For many years TfL have run an investment programme grandly entitled ‘World Class Capacity’. Its worthy aim was to introduce a frequency of trains on the Northern, Jubilee and Victoria that could be considered world class.

This generally meant running 36 trains per hour (tph). As the years have gone by the objectives of the programme have been diluted with only the Victoria line achieving its original aims – an achievement it has only now (November 2019) finally achieved. We look at the programme, what it did achieve and to what extent outstanding items are expected to come to fruition.

Call it Railway Systems Enhancement

The original ‘World Class Capacity’ programme has now been absorbed into a new programme called ‘Railway Systems Enhancement’. Whilst we at LR Towers are generally cynical in the way TfL renames programmes (and so makes progress on them harder to follow), this renaming does make a lot of sense. As pointed out in the Programmes and Investment Committee, the new name contains ‘less hyperbole’ – a trend we hope is encouraged. The remaining aspects of the diluted programme certainly did not amount to ‘world class capacity’ on the Northern line and it was questionable if the term was still appropriate for the Jubilee line.

The other main reason for the ending of the World Class Capacity programme as an independent programme was that it made little sense to consider it in isolation as it needed to be co-ordinated with other, related, investment schemes. Most notable were the Northern line extension and Bank Station Capacity Upgrade.

Making some sense of it all

One of the problems for outsiders (like ourselves) attempting to make sense of TfL plans for the Underground is that we see a spread of objectives and target dates but we do not always understand the challenges that may lay ahead. When target dates are not met, sometimes by a number of years, it is easy to be both critical and cynical. This is especially true when not only are target dates quietly changed without explanation but the objective itself is quietly watered down. Moreover, the project is generally miraculously shown, once more, as being on schedule.

The latest Programmes and Investment Committee Agenda which was published back in October 2019, starts to provide some explanation as to the current problems that TfL have in meeting target upgrade dates on the Jubilee and Northern lines. The biggest giveaway is in part of paragraph 4.1.3 where it states:

With the signalling supplier committed to delivering works for a number of other programmes and the need to progress those works in a particular order, it is expected that the signalling software update on the Jubilee line will be delivered in time to support a frequency uplift on the Jubilee line in mid 2022.

Sad to say, as we shall see later, around one month after that committee meeting we have serious doubts as to whether that 2022 date could still be met.

The “other programmes”

Quite why TfL don’t clearly state what the previously stated “other programmes” are is a mystery since they often tell us how they are committed to transparency and openness. In any case, it is pretty obvious what the two major ones are.

The first is Four Lines Modernisation resignalling. TfL committee members have been told a number of times in the past that this is an absolute priority. Given that Thales is supplying signalling to this and that they also supplied the Jubilee and Northern line signalling, it is not hard to deduce that any delays with resignalling the sub-surface railway is going to have a knock-on effect on the Jubilee and Northern lines.

The second programme that obviously must take priority over any further Jubilee line resignalling is the Northern line extension to Battersea. Now, technically, this is not being resignalled, since it is new and has never had signalling, but this needs signalling installed and the intention is to install the latest flavour of the Thales’ CBTC automatic signalling system as found on Four Lines Modernisation. Note that this will not be quite the same as what is currently installed on the Northern line so there will be compatibility and transition issues but these should be minor in nature.

The critical signalling path

Whilst a lack of money for future projects is almost certainly the main factor delaying improvement and enhancement of the Underground, the lack of signalling resources for a truly modern Underground seem to be a close second. What is generally not appreciated is just how much of an issue this appears to be. With reports, subsequent to the committee meeting, of the next phase of the Four Lines Modernisation resignalling being delayed yet again, it seems that this is becoming more critical and it is getting to the point where it may be delaying upgrades over many Underground lines – in fact practically all of them with only the Victoria line appearing to be immune.

At present there appear to be only two signalling suppliers who can provide products that can cope with the rigours of the London Underground and it is clear that neither of these work ‘out of the box’. Or to be more accurate, both companies’ products work well in situations that have already been encountered elsewhere, or on the test bench, but become extremely problematic in a new scenario in the real world.

