Both meaningless and meaningful, the phrase ‘driverless trains’ is a recurring one in London politics. In this piece, we explore the reality behind the phrase and what it means in a London context.
On 1st June 2021, the Department for Transport and TfL agreed a further funding settlement, with conditions. This settlement was required due to the continuing financial pressures placed on TfL by the government’s requirement that they continue to deliver as full a service pattern as possible whilst also requesting that passengers not travel. As we have written about before, this is a particular issue for TfL as successive governments have required it to move to a position where it draws the overwhelming majority (upwards of 70%) of its funding from fares.
Included among the conditions of settlement (which can be read in full here) is a requirement to investigate “driverless trains.” Something that has triggered the usual flurry of excited misinterpretation the term seems to induce. “Driverless tubes on the way” proclaims the Evening Standard, with Ross Lydall announcing that in the latest funding settlement “The Transport Secretary paved the way for the first “driverless” trains on the Tube.”
The Standard can perhaps be forgiven for falling into the trap of hyperbole, given that they are not the first to see TfL’s need for funding as an excuse to rattle out a familiar old political line. On 6th July 2020, Prime Minister Boris Johnson paid a visit to the site of Siemens’ new rail manufacturing plant in Yorkshire. In front of the gathered press, he made his thoughts known on the future of rail and the role he believed ‘driverless’ trains should play in London in particular.
“So what I will be saying to the London transport authority,” He said, “is let’s take advantage of this technological leap forward. Let’s not be the prisoners of the unions any more.”
“Let’s go to driverless trains!” He continued, then added, “and let’s make that a condition of the funding settlement for Transport for London this autumn.”
A phrase with no meaning
So just what is a ‘driverless train’? Unfortunately, the answer is: ‘it depends’. That may sound infuriatingly vague, but it is also why the phrase has gained such political currency. We’ve talked on here before about the concept of Abermankönntedocheinfach. That is, political buzzwords which make a complex concept sound simple, convey no actual meaning and leave the listener to interpret them according to their own limited, non-relevant experience or personal bias.
As you can see, it sounds better in German.
The phrase ‘Driverless trains’ is Abermankönntedocheinfach in its purest form. To one listener, it may trigger visions of a train that is entirely automated, to another it may mean something more subtle, such as the displacement of the ‘driver’ from the cab and their transition to a role similar to that of the ‘Train Captain’ one finds on the DLR.
We’ll discuss those nuances, and their relevance to London and the current situation later, but it is critical first to make one thing clear up front: Driverless trains doesn’t mean whatever you think (or rather want) it to mean. This fluidity is one of the reasons that it has retained such currency in political discourse. Whatever the listener believes ‘driverless trains’ to be will always turn out not be what the politician later claims that they meant, when they are asked to replace words with results (or rather the funding necessary to achieve them).
The different levels of ‘driverless’
This article is intended to be a useful primer on what can and can’t be implemented in London, rather than a detailed look at how rail automation works. The table below, however, gives you some idea of the different grades of automation (or GoAs, to their friends) that exist.
| Grade of Automation | Train Operation | Setting train in motion | Driving and stopping | Door closure | Operation during disruption |
| GoA 1 | ATP with driver | Driver | Driver | Driver | Driver |
| GoA 2 | ATP and ATO with driver | Driver / Automatic | Automatic | Driver | Driver |
| GoA 3 | Externally controlled but attended | Automatic | Automatic | Automatic / Attendant | Attendant |
| GoA 4 | Unattended | Automatic | Automatic | Automatic | Automatic |
Being able to achieve each of these levels of automation depends on a number of critical factors. All of these relate back to a single core principle, though: simplicity of system design.
Complexity is the enemy
Operating trains is complex. It involves a vast range of micro-calculations and micro-decisions on everything from the speed of approach or departure, to when doors should open, to how trains on the same (and sometimes other) lines should flow around each other.
Both human beings and computers are capable of doing all these things. Humans are, ultimately, just natural computers. But the more complex the decision-making required on a particular transport system, the more knowledge and calculations are required for it to be done within acceptable safety parameters.
What this means is that the more complex the transport system, the more learning required and thus the less suited it is to automatic operation. Because, at least until the invention of ‘true’ Artificial Intelligence, learning is an area in which ‘wetware’ (that is, humans) remains superior to software. Wetware learns things faster and is quicker to adapt when things go wrong. And the more complex – and the older – your transport system is, the more potential there is for things to go wrong.
The Underground, remember, is the oldest (and arguably the most complex) metro system in the world.
