhead. The line also has traction gel applicators to assist trains up its steep gradients.

The train reached the line’s 356-metre summit at Ais Gill at 18:55, after which the driver made the first of many short brake applications on the long descent to Petteril Bridge Junction. By 19:53, 6C00 had slowed to 20mph as it approached the junction. As it passed over its trailing points, the leading wheelset of the ninth wagon derailed and destroyed these points so that subsequent wheelsets were derailed.

The ninth and tenth wagons then demolished the bridge parapet wall and fell into the river below. This caused the coupling and brake pipe between the fifth and sixth wagons to separate, which automatically applied the train’s brakes. The driver then advised the signaller who blocked all lines to traffic.

It was found that the derailed wheelset had flats around 290mm long and 25mm deep which resulted in a large false flange on the outside edge of the wheel. The wheelset became derailed when its false flange split the closed switch rail from its stock rail and rolled it over. The damaged points then derailed all the following wheels. The Llangennoch derailment was caused by a wheel flat 230mm long and up to 15mm deep.

Why the flat?

From an analysis of brake applications from the OTDR and false flange marks on points along the route, RAIB concluded that the wheelset stopped rotating when the driver made a 30 second, 35% full service brake application approaching the 30mph permanent speed restriction (PSR) at Dent station which is close to the line’s summit and about 86km from Petteril Bridge Junction.

The RAIB report considers that a wheelset can stop rotating due to one or more of the following:

  • 1. A handbrake is left on before departure.
  • 2. Brakes apply due to a faulty air brake system. 
  • 3. Brakes apply due to object becoming caught within the brake rigging.
  • 4. An object jammed between brake rigging and wheels.
  • 5. The wheelset’s axle bearings seize.
  • 6. There has been a brake application in conditions of low wheel/rail adhesion.

Having systematically discounted items 1 to 5, the investigation focused on the sixth possibility.

At the time of the accident, adhesion on the Settle and Carlisle line was poor as shown by the way that the locomotive had slipping wheels as it climbed to the summit. Drivers on trains climbing to the summit from Carlise that day also reported low adhesion conditions at multiple locations. From OTDR data, gradient and train weight, RAIB was able to determine that adhesion (coefficient of friction between wheel and rail) on the climb to the summit was as low as 0.07 in one location even though sand had been applied to the rails. This compares with typical adhesion levels on a clean rail (wet or dry) of at least 0.15.

It was windy as 6C00 approached Dent, which is the highest station in England. A weather station there recorded average wind speeds of around 24 to 30 km/h, gusting to 40 km/h. With the line at this location being also particularly exposed, leaf fall in mid-October, was quite likely. This station also recorded an air temperature of 9°C, only about 1°C above the dew point. Hence it was likely that there was railhead condensation. Indeed, signallers further north noted that the rails were damp. 

Dent had no record of any abnormal adhesion problems and so was not considered to have a leaf fall adhesion risk. The line here generally runs through open moorland, though there is a small group of trees on a 50-metre section of the line where 6C00 would have braked for PSR at Dent. There conditions were commensurate with low adhesion.

The RAIB investigation found that the brake application approaching Dent would have produced a retarding force of 3.6 kN per wheel. For a wheelset to slide under that level of braking, the adhesion would have to be less than 0.03. 

From a study commissioned for a previous investigation, RAIB estimated that a 30-second wheelslide would produce a wheelflat about 60mm long and 1mm deep. If the wheel is to rotate once the brakes have been released, the rotational force on the wheelset has to generate enough force to overcome the 25-tonne weight on the axle for sufficient time to lift it by 1mm. The study showed that this would need a coefficient of friction greater than 0.07. Once the wheels started to slide, their flats got longer, and it became progressively more difficult for the wheel to rotate.

The report considered why only one wheelset on the train stopped rotating. It was considered possible that this wheelset was the first to experience insufficient adhesion for the brake force applied at that moment and that its slide increased adhesion for subsequent wheels.

OTDR speed and braking data.

Detecting the slide

With 6C00 running for an over an hour with a sliding wheelset, the investigation considered whether this should have been detected before the train derailed. With no engineered system in place to detect wheelsets that were not rotating, this would have required human intervention.

When the train passed Dent, it was dark. It then passed seven manual signal boxes before it derailed. The signallers there were required to observe the train’s tail lamp to confirm that it is complete and be alert to any obvious problem with the train. None of the signallers heard or saw anything amiss with the train. Although video footage at three locations showed sparks from the stopped wheelset, in some cases this was not clear until the video was enhanced.

As 6C00 reached Lazonby & Kirkoswald and left the last of the three axle counter sections controlled by Culgaith signal box, the signaller there noted that these three sections were still shown as occupied. He/she then contacted the next signaller at Low House to check if the train was complete. To do so the signaller stood on the signalbox balcony to observe the tail light but did not observe any sparking possibly because the area around the signalbox is well lit for its adjacent level crossing.

Axle counter sensors detect the passage of wheels by the distortion of a magnetic field. They are designed to detect with a compliant profile which allows flanges to be 6.5mm deeper than nominal. On the sliding wheel, the flange was about 20mm deeper than nominal. This would have been detected as non-compliant and given the signaller a fault indicator showing the track section as occupied.

The report considered whether signallers should arrange to have trains stopped and examined in the event of sequential axle counter section failures. It concludes that the Rule Book is not as clear in this respect as it refers to track circuit failures without clarifying that, as far as the Rule Book is concerned, axle counter sections are also track circuits.

The Rule Book also requires drivers to “look out from time to time to make sure that the train is following in a safe and correct way”. However, not surprisingly, the driver did not consider it safe to lean out of his cab window at 60 mph on a cold, windy night. Even if he/she had, the sliding wheelset was 150 metres from the driver who was therefore less likely to see the sparking than the signallers who saw the train passing.

It was noted that the ORR is encouraging train operators to reduce the risk of passenger fatalities from leaning out of train windows. It was therefore questioned whether this Rule Book requirement puts drivers at risk, especially when it is dark, and they cannot be sure it is safe to put their heads out of the window.

Satellite view of braking whilst approaching Dent.

Preventing repetition

Whilst wheel slide when braking is common, it is quite rare for wheels to continue to slide after brakes have been released to the extent that a deep flat is created. Indeed many, including your writer, found it difficult to believe that this is possible on a defect-free wagon. Yet this is not the first time that this phenomenon has caused an accident. For example:

  • Two rails were fractured between Pencoed and Llanharan in March 2021 after a wagon wheelset with a 185mm flat restarted rotating.
  • A Rail Head Treatment Train (RHTT) at Dunkeld & Birnham was derailed then rerailed itself at the next set of points in October 2018.
  • In January 2006, three broken rails were caused by wagon wheelset that acquired a 120 mm flat on long descent from Meldon Quarry and then restarted rotating.

The prevention of such accidents requires better adhesion management and /or detection of locked wheels by rail staff, trackside devices, or on-wagon sensors. These mitigations are considered below.

RAIB considers that the seasonal adhesion management regime may not fully recognise the risks to freight trains as this is driven by issues faced by passenger trains. Yet it found no evidence that the likely slide initiation location at Dent was at abnormally high risk of leaf fall. When considering the level of risk, the small clump of trees in open moorland at Dent would seem to present a trivial risk compared with, say, the large number of trees in the cutting approaching Salisbury tunnel.

Between Dent and Petteril Bridge Junction, 6C00 passed seven signalboxes at which the signallers were required to observe the train’s tail lamp and be alert to any obvious problem with the train. Whilst a signaller may notice a locked wheel, the report shows why it is not realistic to rely on signallers to detect non-rotating wheels, especially as much of the railway is controlled by power signal boxes. It also shows why it is even less realistic to rely on the driver to do so.