Current signalling suppliers

Siemens supplied the signalling for the Victoria line. They are also supplying the signalling for Crossrail in the central tunnel section. One big advantage in having Siemens supply a system for the Victoria line was that it was at the time the only system they were supplying in London. This meant that the project wasn’t competing locally for resources. It also meant that a delay to the project would not have impacted on any other project.

It is notable that Siemens refused to tender for the contract for Four Lines Modernisation resignalling which effectively made Thales the only viable bidder. The reason given for this was that Siemens realised that signalling the central section of Crossrail (for which they had the contract) was going to mean they would be too stretched if they won a bid for another large project.

Thales have supplied a number of versions of their current system to TfL. The original one in London was on the DLR. The Jubilee line followed on from that. Both of these implementations were very protracted as new problems were encountered.

In contrast the Northern line only posed a couple of major new challenges for Thales (a single track branch and a loop) and was installed relatively easily as they were effectively installing a system that (after a lot of debugging) was known to work. Thales are currently working on the major job of installing the latest iteration of their system on all of the Circle, District, Hammersmith & City and Metropolitan lines (the Four Lines Modernisation) and it is understandable that neither they nor TfL want them to be distracted from this task as its successful implementation will reap huge benefits. The trouble is that the Four Lines Modernisation is not due to have all the work installed before 2021/2 (and the project is slipping) which means that signal engineers are unlikely to start to become available before 2021. More worryingly still, the resignalling appears to be slipping at every stage. If the pace of implementation does not pick up it will be many years before all the work is complete.

Northern Line – recent history

The Northern line upgrade was originally proposed to take frequency to 36tph on most of the Northern line. This proved unaffordable which was not just down to the usual factors, such as the cost of new trains and beefing up the power supply, but also the considerable cost of providing sufficient stabling for all the extra trains needed. A more modest project that would generally provide around 30tph was substituted. This was to be carried out in two phases and a first phase would see 24tph on both sections through the central area and 32tph down to Morden.

In order to gain early benefits, phase 1 was further split with the relatively easy objective of 24tph (30tph to Morden) being its initial goal. This involved resignalling and some other works but no new trains. The seemingly simple enhancement to further increase the service to Morden from 30tph to 32tph then appeared to be very problematic and the goal then got reduced to 31tph.

One might think that the above objective could not be reduced any further without becoming meaningless but the latest papers show that 31tph actually means 31tph for just one hour in the morning peak and in one direction only. Thus the much-vaunted 30tph to 32tph has now become 30tph with a single extra train in one direction fitted in morning peak. Oh, and the proposed date of introduction has slipped even further. It now intended to introduce this extra train in 2021.

Phase 2 of the upgrade to the Northern line was cancelled. This was largely dependent on a project called Jubilee and Northern Additional Trains (JNAT). As this phase will no longer happen, it doesn’t seem as if there will be any significant improvement in frequency on any part of the Northern line in the next few years.

Where did it all go wrong?

Clearly a lot of the failure to improve the Northern line is down to the cancellation of additional trains. But that isn’t the full story and just about everything else can be explained by the lack of availability of Thales signal engineers.

The first problem seems to have been when the Northern line was resignalled for 30tph down to Morden it turns out that 30tph was really all that it could do. Given there were sufficient trains, if they could have run 32tph then surely they would have done so.

We now know that they can’t even get up to 31tph (one extra train) without a signalling upgrade, some extra track work (now done) and a power upgrade. They also need to install a wheel lathe at Morden depot so that an extra train is freed up by avoiding the need to send trains elsewhere to have their wheels reconditioned.

There have been continual suggestions by staff members on the District Dave website that Thales never really finished the job properly on the Northern line. Yes, it works for 30tph but there are still a lot of annoying non-critical bugs and there is no coasting feature – which is not essential but is nice to have and reduces heating in tunnels. It would not be unreasonable to believe that part of the reason for the work never being fully completed is that signal engineers were re-prioritised to work on Four Lines Modernisation.

The second problem is the one mentioned at the start with other projects taking priority. It seems that the idea now is to add the one extra train in the same timetable as the one that will be introduced on the opening of the Northern line extension to Battersea in Autumn 2021. The idea appears to be to optimise signal engineering resources by doing the work at the same time. Another factor could be not wanting to increase capacity down to Morden prior to temporary closure of the Bank branch (as part of the Bank Station Capacity Upgrade works) in order to reduce the number of passengers disrupted by this closure.