This isn’t to say that machine learning hasn’t progressed. Indeed one of the common ‘but surely they can…’ arguments for ‘driverless’ trains is that machine learning is advancing every day and that the railways should learn from tech disruptors: innovate first, iron out the issues over time. It is certainly true that machine learning has come on leaps and bounds, but improving train control isn’t something one wishes to do through an agile, ‘launch-first-fix-later’ development methodology on a live railway. ‘BUG: Software ignores screen resolution changes’ is very different to ‘BUG: Train doesn’t stop at crossover junctions with a different signalling system installed.’ To users, the former is an annoyance while the latter is potentially a significant emotional and life-changing event.
Climbing up the GoA levels therefore depends to an enormous degree on how much complexity you can engineer out of your underground railway. You need your train system to face as few decisions as possible, and the environment within it is operating to be as uniform as possible.
In reality, this means you aim to have a unified signalling system, unified train design, track and station layouts that are straightforward and free of curves (particularly in the stations) and a complete absence of any other control mechanisms or systems (particularly electronic ones). You also need systems in place to deal with the inevitable issues that occur when humans try to board already busy trains.
All of these are things that London lacks.
The wetware problem
As highlighted above, beyond the issue of train control, there is also a further and more serious problem to consider, should one desire is to move up the chain of automation to the ultimate level: full unattended operation. That problem is passengers.
Whatever the issues related to interacting with the laws of physics and signalling, they are minor in comparison to human behaviour. Humans always break rules. This isn’t just a rail automation problem, it’s the biggest issue facing ‘driverless’ cars as well. We commit a thousand micro-infractions – whether we see them as such or not – with every journey we make. Feet are stuck in doors, coats and bags are trapped there. We do not exit platforms promptly, nor do we always move down inside carriages.
On top of this comes the issue of safety in an emergency. If you are aiming for the highest level of automation – the removal of staff from trains entirely – then you need to make sure that in a fire or similar emergency, station staff can reach every train as quickly as possible. Yet that response time is never going to be zero, and that means you need a way to make sure that passengers who detrain themselves have somewhere safe to go.
New vs old
All of these potential issues either need to be programmed for, or the possibility of them occurring has to be engineered out. This is, for example, why Platform Edge Doors (PEDs) are a given (and in the UK currently required) for the highest levels of automation. That the DLR doesn’t have them – an example frequently waved around by Abermankönntedocheinfachists – is a legacy of it being much older than people remember. The DLR is thirty-five years old. At the time, level platforms on an almost-entirely-above-ground network were deemed sufficient enough for automatic (but note, again, not unattended) operation. But what has become apparent in the years since, particularly as DLR passenger numbers have grown, is that they are not mitigation enough to serve as an example for the Underground to follow. The DLR method doesn’t scale to support unattended operation, safely, without PEDs.
The fact is that the DLR’s right to operate the way it does is ‘grandfathered’ into railway regulations. The ORR (who make the rules on these things) have long made it clear that were the DLR to be built right now, then PEDs would be required there, too.
And this is why PEDs are so critical to any discussion of attaining the holy grail of unattended operation on any network in the UK. Remove potential access to the track unless the train is motionless, and you eliminate a huge number of potential human micro-infractions. Use much wider platforms and dispersed entry and exit points and you reduce bottlenecks. This is why the Elizabeth Line (and newer lines abroad) always have PEDs.
Similarly, the emergency access problem can also be addressed by digging bigger tunnels than were traditionally required. This is why you will always see a passenger walkway in any newly dug metro tunnel. Indeed it’s worth noting that even the DLR has these too.
Indeed designing for all of the above, geography, finances and geology allowing, is more-or-less a standard process now. Those who call for more automation in London will frequently point to newer systems in China, India or Spain as examples of what the future should be. Nor does one need to look that far away anymore. When it does open, this is why the Elizabeth Line will be able to run, fully automated, throughout its central section. There it will be running on a new railway, on new track, through new stations all designed around such operation.
Yet the wider London Underground is not a new system. It is an old one. The oldest. And whilst what has been put in its tunnels and stations has changed over the years, the fundamental structure of them has not, and will not, without an awful lot of digging things up and starting again.
This limits the amount of automation that is practical not just across the network, but sometimes across the same line. Solutions that seem simple from a macro level, fall apart when they hit the reality of a hundred years of “it made sense at the time” design. Bank station’s screeching curved platforms were seen as a necessary evil, as without them the current station wouldn’t be there at all. Yet they all but prevent the installation of PEDs – because carriages are rectangles and rectangles don’t move smoothly round a curve – they briefly overlap it.
Elsewhere in London, Turnham Green’s platforms might seem perfectly designed to accommodate PEDs, and they are. But both District and Piccadilly line trains theoretically have to use the same platform and, due to both lines being designed differently elsewhere, these services use different types of train.