Trackside systems include wheel impact load detection (WILD) sites that identify vehicles with excessive dynamic loads. Although this includes those with flats on their wheels, such systems cannot detect non-rotating wheels. There are also hot axlebox detectors (HABDs) that measure radiated heat to detect failing axle bearings. In some cases, HABDs can detect the excessive temperature of non-rotating wheels though these are not generally configured to trigger alarms.

The investigation shows that sequential axle counter section failures have the potential to alert signallers of sliding wheelsets. However, this is not their design intent, and these would only detect large wheel flats on wagons already significantly at risk of derailment. 

If trackside systems were to be relied upon to detect all instances of sliding wagon wheels before they caused a derailment, these would have to be placed a short distance apart throughout the rail freight network at a significant cost. In this respect it is noteworthy that the investigation could only assess the state of the wheelsets concerned six days before the derailment as this was when the wagons in 6C00 last passed over a WILD site.

On-wagon sensors

Although modern passenger trains are fitted with numerous sensors, freight wagons generally have none as they have no electrical supply. Yet recent developments show how wagon-powered sensors can prevent derailments and offer significant other business benefits.

One such initiative is the iWagon which is the result of a 10- year collaboration between Knorr-Bremse and wagon leasing company, VTG Rail UK which also owns the cement wagons derailed at Petteril Bridge Junction. Their iWagon has axle-powered generators to provide an electricity supply for wheel slide protection and various sensors which include GPS location, wheel loading, axle-lock detection, handbrake status, brake condition monitoring and the identification of harmonic frequencies to identify deteriorating components.

VTG’s iWagon.

The iWagon can provide alerts and relevant information to the driver, Network Rail, and other stakeholders. As well as preventing derailments, these digital wagons could assist Network Rail in identifying low adhesion hot spots. Sensor data and wagon mileage can also be used to optimise maintenance to increase wagon availability. In this way, digital wagon conversions have the potential to pay for themselves.

VTG commenced a four-month trial of nine iWagons on 2 October, on Tarmac’s daily return service from its cement plant at Dunbar to its depot at Seaham in County Durham. Data from this trial will be evaluated in January ahead of the first 50 production wagons planned for 2024. This trial was intentionally planned to take place during the leaf-fall season.

Recommendations

The report’s key recommendation was, in summary, that Network Rail and the freight operating companies should work in collaboration with RSSB to review the risks faced by freight wagons during normal brake applications in foreseeably low adhesion conditions including sliding wheelsets. This review’s findings are then to be used to evaluate the processes, standards, and guidance for rail adhesion management, and produce a time-bound plan to implement the resultant changes.

The report also made two other recommendations to ensure/clarify the rules relating to sequential axle counter failures and to determine the effectiveness of the Rule Book requirement for drivers to regularly look back along their train and assess the risks of this activity.

Incidents of sliding freight wagons wheelsets caused by low adhesion are difficult to detect. Though these are fortunately quite rare, the Petteril Bridge Junction derailment shows these are potentially high-consequence events. Hence it will be interesting to see how the industry considers that this risk is best addressed from the risk assessment that RAIB has recommended.

In the long term, digital wagons will be able to trigger an alarm if a wagon had a locked or sliding wheelset. However, this is not yet a mature technology and fitting these to the UK’s 14,000 freight wagons is an expensive exercise. Yet digital technologies have been shown to have a fast rate of development and it would seem that digital wagons have real business benefits. Hence, it may not be that long before undetected non-rotating freight wagon wheels are a thing of the past. Rail Engineer will continue to report on the development of digital wagons.

Levenmouth almost reconnected

On 25 August, Scotland’s Transport Minister, Fiona Hyslop and Alex Hynes, managing director of Scotland’s Railway installed the final golden pandrol clip to mark the completion of track laying on the Levenmouth Rail Link project. This work entailed laying 19km of track over a number of phases since March 2022.

Rail Engineer explained how this track laying was done in issue 200 (Jan-Feb 2023) and the nature of this project and its preparatory work in issue 197 (Jul-Aug 2022). To recap, this project is reopening a mothballed line which was closed to passenger services in 1969. Leven last saw freight services in 2001. The Levenmouth area is the largest settlement in Scotland without a rail link and is generally a deprived area due to the closure of its coal mines and other industries.

With the completion of track work, Rail Engineer was on site in October to see what remained to be done to complete the job.

Regenerating Levenmouth

Since 2014, the Levenmouth Rail Campaign (LMRC) has proposed regenerating the Levenmouth area by re-opening this closed line. This resulted in a debate in the Scottish Parliament in September 2017 which showed strong cross-party support for its reopening. The case for the line was made in the LMRC’s booklet which the Transport Minister endorsed during this debate. He then announced that Transport Scotland would undertake a study on the best travel options for the area.

Booklet explaining both the benefits and issues associated with the line’s re-opening

After this study reported in favour of a re-opened railway, in August 2019 the Scottish Government announced the go-ahead for detailed design work to support its re-opening. Devegetation work started late in 2020 and was followed by site investigations early in 2021. In January 2022, the Scottish Government confirmed that £117 million was to be invested in the Levenmouth railway and that it will open in spring 2024. The first mile of track from Thornton North Junction was laid and the first construction compounds were establishment in March 2022.

Booklet explaining both the benefits and issues associated with the line’s reopening.

For almost all its length, the 9.7km long Levenmouth branch has few straight sections. Hence its line speed is generally 45mph. From its junction with the main line, it closely follows the River Ore in a steep valley and then populated area by the River Leven. Although it had single track when it closed to passenger services, to ensure timetable resilience, the reopened railway is double track except for a 1.5km single line section from Thornton North Junction.

The project’s aim is to make “Levenmouth a better place to live, work and play” and is being delivered on behalf of the Scottish Government with Network Rail in the lead with AmcoGiffen, AtkinsRéalis, BAM, Siemens, SPL, Story, QTS, and Rail Systems Alliance Scotland (RSAS) as suppliers.

This report is based on my site visit which focused on progress at the line’s two stations. Figures in brackets are metres from Thornton North Junction.

Leven station

Leven (9,654) is the end of the line and so was the site of the golden clip ceremony. When completed, its station will have a single seven-metre-wide, 205-metre-long island platform, accessed by a ramp between the buffer stops. A pavilion between the buffer stops and car park will contain a waiting area, ticket machines, and a welfare facility for Scotrail staff. Separate cycle storage will be located adjacent to the pavilion. An additional waiting shelter will be provided on the island platform.

Its car park will have 133 spaces, including 12 for electric cars. To create a quality public realm, the area around the station is the subject of a placemaking study which is considering a central boulevard and waterfront path from station to town.

The Principal Contractor for the station works is AmcoGiffen. At the time of my visit around 40 metres of the station platform had still to be constructed. This platform is crossed by the 75-year old River Leven Road (Bawbee) bridge which was in poor condition and required new abutments and redecking. This work is the responsibility of Fife Council who agreed that it should be managed by the project team as it is an integral part of the work to reopen the railway. Hence, work on part of the Leven platform was deferred until the bridge work was substantially complete.

This bridge work also required the provision of a temporary road with a temporary bridge over the River Leven which was brought into use in May. This also has an interface with the station as the raised road to it will have to be levelled for the construction of the station car park. This work cannot start until the Bawbee bridge re-opens.

The Bawbee bridge takes its name from the toll to cross the original chain-suspension footbridge built in 1821. This was a halfpenny or, in Scots, a Bawbee.

Cameron Bridge

The other station on this line is at Cameron Bridge (6,480). Its car park will have 125 spaces and there is room for a further 300 spaces should these be required after the railway opens. This is quite likely as the station is situated off the busy A915 road which runs through Fife’s East Neuk to St Andrews and so it could be a significant rail head for the area.