A possible reason for failure to implement 32tph

There is now some evidence that points to why the objective of 32tph from Morden has been abandoned for the foreseeable future. It appears that the signalling on the Northern line cannot currently handle 32tph due to the control units in the signalling system not being up to the job. However, the units are obsolescent and so already out of date and the more recent ones (as being installed during Four Lines Modernisation) would be able to handle this. An upgrade would be relatively cheap in relation to overall signalling cost and it makes the system easier to maintain but it does cost money that simply isn’t available at the moment. Of course, that presumes that the necessary trains can be made available from the existing fleet but that is another issue.

A baffling question

Completely unexplained in all the plans for the Northern line is quite how London Underground are finding the extra trains needed in order to open the Battersea extension. Even with only a 12tph service it is expected that they will need the equivalent of an extra three trains.

Originally, it was glibly suggested that the extra trains (originally five based on 16tph to Battersea) could be made available by increasing availability. But the trains are maintained by Alstom and there is no sign of any agreement for them to make more trains available. All they have agreed to is to provide one extra train for the extra morning peak train from Morden – and that they wouldn’t commit to that without the new wheel lathe.

One other possible solution for making more trains available is a new turnback, which was originally in the plans, proposed for East Finchley. However, the latest papers show no sign of this project going ahead and it appears to be one of many that has been quietly dropped.

A further, less likely, explanation is that the signal engineers manage to improve run times on the line to a sufficient extent that it provides the equivalent of three trains. This is a very tall order.

As we are mystified by there being no obvious answer as to how the trains are being provided, we will scrutinise carefully any future documents for clues.

Jubilee line recent history

Like the Northern line, the Jubilee line has a history of failing to live up to its promise.

The Jubilee line opened in its present form (with the Jubilee line extension) in 1999. At the time there was considerable optimism generally that the latest signalling was going to create a huge increase in capacity and a potential capacity of 36tph was promised. As with other projects relying on a technology just around the corner, it was not to be. The system could not be made to work and a late decision was made to introduce old-fashioned tried- and-tested two aspect colour light signalling. This, inevitably considerably reduced capacity.

After a lot of difficulty, Thales was able to introduce its automated signalling which eventually led to a 30tph service on the Jubilee line in the central section from Willesden Green to North Greenwich. This was the limit of what the signalling could deliver without further modification but another factor was there weren’t any spare trains.

As with the Northern line, an order for a supplementary batch of trains was cancelled so the signalling strategy, which was to have been to upgrade to 34-36tph was abandoned and an investigation was made to see what improvements could still be afforded.

One thing that could be built on was that, prior to cancelling all work on a further capacity increase, a turnback crossing at West Hampstead had recently been renewed. With this now available for daily operation, rather than just emergency use, it was concluded that it would be possible to provide 32tph between West Hampstead and North Greenwich. The catch was that even providing this would require further signalling upgrades.

Cancellation of JNAT – a blessing?

What no-one is saying, but now appears to be clear is that it is very fortunate that the Jubilee and Northern line Additional Trains (JNAT) project got cancelled. At the time the reason given was because the budget had to be revised downward to take into account reduced off-peak income over the whole of TfL. In retrospect, it is probably just as well it was cancelled because it is now clear that the increased service could not have been implemented without major work from the signal engineers and they were all busy on the Four Lines Modernisation programme. London already has enough embarrassment of many Crossrail trains being substantially under-utilised. Having yet more new trains sitting in sidings would not go down well with the public.

Of course, London Underground could have prioritised signalling related to JNAT over Four Lines Modernisation. The problem with this is that, in terms of cost-benefit, the Four Lines Modernisation resignalling would undoubtedly show a better case – not least because the necessary trains were already bought, paid for and in service.

It then seems highly misguided for one London politician, campaigning in the election, to have a pledge to try and get the additional trains for the Northern and Jubilee line reinstated. Politicians always underestimate the complexity of railway planning and we at LR Towers would encourage politicians to steer clear of such independently-thought-out ideas. From a political perspective such proposals are rather risky. Additional trains may sound like a simple objective but many factors need to be resolved including power supply, signalling, tunnel cooling and providing extra stabling space. If any of the necessary requirements are not in place then the promises made will not be kept.