There are 8,000 people living within 2km of the station. This includes the settlement of Methilhill which is to be connected to the station by a 140-metre long footbridge over the River Leven, consisting of 2 x 21-metre and one 70-metre spans. As described later this is being provided by a separate active travel project.

The station consists of two 196-metre platforms with a footbridge and lifts. Like Leven it will have a Pavilion structure with a waiting area and ticket machines. There will also be storage for 16 cycles.

Work on the station started in January. At the time of my visit the platforms were almost complete, and the footbridge and lift-towers recently installed. The bridge was fabricated by M&S engineering of Dumfries and installed in 11 separate lifts over two days in September.

Signalling and electrification

The line is double-track except for a single line section from Thornton North Junction (0) to Double Dykes Junction (1,451). The only other point-work is the crossovers before Leven’s terminal platforms. For trains leaving Leven there is a Down to Up line crossover (8,800) with a Down to Up line crossover (9,230) for trains approaching Leven.

With most of the route being double-tracked, the signalling headways allow for at least a twice-hourly train service. Train detection at Leven station and on the branch’s single-line section at its fringe with the Fife Circle is D.C. track circuits. Elsewhere, 22 Frauscher axle counters have been installed. In total, the line requires 15 signals. These, and other trackside equipment, are controlled by factory-built location cases throughout the route. The line’s signalling system uses Siemens Mobility’s Trackguard Westrace Trackside System to interface with the trackside equipment, in conjunction with the company’s Trackguard Westlock Computer Based Interlocking.

The line requires two GSM-R masts to be installed. One will be at Cardowie (2840) and another at Pfaudler’s Yard (9200) which is also the location of the signalling Principal Supply Point. Both this and the GSM-R mast had yet to be installed during my visit though I was advised that troughing was 95% complete.

The Scottish Government’s plan to decarbonise its railway includes an interim plan for partial electrification of the Fife lines. This requires electrification of the Levenmouth branch. However, with orders yet to be placed for the required battery EMUs, it will be some time before Fife and its Leven branch see electric trains. To minimise the disruption and cost of the branch’s future electrification, foundations are being installed as an integral part of the construction work. As this is being done in accordance with the completed electrification detailed design for its electrification, there will be no infrastructure clashes or signal sighting issues when the line is electrified.

Bridge parapets are also being raised to the height required by electrification standards. During my visit, around 60% of the required 365 foundations had been installed.

The project completion programme requires rail corridor work to be completed by 4 December for progressive commissioning of the route with signalling commissioning planned to take place on 7 January. This will see the line controlled by Edinburgh Signalling Centre when it will become part of the main line network. It will also enable driver training to commence.

Then the only significant work remaining will be the two stations which are planned to be completed in Spring 2024.

Crossing the line

Whilst the line was mothballed, it was crossed by various paths. For understandable reasons, Network Rail was unable to create level crossings on the line. Hence, various paths across the line had to be closed where the significant cost of a footbridge could not be justified.

This was not such a problem at the populated eastern end of the line where the Leven Programme aims to make the area a hub for tourism, business, and industry. This is a partnership of various organisations including the Scottish Environmental Protection Agency (SEPA), Scottish Natural Heritage, Sustrans, Fife Council, and Scottish Enterprise.

This programme aims to maximise opportunities for active travel in Levenmouth along a 5km stretch of the river from Cameron Bridge to Leven. It is part-funded by the Scottish Government’s Places for Everyone programme. In addition, Fife Council received £19.4 million from the UK Government’s Levelling Up Fund for the Leven Connectivity Project and Glenrothes Riverside Park.

Though the Leven programme is outside the scope of the rail link project, Network Rail is working closely with it to minimise its cost and has submitted planning applications for three footbridges which will become part of this active travel network. With low land by the River Leven and disused coal mines in the area, these planning applications required flood and mining risk assessments.

These footbridges are:

  • Methilhill (6,400), a 138-metre footbridge over the River Leven between Methilhill and the Up platform at Cameron Bridge station. This has a 72-metre span over the river and 3 x 22-metre spans over the low ground.
  • Duniface (7,070), a 144-metre footbridge of 6 x 24-metre spans over the railway and the River Leven. This carries a Fife Core Path between Methilhill and Kennoway.
  • Mountfleurie (8,270), a 108-metre footbridge of 2×14-metre and 4×20-metres spans over the railway and Fife Heritage Railway. This carries a Fife Core Path between Kirkland and Mountfleurie.

The paths over the line at Duniface and Mountfleurie will remain open until planning consents have been received and work to construct new bridges gets underway.

The thinly-populated western part of the line has four crossing points. These are not core paths or have no legal rights of way and were permanently closed in August. One of these, at Double Dykes (1,196), attracted a petition calling for it to remain open which collected 1,400 signatures with the local MP raising this matter in the Westminster Parliament. This is an unfortunate example of how it can be difficult to build a railway without upsetting some of the local population.

At Woodbank (4,900) a three-hectare field bounded the Rivers Leven and Ore was accessed by a path across the railway. To maintain the farmer’s access, an underpass was constructed. This incorporated two-metre-square and three-metre-square precast box units for pedestrian and vehicular access. Earthworks were required to provide a 1:7 slope to this underpass.

The timetable challenge

To present a balanced view, the campaigner’s booklet explained the issues that had to be addressed to reinstate passenger services as well as making the case to re-open the line. This showed that, whilst the Levenmouth construction works were relatively straightforward, developing a timetable to provide the required connectivity would be a significant challenge.

With track and station capacity on the existing routes to and through Fife constrained, the booklet considered that accommodating trains on an additional route would demand considerable ingenuity as well as resources of trains and crews.

This point was highlighted in ScotRail’s recent consultation about its interim 2024 Fife timetable to provide Leven with a train service. This was needed as the required trains and traincrew for the desired service will not become available until 2025.

The current off-peak timetable gives Fife four stopping services per hour. Two of these go through Kirkcaldy to Perth or Dundee, and two go through Dunfermline to terminate at Cowdenbeath or Glenrothes. Following electrification elsewhere, this is now ScotRail’s most intense urban diesel service and requires about a third of its 74 DMUs operating services out of Edinburgh.

When the new line opens, the challenge for train planners is to give the Levenmouth branch an acceptable service with the available trainset and crew resources whilst not detracting from the existing timetable. A further requirement is to give Leven a journey time of around an hour from Edinburgh. A journey time of around 65 minute is possible via Kirkcaldy, though the route via Dunfermline takes about 80 minutes.

As shown in the table, the published 2025 off-peak timetable offers Leven two trains an hour, one via Kirkcaldy and one via Dunfermline. This requires a 30% increase in train utilisation time which requires six additional DMUs which will not be available when the line opens.

Hence, an interim timetable is needed in 2024. For consultation, ScotRail produced two options for this which requires a 20% increase in train time and four additional DMUs. Option A offers Leven two trains an hour via the longer Dunfermline route, whilst option B offers a less frequent but faster service with one train an hour via the Kirkcaldy route.

Some of the additional units will be released from electrification schemes. Barrhead is soon to be completed and East Kilbridge should be completed in 2025.

When the Levenmouth train service starts, three trains will be stabled overnight in Leven where there will be a small train crew depot. The service will initially be operated by Class 158 and Class 170 DMUs.

Levenmouth regeneration

Although the line’s opening date has yet to be announced, it seems likely that it will re-open close to the date of the summer timetable in May or June in LMRC’s 10th anniversary year. This shows how long it takes to justify the large cost of re-opening a railway and then to design and build the line.

It will also then be about nine years since Scotland opened its last new line, the 49km Borders Railway, to Galashiels and Tweedbank at a cost of £445 million (2023 prices). With over a million journeys a year on this line, passenger numbers greatly exceeded expectation. This has acted as a catalyst for investment and opened up employment, leisure, and passenger opportunities for those along the line.

£117 million for the 10km Levenmouth branch is not cheap, yet, like the Borders Railway, it will no doubt greatly benefit the area. Like the Borders Railway, its journey time to Edinburgh will be about an hour which is much less than the bus alternative. The rail project is also linked to other regeneration projects to attract investment which Fife Council anticipates will be equivalent to its construction cost.

Levenmouth Rail Skills Academy’s first cohort.

As Joe Mulvenna, Network Rail’s project manager, notes: “The new line will improve social and economic opportunities for people in the surrounding communities and we are working hard with local partners to maximise the positive impact the project will have right across the area.”

For Joe and his team, this project is about improving the lives of the people of Levenmouth by creating economic growth and new opportunities.

The project also recently launched its Rail Skills Academy, to give young people the skills and work experience to work in the railway maintenance sector. This ran over nine weeks and was delivered by QTS training. Around the same time, the project also welcomed 200 students over a three-day period who took part in four workshops to give them an understanding of how technology was used to design the railway and how it is being built and will be maintained.

Such initiatives are part of the project team’s objective which was “to make Levenmouth a better place to live, work and play.” Whilst the design and construction of a new railway is a demanding challenge, ultimately the real objective is to maximise the benefit to the local community. This is what railways do and all the evidence shows that Levenmouth will start to realise these benefits in a few months’ time.


Rail Engineer thanks Network Rail’s Joe Mulvenna, Kirsty Ryder, and Owen Campbell for their help with this feature.

New Trains on the Docklands Light Railway

The Docklands Light Railway (DLR) has vastly increased in size since the original £77 million line opened in 1987 with 11, 28-metre-long trains. With extensions to Bank, Lewisham, Beckton, Woolwich, and Stratford International, and trains now three times as long, it is sometimes hard to understand why it is still called a light railway. But with the delivery of the first of the latest batch of trains from CAF, designated B23, the distinction between light rail and metro has become even less clear.

First, some terminology. Currently, a DLR ‘car’ is a two-body, three-bogie, articulated set approximately 28-metres-long. Today, trains rarely run as single cars; two-car and three-car trains are the norm. This terminology is having to be revised as the fixed formation B23 trains comprise five, two-bogie cars in a fixed formation that is 86.7 metres long, 2.65 metres wide, and has open gangways between cars. Each car is slightly longer than a London Underground S stock but noticeably narrower. This configuration provides some challenges, described later.

In 2019, TfL placed a contract with CAF for the supply of 43, five-car trains. Thirty-three are intended to replace all the life expired B90/B92/B2k (hereinafter B92) fleet with the additional 10 trains being used to support the projected passenger growth across the DLR network. In June 2023, TfL called off another 11 trains to further respond to growth in East London.

B07 car to be retained – foreground, B92 cars to be scrapped – background.

TfL is expanding Beckton depot to accommodate all 54 B23 trains, a net increase of 23 trains over current capacity. Moreover, maintaining an 86.7-metre train needs different facilities from those set up for 28-metre cars and visitors to the depot, who’ve arrived at from Gallions Reach station, walk past a significant building site where additional sidings are being built. There will also be an additional maintenance shed. But this article focuses on the layout and technology of the new trains based on a visit by Rail Engineer in September 2023.

Relationships

Project engineer Phil Shrapnell from TfL, together with Dave Collins and Andy Slade from Keolis Amey Docklands (KAD), hosted the visit and it was immediately obvious that they are an effective team.

Moreover, they paid tribute to the excellent working relationship with the CAF engineering team. Phil said that following contract placement there was a great deal of team building and co-operative liaison with CAF in Besain, Northern Spain, before Covid caused everyone to work remotely. The relationships built before lockdown helped effective remote working. Representatives of KAD’s Passenger Services Agents (PSA) also had input, in Spain, to the layout of operator touch points. But this cooperation went further. Phil explained that the specification was treated as a live document, with collaborative discussions between the London and Spanish teams to understand the real intent behind the requirements, allowing the evolution of the design to best meet the needs of the DLR.

Technology

Modern trains are complicated. Most of their systems are linked together by a computerised network, generally known as Train Control and Monitoring System (TCMS). On B23 it is linked to a shore system, a CAF system called LeadMind, which collects data for remote condition monitoring and can control some aspects of the train, an example being the bogie-mounted wheel flange lubricators. While all the trains have wheel flange lubricators, no one yet knows how much lubrication will be needed until all the trains are in service. But not to worry, Rail Engineer was told, the lubricators will be remote controlled from the control room.

Another new technology feature is a WiFi antenna in each car. This is for direct connection to a ‘phablet’ device using the Android operating system. These devices will be provided to PSAs who will be able to deal with passenger incidents and talk to passengers from the phablet if, for example, crowding makes it difficult for the PSA to move through the train to the location of the alarm.

Table 1

The train

The disposition of key equipment is shown in Table 1. In practice cars D and E are mirror images of cars one and two. Table 2 shows the manufacturers of key equipment and Table 3 compares weight and capacity of the B23 trains with a three-car B07 train.

Achieving weight targets was very important as there were strict limits on some of the structures from the original ‘light railway’. Although a great deal more equipment is fitted, particularly air conditioning, and passenger capacity is higher, weight has been held in check by the switch to aluminium car bodies instead of steel used on earlier trains.

Equipment

But onto other more routine technical features. Phil emphasised the importance of redundancy and graceful failure to avoid service disruption. A stranded train that needs recovery causes much more disruption compared with one that can limp home to depot. As an example, although there are three motor cars, just one of them has enough tractive effort to propel the train up the steep gradient between Bank and Shadwell. And each motor car’s traction package has two inverters, one for the two motors in each bogie. All three motor cars have their own power collector shoes which are an improved version of the Brecknell Willis design used since DLR started. There is no power bus line. Cars B and D are each fitted with an auxiliary power converter providing three phase AC power and 110V DC for battery charging, powered from Cars A and E respectively.

Regenerative braking will be the norm but there is a naturally cooled rheostatic resistor on each motor car for conductor rail gaps and any part of the line that are not receptive for regenerated energy.

Each axle has a single brake disc controlled by Knorr Bremse’s EP2002 system. Wheelslide protection is fitted which Phil expects to be evaluated on the WSPER rig (Issue 176, July 2019) prior to service.

Table 2

CBTC equipment is fitted to the trailer cars. It is the latest Thales ‘SelTrac TOP’ VOBC (Vehicle On-Board Computer). The tachometers feeding the VOBC are fitted to the eighth and thirteenth trailer axles and the antenna for transmitting/receiving data to/from track loops is adjacent. Either VOBC can drive the train and the system can switch between them seamlessly.

Unusually the tachometer axles are only braked if an emergency brake is demanded. SelTrac systems can be prone to losing position if slip/slide is detected on the tachometer fitted axle in low adhesion conditions, leading to an emergency brake application and the VOBC reporting that it is ‘lost’. When this happens, the PSA has to drive the train manually at slow speed over two loop crossovers to re-establish location, causing delay. The unbraked axles are expected to significantly reduce this issue. The guaranteed emergency brake rate is 1.26m/s2. This is the value that the ATP assumes when determining how far a train may move towards another train or obstruction.

Train control

As mentioned, the TCMS is responsible for most non-vital train control functions with hard wire control of vital functions. DLR decided that there would be two networks, one for train control functions, and a second that deals with passenger facing systems. DLR specified that the control room would have access to the on-train CCTV and was concerned that the bandwidth required for video signals could harm the response of train control commands – hence the second network.