The one that got away – the Victoria line

The great exception to all the woe provided by a failure to live up to proposals is contrasted by the success of the Victoria line. One might have thought that work here was already complete with a very impressive 36tph running in at the height of the morning and evening peak. However, yet again, the Victoria line shows what can be done with sufficient investment and a determined attitude.

On Monday 14th November 2019, there was a new timetable introduced on the Victoria line. Not for the first time, the date on the timetable is not the actual date it was introduced.

To quote from the working timetable:

The 36 trains per hour peak service has been extended to run for 180 minutes (3 hours), during the morning and evening peaks. During these periods, there will be no train service between Seven Sisters and Northumberland Park Staff Platform.

It is believed that the new timetable was dependent on upgrades to the depot. The basic problem was to get the 41 trains (from a total fleet of 47) into service quickly enough between 05.00 and 07.00. In fact the last train doesn’t get out until 0733 and the true 36tph (train every 100 seconds) service does not start until around 0720 and ends at 0950. Nevertheless what has been achieved is quite remarkable.

Despite what has been achieved, there is still a need for more on the Victoria line. Recently released data suggests that, actually, it would be desirable to cater for a four hour peak period on the Victoria line. Capacity-wise it is probably not essential but it would improve comfort levels. Whilst in the evening this should not be too much of a challenge, the difficultly of getting all the necessary trains into service so early in the morning would be considerable.

More than 36tph?

Coincidentally, on the same day as the Programmes & Investments Committee met, there was a talk at the Institution of Mechanical Engineers on the subject of ‘Towards common goals for engineers and transport planners’. The speaker was Geoff Hobbs, Director of Public Transport Service Planning at TfL. He specifically mentioned the Victoria line and explained to the audience why they couldn’t run more than 36tph.

As the above slide from the presentation makes clear the limiting factor on the Victoria line is the dwell time at King’s Cross southbound platform in the morning peak. You need almost every second of the 100 seconds between trains. Unfortunately, even if you could somehow cut that to 95 seconds, you would start to get the same problem at Highbury & Islington station so, as a minimum, it is desirable to solve both these problems.

Not mentioned in the talk but a few pertinent comments:

It is presumed that Victoria station northbound is no longer such a critical problem as completion of the station works means that passengers spread along the platform more. This hasn’t increased capacity (whatever TfL have stated in the past) but has reduced dwell time.

It is also presumed that there either isn’t a problem at the termini with turnround time or that a problem that solves the issues at King’s Cross would also resolve termini turnround time.

Recovery time isn’t that important. Any delay will propagate to the end of the peak and then time can be recovered as the service starts to wind down. Nevertheless recovery time is highly desirable and shouldn’t be given up lightly.

There are sufficient trains in the Victoria line fleet to cater for an even more intensive service – especially so if ’round trip’ run times could be reduced slightly.

The critical point made here by Geoff was that if the engineers, or anyone else, could solve the problem of getting the trains, say, only 95 seconds apart then there would be great benefits to TfL and its passengers. Such a solution would almost certainly be cost-effective and TfL would be keen to introduce an even more frequent service.

No good news

Given the problems of the TfL budget and the continued delay of Crossrail, it is difficult to imagine that progress on major TfL rail projects could get any worse. Yet to this mix we have to suggest that the challenges of modern signalling, necessary in order to substantially increase capacity without building new lines, is now becoming a critical factor.

It seems that any delay with Four Lines Modernisation will impact on future improvements on the Northern and Jubilee lines. After that comes the need to resignal the Piccadilly line. This has already been postponed due to monetary constraints but the fear is that it could be further delayed by the challenge of getting a signalling system working that could support the proposed frequency (32-33tph). All subsequent projects (including the Bakerloo Line Extension) could be similarly delayed. Meanwhile, it is well known that when existing signalling continues to be used beyond its designed life it starts to fail more often leading to considerable passenger delays. For all lines except the Victoria line, the outlook is not good.