Passenger, interior and PSA features

A big improvement for DLR passengers is air conditioning. Each car has a roof mounted air conditioner pack, and, for redundancy, given there are no openable windows, each pack has two chillers fitted. Lighting is by LEDs and each car has its own controller which can adjust the lighting level depending on the amount of ambient light and can change the colour temperature of the light depending on time of day. Each car has its own battery for emergency lighting built into the controller.

In the interests of maximising capacity, all but eight seats on the train are longitudinal, but eight transverse seats were retained, four at each end, partly to provide a semi-enclosed space for the PSA when driving manually (although they drive standing up at their request), and partly for people who like to imagine they’re driving!

There are 12 sets of passenger doors per side, two per side on Cars A, C, and E, and three per side on Cars B and D. Phil described them as low-profile plug doors which incorporate sensitive edges and anti-drag systems. They don’t close completely flush with the bodyside and, when open, project very little. When the doors are released, lights over the doors glow green and they flash red when the door close command is sent.

Table 3

There is a PSA door control at every doorway, and, following human factors review, they are located at a lower level than on the older trains with half on the left and half on the right. At stations, doors are released automatically by the CBTC. The controls are the same as the older trains: close all doors except the PSA’s, reopen doors, close PSA’s door, and public address. A key-operated switch and a microphone complete the controls.

As well as a light provided on the older trains indicating that the train has movement authority (CBTC speak for a green signal!) the B23 has a countdown indicator allowing the PSA to initiate the door close sequence a little earlier. Once all the doors are proved closed and the VOBC has movement authority, the train starts automatically. Currently, the system is set up so that the doors only close after a three-second alert has elapsed. This is compliant with the Rail Vehicle Accessibility Regulations (RVAR). But it is a much longer delay than is used currently on DLR and on most of the Underground. As the shorter delay has been used successfully on DLR for over 30 years, a proposal has been made to DfT for a derogation from RVAR, like those previously granted for some of the Underground’s new trains.

Gangways

DLR has 40-metre radius plain curves, 40-metre radius back-to-back reverse curves on the service lines, and 38-metre radius curves in the depot. Providing a gangway on 17-metre-long, two-bogie vehicles, that must negotiate such small radius curves/reverse curves is a challenging requirement and, as a result, it is much longer than is usual. It was made by gangway specialists Hubner, based on a design previously used in Frankfurt, and the project team reported that it is performing well during network testing.

Completed B23 train in CAF’s Besain factory. Key items labelled.

Passenger alarm, CCTV, passenger information

Passenger alarms are fitted in each doorway and alongside each wheelchair bay. As is usual, the passenger alarm only stops the train immediately if it is at or departing from a station. Operation of the passenger alarm alerts the PSA and the PSA can respond using the phablet or control point handset if the PSA is unable to move down the train to the customer. Passenger information includes the usual voice and visual displays. The visual displays are LCD type for the interior and LED dot matrix for the exterior and the whole system is pre-programmed with the usual messages (e.g., next station and destination) which can be varied from the control room via the 4/5G/wifi comms link. This includes the ability to display the standard TfL ‘rainbow’ board highlighting any delays on other rail lines. Additional displays are provided for advertising.

Saloon CCTV is fitted as well as cameras providing views from the front and rear of the train. The saloon CCTV cameras give views of the entire train and particularly of people using the passenger alarms. A nice feature of the forward/rear cameras is a rearwards view is displayed on the PSA’s control desk if reverse movement is selected (accompanied by external reversing beeps). 

Safety features – fire

The engineering process is aimed at delivering a train that is safe by design and the sub-systems described above all include safety features, but there are inevitably some risks that need specific controls. A key requirement is fire safety, especially on a train with open wide gangways. This applies to everything on the train with the objective of minimising sources of ignition and using materials that are hard to ignite, tend to self-extinguish, resist flame spread, and produce little smoke.

The train has been designed to BSEN 45545 Operation Category 4, Design category A. Operation Category 4 refers to vehicles for operation on underground sections, tunnels, and/or elevated structures, without side evacuation available, and where there are stations or rescue stations that offer a place of safety to passengers, reachable within a short running time. Design category A is for vehicles forming part of an automatic train having no emergency trained staff on board. The combination results in the toughest requirements for fireworthiness of all materials used in the train’s construction. In addition to careful selection of materials, a smoke and heat detection system is provided, linked to the PSA and the control room, and there are three fire extinguishers on each train.

Inter car gangway whilst negotiating depot curves.

Safety features – obstacles and derailment

The combination of good bogie design, well maintained track and ATP means that derailment risk is extremely low, but not negligible. Two systems are provided to help control the risk and consequences of a derailment. DLR had specified an obstacle detection system that would ensure a train would stop short of an obstruction (similar to modern automobiles’ emergency braking feature) but it soon became clear that comparatively longer braking distances for trains and DLR’s sharp curves made such a feature impractical. Instead, there is a bar fitted in front of the leading axle that, if it strikes an object that could derail the train, it will apply the emergency brakes. While this does not prevent a collision with an obstruction leading possibly to a derailment, by applying the emergency brake the consequences will be minimised. As another precaution, an underframe mounted accelerometer is provided on both ends of all cars. This will apply the emergency brake if it detects acceleration pattern that would be seen if a wheelset has derailed.

Safety features, emergency detrainment

There is a door at the end of each end car to which a folding stair can be fitted, in case evacuation away from a station is required. Rail Engineer was told that the current record for extracting the stair and fitting it to the front of the train is just under 80 seconds.

Infrastructure monitoring

Two trains are being fitted with Omnicom Balfour Beatty infrastructure monitoring systems that will provide an important subset of routine track condition information on a much more frequent basis than is currently possible with KAD’s existing monitoring equipment. The trains will be programmed onto each route as required.

Power supply

With 20-plus extra trains, DLR is planning an upgrade to the power supply. This will also support the higher acceleration rate of the new trains compared with the old ones. While the timetable will be organised around the capability of the B2007 trains, the VOBC will be able to take advantage of the B23’s higher acceleration rate to recover the timetable if there are delays. Another power issue is the proximity of live collector shoes to the platforms. Since DLR opened, covers mounted on the platform wall have shrouded collector shoes when trains are stopped in stations. The new trains’ shoes are in different positions, so DLR has provided continuous covers at all platforms.

PSA clear view of platforms

Another external interface is cameras/CCTV monitors and/or mirrors provided to give the PSA a clear view of the platforms when driving from the front of the train. As the front end design is different, the PSA will be standing up to drive (a PSA preference), although they can be seated if monitoring ATO and controlling the doors. Mirrors and/or monitors are being provided/relocated at platform ends to give the seated or standing PSA a clear view of the PTI for both new and older trains.

Operational acceptance and training

Currently there are two trains in London, being used for testing, integration, and reliability proving. The trains have to be tested throughout DLR, and the SelTrac CBTC has to be tuned to the train as its acceleration and braking characteristics will inevitably be different from the existing trains. Reliability must be demonstrated before being accepted and a 20,000km mean distance between service affecting failures is the requirement. Of course, KAD staff – PSAs, maintainers, etc. – also need to be trained. A train simulator has been provided and there will be a test rig for the new VOBCs. DLR has placed a long-term support contract with CAF, something that will support KAD with maintenance, spares and technical support.

To conclude, the October TfL Commissioner’s report to the TfL Board says that TfL is preparing for the launch of the new trains, and continues with depot enabling works, new train testing at times of closure, and preparation for testing in between passenger trains. Entry into service is forecast for March 2024. At the time of writing, the 25th train was nearing completion.

Photos courtesy of TfL unless credited otherwise.

DLR/KeolisAmey Docklands

DLR/KeolisAmey Docklands DLR is operated on a concession model. TfL/DLR owns the infrastructure and rolling stock, but it lets a contract for the maintenance and operation of the railway. The current concessionaire is KAD which has held the contract since 2014. In legal terms, KAD is the Train Operator and Infrastructure Manager for the stations, with TfL as Duty Holder for all the other infrastructure. The contract is due to end in 2025 and TfL has recently commenced the procurement process for the next concession. The changeover date is in April 2025, before all the new trains will be in service, so the handover process will have to take this into account.

Delivering Docklands Light Railway

Our companion article in this issue about the new Docklands Light Railway trains acknowledges the significant role of KeolisAmey Docklands (KAD) on the project and in delivering the DLR’s day-to-day service as Transport for London’s (TfL) Operations and Maintenance partner for Docklands Light Railway Limited (DLR), part of TfL.

TfL / DLR owns the assets and, in safety certificate terms, is the infrastructure manager for the guideway infrastructure, whereas KAD maintains the trains and infrastructure and is the train and station operator and infrastructure manager for all stations. This article discusses how KAD works collaboratively with DLR to improve the performance of the existing trains, whilst ensuring safety and maximising efficiencies on the trains that are soon to be scrapped (B90/B92/B2K – hereafter B92) and also preparing for the new trains. All this was discussed with Tony Kempster, KAD’s rolling stock head of technical services in early October 2023.

Avoiding expensive interventions

From experience, new trains rarely arrive at a convenient time to dovetail with an existing fleet’s orderly maintenance plan. Plans have to be adapted with the aim that old trains are withdrawn just before the wheels are worn down to the scrapping limits and/or just before an overhaul is due.

KAD has developed a mileage control database system to help it manage all this. In brief, the trains report their station stops via the SelTrac CBTC system. As the distance between two stations never varies, this is converted into mileage. This new process was developed to enable more accurate measurements, reduce the requirement to physically access the vehicles, mitigate any inaccuracies and enable prediction of all the vehicle mileages for their remaining life.

KAD also knows the trains that are running with wheel tyres which need to be scrapped when worn beyond limits, at what mileage that is likely to occur, and when the next heavy maintenance is due. This information is linked to the mileage control database. Depot planners know the mileage of each train duty which allows planners to organise formations (two or three cars – a car is an articulated unit with two bodies and three bogies) and duties to give prominence to trains/formations that have plenty of ‘mileage life’ left before needing expensive intervention.

“This requires careful planning using the mileage control database,” Tony reported, “and sometimes, stopping vehicles for a while, although this does put extra strain on availability.” He added that most Maintenance Tasks are now carried out on a condition-based regime.

Implementing condition-based maintenance was a significant change which included assessing the assets’ baseline condition, changing all maintenance task instructions (to include pass/fail criteria), transition exams, and, of course, safety assurance.

B92 type motor bogie, not longitudinal motor driving both axles.

But there is still a complex scrapping plan which, as well as taking account of the heavy maintenance needs, includes managing small wheels, bogie frame cracks (see Case Study Bogie Frames), auto coupler reliability restrictions, and some units with general reliability issues which Tony described as lemons.

An example of a condition-based maintenance activity introduced recently is extending the overhaul life of B92 traction motors; DC motors mounted longitudinally in motor bogies driving both axles. To justify postponing motor overhaul on trains soon to be scrapped, Tony identified that the biggest risk is failure of motor bearing. These carry the load of a heavy armature as the only suspension the motor sees is its resilient mounts on the bogies and the resilient wheels.

To manage this risk, KAD has adopted vibration monitoring of the bearings using the novel approach of rotating the wheels on the underfloor wheel lathe and measuring acoustic vibration in the bearings. For these cars, with just two traction motors/motor bogies, this is a fairly straightforward process.

Tony expanded on general reliability issues. B92 trains are between 23 and 33 years old. They use DC chopper control and other electronics which are life expired or obsolete. The electronic modules are connected to the train wiring with connectors that have suffered general wear and tear. This means that maintainers are often faced with difficult failures that could be a defect with an electronic module, a connector, or with the wiring. Given the life of asset, some of these problems are intermittent and can sometimes lead to challenging repairs or repeat defects with the train failing again. 

B2007 trains

As the B2007 trains will remain in service for some time – they are about 15 years old – Tony reported that a lot of new, exciting projects are coming up mainly focused on maintaining and improving the fleet’s performance.  These include replacement of obsolete systems, software updates, and installation of new systems. Tony illustrated one example – the Smart Oil Plug®. Unlike B92, B2007 cars have two motors per bogie (four per car) mounted parallel to the axles and driving the wheels through double reduction gearboxes. The Smart Oil Plug, powered by Transmission Dynamics, replaces the conventional oil filler, or drain plugs, designed and certified for axle-mounted operation to monitor temperature, vibration, and ferromagnetic oil debris – an indication of gear or bearing damage.

This wireless, sensor-based solution, developed by industrial data experts Transmission Dynamics and brought to the market by distribution partner ZF Aftermarket, enables real-time monitoring and analysis of gearbox health and behaviour in railway vehicles. The sensor can detect gearbox vibrations, providing insights into gearbox quality, wheel slide, track quality, impending bearing failure, and suspension defects. The plug, equipped with an onboard battery, transmits data to the control unit via Bluetooth and has a three-year battery life.

The control unit sends live data to a web portal through GSM, allowing ZF Aftermarket to provide KAD with real-time access to all data and alerts regarding adverse conditions. Additionally, the system offers longer-term condition monitoring recommendations to assist in maintenance planning.Currently, said Tony, the system is being evaluated to build up a picture of what the system is reporting and the results/alerts are being calibrated/correlated. ZF Aftermarket and Transmission Dynamics will be working with KAD to develop artificial intelligence to filter data and identify negative trends.

Integrating the new trains: Tony returned to the subject of new trains. He praised the team effort involving KAD Stores, Production, and Engineering Teams working well with the DLR Rolling Stock Replacement Project (RSRP) team.

Materials

It’s not just the new trains that will squeeze available space until the old ones are scrapped. The same is true of the stores. Additional storage is being created both off-site and on by obtaining 16 shipping containers. Tony added that slow moving B92 stock has already been moved into four containers which have been relocated to the new build area, freeing up depot space for building works/expansion. KAD is also in the process of clearing the materials located in the wheel lathe to allow work to begin expanding this location.

KAD is working with RSRP to develop and integrate new agreed processes to manage and, where necessary, segregate maintenance spares (exam kits), from warranty spares (owned by the supplier), customer owned materials (spares held in reserve but only obtainable with the main build), and new special tooling.

KAD has identified what parts can be salvaged from early scrapped B92s for possible use on trains to be scrapped later, i.e., items where the float is low or where they may avoid re-ordering. It has also identified 31 parts in common with B2007 parts (but inevitably not the same part number) and is working with London Underground to see if any components could be used across the tube fleet. The stores team is continually reviewing and monitoring stock levels to realise any efficiencies.

Google Earth view of Beckton depot showing expansion areas.

Staff

A number of new positions have been created to support RSRP such as project managers, commissioning technicians, material controllers, engineers, technical authors, and planners.

Tony talked about the importance of integrating the depot works with the introduction programme. The creation of more sidings on the north and south sides of the Beckton site gives a false sense of security as the construction sites are currently entirely separate from the depot. But when they start work on the maintenance shed, which will be in the middle of the depot, KAD Management will have to ensure everyone’s safety (KAD, TfL, DLR, CAF and various construction contractors and sub-contractors), whilst co-ordinating activities so that maintenance can continue to be carried out and a full service provided.

Tony illustrated this with preparations for wheel lathe works. Currently, around 28 metres is required either side of the wheel lathe to accommodate a car. But the new trains will need three times the amount of space each side and, Tony said, they are working with DLR to acquire a double headed wheel lathe to speed up reprofiling on a five-vehicle unit. Tony reported that a series of three-week part shutdowns is planned but this will need careful management as the wheel lathe road is not just used for tyre turning, but also for vibration analysis and graffiti removal.

New concession

The final part of the jigsaw is the retendering by TfL of the concession. The planned date for the new concession to start is in April 2025, before the depot upgrade, introduction of new trains, and scrappage of old trains has been completed – not the steady state usually sought for such changes. Tony stated that it’s a very exciting project at KAD, with the B92 cascade, B2007 reliability projects, new fleet introduction, and re-franchise. He reported that KAD is working closely and collaboratively with DLR to ensure that KAD’s work packages are delivered in the appropriate time.

It was good to see KAD’s plan for managing the introduction of the new trains while keeping the existing fleet running. No doubt there will bumps in the road during this process and Rail Engineer wishes success to everyone involved.

Case study: Bogie frames

In 2014, what proved to be fatigue cracking was observed in the B92 bogie frames. This led to a programme of NDT and repair which is still in place today. The root cause of the cracks was fatigue in both the parent metal and welds in high stress areas. The initial repair was by welding. However well they’re carried out, welded cracks in high stress areas are likely to fail again, but they buy time. By 2018, KAD was struggling with both vehicle availability, spiralling costs, and extended and forced delays to the bogie overhaul due to these cracks. More intrusive weld repairs followed but further cracks were found.

Something had to be done and DLR / KAD engineers started work to ‘reverse engineer’ brand new bogie frames with an independent subject matter expert to provide options for an internal strategy paper and a technical specification for the project.

The original design, detailed on a suite of drawings provided by OEM BN Bruges (part of Bombardier) was converted into a 3D model from which 2D drawings were produced. The specification proposed the following changes aimed at improving frame design and manufactured quality:

  • Pre-production frames would be built and the experience would be used to simplify manufacture and allow the supplier to use current best practice.
  • The supplier would propose improved weld details at the transom to side frame joint, which was the site of the most serious cracks, and that several unnecessary pipe clips would be omitted.
  • The supplier would be invited to propose any other detail improvements that it would like to implement, provided that a justification can be offered for each one.
  • The bogie frames would be fabricated in accordance with the requirements of the railway vehicle welding standard BS EN ISO 15085, instead of standards applicable to general fabrication welding used previously. Railway vehicle welding standards were developed in the period 2005 to 2007 to improve the quality and consistency of safety critical components such as bogie frames.

As owners of the vehicles, DLR initiated this work as a project at the end of 2018 and it was agreed that it would be managed by KAD. Several companies experienced in making bogie frames were interested but, after a procurement process involving rigorous technical evaluation, Hutchinson Engineering Ltd from Widnes was the preferred supplier. Hutchinson specialises in telecoms (antenna towers), renewable energy (wind turbine towers), and other major steelwork projects and was able to demonstrate state of the art machinery, technology and quality in design, fabrication, welding, and inspection. As Hutchinson was inexperienced with railway safety assurance, SNC-Lavalin (now AtkinsRéalis) was appointed to carry out independent assurance checks and surveillance visits when production started January 2020. The first batch of new frames (10 of 40) was delivered in March 2020 and the first nine frames (3 x vehicles) were subject to additional assurance measures/in service checks in place. A total of 130 frames has been ordered, 124 delivered, and, of these, 118 have been fitted. Just under 30% of the old frames remain crack free, and about 28% of the old frames have cracks being managed through the NDT programme.

Image credit: Malcolm Dobell / Tony Kempster

The new train on the Piccadilly line will arrive in 2025

Rail Engineer described the outline design of London Underground’s forthcoming new Piccadilly line trains (2024 tube stock) in issue 190 (June/July 2021). Since then, Siemens or TfL have occasionally issued press releases showing progress with first bodyshells or mock-ups.

On 1 August 2023, Siemens announced that the first complete train had arrived at its 44-hectare Test and Validation Centre in Wegberg-Wildenrath from its Vienna factory, ready to start type testing. In November, Rail Engineer visited Wildenrath to try out the new train. It had been positioned on the inner test circuit, a dual gauge (standard/metre) oval 2.45km long, equipped with overhead line, underneath contact third rail, which had third and fourth current collection rails added for 2024 tube stock.

This article focusses on some of the train’s technical details, and the result of turning 3D renders or mock-ups into the real thing.

To recap, this is a nine-car train with bogies under five of the cars with the other four cars supported between them. The design allows all double doors, walk though gangways, and air conditioning: all passenger facing features that were the raison d’etre for this innovative design. Compared with a conventional seven-car train of the same length, it is lighter and, with just 10 instead of 14 bogies, there is more under-floor space which was vital to accommodate air conditioning equipment.

Collaboration

When Rail Engineer interviewed Dave Hooper, Siemens Mobility’s Director of Major Programmes, in 2021, he was full of praise for the way in which the Siemens and TfL teams worked together. Two years on, Dave, together with Sambit Banerjee, joint CEO Siemens Mobility UK, Stuart Harvey, chief capital officer TfL, and Steve Ristow, head of delivery, Fleet Introduction, paid tribute to the ongoing close collaboration and the objective of delivering a train that meets all of TfL’s aspirations on time and to budget.

This year, Rail Engineer has attended several events where collaboration was seen as the solution to problems or the way forward. Occasionally, as here, collaboration has been baked into the relationship from day one, with obvious benefits to the project.

TfL Chief Capital Officer Stuart Harvey and Siemens Mobility UK Joint CEO Sambit Banerjee. Image credit: Siemens Mobility UK

2024 tube stock progress

Approaching the train, two things were immediately obvious. First, it looked awfully small set against European gauge trains, especially double-deckers. Second, there were red light strips glowing above each closed door and a green strip above the open door. The red strips stayed lit when moving which, Rail Engineer understands, is not the final configuration. Stepping into the train led to more surprises. The lighting – all LED from Yorkshire-based LPA Lighting Systems – was bright, even in daylight. Very unusually for a tube train in the open on a cold November day, it was warm, and the designers have managed to provide more headroom, no mean feat within the tight gauge of the London small gauge lines.

Inside, it is clearly a tube train with traditional painted poles and rails and a new moquette design (named Holden, a tribute to the architect of many Piccadilly line stations). Details from the original Priestman Goode proposal from many years ago survive, including a metal TfL roundel on each seat riser. The small windows, provided to allow space for air conditioning ducts, echo the 1938 tube stock and there is a particularly neat looking circular LED lamp surrounding the grabpole in the centre of each doorway. The seats are all longitudinal with some tip up seats in every car. The seats have been designed to encourage people to sit upright, but it would be an exaggeration to say they are soft; they offer a similar level of comfort to most modern tube train seats.

Above the windows, where one would normally find cardboard adverts, there were LED screens which on this train were showing journey progress towards Heathrow Airport. External information displays are white LED strips.

The train had been rigged for dynamic testing to demonstrate acceleration and braking functionality along with noise and vibration trials. This meant that only the leading car was completely clear of test apparatus and wiring; the rest of the train was closed off by a mirrored door.

Another feature is wide doorways, although the individual door panels themselves are not as wide as on previous tube stock as the door operating mechanism is in the roof, not on the car side. These are equipped with sensitive edges, similar to the provision on the most recent TfL tube trains.

There is a small ramp down to the cab.  Piccadilly line drivers will find their ‘office’ more spacious than their current cabs. As the driver sits further back from the windscreen for both comfort and crashworthiness reasons, the field of view is a little more restrictive, so some alterations to signals will be necessary for this reason and also to accommodate the longer train (113m, compared with 1973 tube stock at 106m).

From the outside

Looking round the outside of the train, the prominent white marker strip light around the cab front is supplemented by two extremely small but very bright headlights. TfL has also departed from the traditional Wedgelock mechanical coupler in favour of a Dellner type for emergency and recovery use. There is not enough space above the coupler for the usual centre anti-climb buffer, and side anti-climbers are used instead. Safety arrangements at Wildenrath precluded a detailed look underneath the train, but the inside frame bogies were clearly visible showing Brecknell-Willis shoegear, Faiveley brake cylinders, solid stick wheel flange lubricators, and wheel/rail sanding applicators.

All the bogies carry shoegear except the motor bogies on car five in the centre of the train. It was also possible to see the large centre coupler that connects a bogie car to a bridge car. The couplers are designed to allow roll, pitch, and yaw movement. If roll was uncontrolled, the intermediate car would be unstable, so one end had a roof level lateral control rod connected to the adjacent motor car. The tray supporting the compressed air supply and the many electrical connections is supported by the coupler. As the couplings do not have to accommodate lateral or vertical relative movement between cars, gangways are relatively short. This configuration has led to some clever equipment layout solutions involving shoes on all but the centre motor car, whilst the inverters (one per motor) are on the intermediate (bogieless) cars as the diagram illustrates.

Siemens’ climate chamber has been used to assess the performance in extreme weather conditions. It delivers realistic and repeatable climate conditions with which to assess whether the air conditioners cool, heaters heat, and whether all the equipment continues to operate in hot, cold, dry, wet, and freezing conditions. Tests focused on the effects of extreme ambient temperatures from -15°C to 40°C, solar load of 600W/m2, ice, and high wind speeds of up to 100kmph, to check the train can still operate in extreme weather conditions. Monitors were used to understand what passengers would experience, measuring humidity and temperatures in the cars.

The ride around the inner circuit was smooth and quiet. Rail Engineer thought the train was riding on air suspension before remembering it uses rubber springs. Overall, it is a compliment to say that this first train is a faithful realisation of the design concepts, with an overall feel of solidity.

Image credit: Siemens Mobility UK

Programme

Sambit Banerjee and Stuart Harvey outlined the programme for the next few years. Following type testing at Wildenrath, the first train is expected to be delivered to London (through the Channel Tunnel) for infrastructure integration testing in summer 2024, with entry into service due in 2025. Stuart said he expected to be able to withdraw the last 1973 tube stock train in 2027, and the last new train might be delivered a few months later. Although the original contract provided for about half of the trains to be made at the new facility in Goole (issue 104, September/October 2023), Sambit indicated that a higher proportion might be made there depending on meeting delivery timescales for TfL.

The first carbodies are due in the UK in March 2024 when manufacturing will commence for the Piccadilly line trains at the Goole factory. For further support, work has just started on a new joint venture parts warehouse on an adjacent site.

What next?

Stuart Harvey explained that the Bakerloo line trains (1972 tube stock) are even older that the 1973 tube stock, and whilst safe, are increasingly suffering from poor condition and obsolescence. He said:

“The most important thing now is that we are making the case to Government for the vital long-term capital investment we need to continue with improvements like this, which support jobs and economic growth. We want to follow the introduction of these new trains on the Piccadilly line by doing the same on the Bakerloo line, replacing the 51-year-old trains that it currently operates, and by continuing to modernise our fleets and signalling to make sure they remain safe and reliable. Such vital improvements will not be possible without continued capital investment from the Government from April 2024.”

Sambit Banerjee added that that all future UK orders including the Bakerloo line trains would be built in Goole.

Even if ordered immediately, Rail Engineer understands that none would be in service before 2028, by which time the 1972 tube stock would approaching 56 years old, an unenviable record for trains in front line daily operation. This is about 20 years beyond their original design life for which there is no real precedent, making it hard for engineers to be confident that the trains can continue running.

If nothing is done, the Bakerloo service will gradually decline. Although TfL has identified an option to carry out a costly condition improvement programme, which would extend the life for another 10 years, the costs are uncertain and new trains would have to follow. It is an expensive option compared with new trains.

Stuart explained that the current contract has a costed option for new Bakerloo line trains which must be exercised by the end of 2026, adding that TfL is seeking £500 million from government to support its capital programme. Although 2026 is the latest date for ordering the trains, Stuart said that TfL needs the go-ahead as soon as possible as extensive infrastructure works are needed to accommodate the new trains.  These changes include:

  • Expansion of Stonebridge Park Depot to accommodate more trains and this train design where it is not easy to split the train into individual cars.
  • Station works to fit new CCTV cameras and transmission system to give a clear view of the platform train interface to a monitor in the driver’s cab.
  • Works to the power supply to accommodate higher peak demand and regenerative braking.
  • Changes to the signalling to accommodate different sight lines.
Image credit: Malcolm Dobell

Conclusion

Showing off the first train of a fleet is always a good way of gauging progress. TfL and Siemens are clearly confident in the new train and by having options in their contract for more are in a position, with what is effectively an ‘oven ready project’ (to coin a phrase used by a previous London Mayor), to press ahead rapidly if funding can be made available. This funding would demonstrate confidence in London and in the East Riding of Yorkshire.

With thanks to Siemens Mobility’s Katie Byrnes for her assistance with this article.

Bakerloo line fleet, a personal perspective

I was involved with commissioning the 1972 tube stock in around 1973, shortly after finishing my training with London Transport. Thirty trains (mark 1) had been bought to replace some of the 1938 stock on the Northern line which had been dubbed ‘the misery line’. Soon after Metro Cammell said that there would be a gap in production before the Piccadilly line 1973 stock was built, so the government agreed to the production of 33 trains (mark 2) for the recently authorised Fleet line (now Jubilee line). The trains were originally put to work on the Northern line allowing more old trains to be withdrawn.

Over their lives, this fleet of 63 trains worked on the Northern, Jubilee, and Bakerloo line. They were refurbished in the early 1990s which entailed being hauled across the Forth Bridge to the Royal Dockyard at Rosyth. Whilst most of the mark 1 trains were withdrawn in the late 1990s, a few were modified to work with the mark 2 trains and to replace accident-damaged cars.

The Bakerloo line contains a large number of small radius curves and constant operation over these gives the running gear, bogies, underframe, couplings, etc, a hard life. By the time they were about 40 years old, it was apparent that they might have to keep running until the 2020s and it was my team that proposed a series of repairs to keep them going.

Authority to carry out mechanical repairs to the body and underframe was granted, although the sum had to be increased as the vehicles were in a worse condition than had been found during the initial survey (issue 141, July 2016). Since then, further modifications have been carried out to comply with the Rail Vehicle Accessibility Regulations and to refresh the interiors which were largely unchanged since the early 1990s refurbishment. The works covered in the 2016 article were intended to extend the life to circa 2026.

Even if new trains are ordered immediately, there is no prospect of them being in service until about 2028. Already the Bakerloo line service has been reduced slightly because of unavailability of trains. Replacement is urgent. Could there be further life extension? Probably, but it would involve spending a lot of money on worn out parts and engineering replacements for those that are obsolete. There would also need to be continuing risk assessment to ensure the safety of these trains and it is hard to be conclusive about risk or future life when there’s little or no prior experience of running such old trains in squadron service. The risk is that there might be a significant reduction in service, or, in a worst-case scenario, the Bakerloo line has to cease operation altogether.