So where do the PEDs go?
Do they align with the doors on the Piccadilly line trains, or the District ones? Making that choice instantly reduces passenger services by blocking the other line from using the station. Which service do you cut? And even if you solve it there, then how do you solve similar (but often slightly different) issues at Acton Town, Ealing Common and everywhere from Rayners Lane to Uxbridge?
None of these problems are insurmountable. It is perfectly possible to fully automate old metro systems. Nuremberg, Paris (one done, one underway) and Singapore (twice) have all converted old lines to full automation. They too are often held up as examples by those demanding full automation in London: “See! It can be done!”
What those lauding such conversions fail to grasp, however is the difference between an example and an exception. What they should pause to consider is this: There are over 100 metro systems in the world built before 2000. Of those, why have only four been converted to full automation?
It is the curse of Abermankönntedocheinfach once again.
Choosing your priorities
It is not our intention to try and lay out here every single problem that besets automation in London. Our goal is simply to highlight that they exist, and are legion. None are insurmountable, but they all come at a cost.
Sometimes that cost is purely financial. Re-boring the entirety of the Central Line tunnels to make them wide enough for an escape path is certainly doable, but the real cost in tunnelling and the secondary economic impact through disruption to the city during the work would run to multiple billions of pounds. Who is going to pay for that?
Then there are the many other variants on the Turnham Green problems: what do you do in areas where Tube trains and mainline trains share tracks or stations? Whose Tube access do you remove entirely, so that you can remove the staff member entirely?
The myth of the strikeless Underground
That ‘entirely’ is important to consider because one of the most commonly given reasons for getting rid of drivers is to reduce the chance of industrial action. This is consistently presented by the more vocal pushers of ‘driverless trains’ as the reason it would be worth all the money, effort and (presumably) removal of certain Tube services at Turnham Green or elsewhere. Take the cab off the train, they say, and suddenly strikes disappear.
Yet unless you are removing humans from the entire operation of the network, all you are actually doing is shuffling pieces, not removing them from the board. Station staff can strike, and do. DLR ‘Train Captains’ can strike, and do. Control centre staff can strike, and do. Signallers can strike, and do.
As plenty of mainline railway franchisees have discovered, changing the relative responsibility of the roles doesn’t shift the balance of power between employer and employee. It simply alters which Union you need to negotiate with most. Politicians who daydream about ‘busting’ the RMT seem to forget that ASLEF is normally waiting in the corridor as well, and would also like a word at some point.
Even the magical promise of ‘AI operation’ doesn’t solve this problem, if a line’s complexity can’t be descoped enough to mean that you could operate it with anything less than ‘true’ AI. All you’re doing without that is shifting the strikes from onboard the train to the centralised control centre. And hitting that highest AI level is decades, if not a century off.
Indeed one could argue that the most effective Turing Test in the world right now would be to ask a computer to successfully operate (in every sense of that word) a Metropolitan line train. It may well happen one day, but unfortunately at that point the first thing the now-sentient AI will likely do on completion of its first shift is go join a union.
Focusing on achievable goals
Indeed those who get particularly excited about the higher levels of automation often lose sight of the fact that automation is a means to an end, not an end in itself. This is something that then-Mayor of London, named Boris Johnson, made clear to Conservative London Assembly Members who demanded ‘driverless trains’ in 2010:
“I would rather prioritise capacity.” He urged. “I would rather put the investment into expanding the ability of our underground system to carry people in comfort, than in putting money now into creating a new breed of driverless train.”
Capacity, the former-Mayor stressed, should always be the goal. Not Driverless trains as an end in themselves. And capacity improvements can and are being delivered, because much of the Underground network is already sitting at GoA 2, while GoA 3 has been a goal for things like the Elizabeth line for some time.
The current situation
That last fact is particularly pertinent here. If you dig into the actual wording of the funding settlement, and ignore the cursed but inevitable cries of “driverless trains” from politicians and wider media, you’ll find that it is GoA 3 that is being talked about here:
Working with DfT, TfL will make sufficient progress towards the conversion of at least one Underground line to Grade-of-Automation 3 (driverless, but with an on-board attendant, as on the Docklands Light Railway), subject to a viable business case and its statutory responsibilities.
It continues:
To achieve this DfT and TfL will produce a Full Business Case for the Waterloo & City Line within 12 months and for the Piccadilly Line within 18 months. Progress towards this milestone during the 2021 Funding Period will be measured by the Oversight Group and will be as follows:
a. Delivery of at least interim OBC on Waterloo and City line by the end of the 2021 funding period.
b. Delivery of at least interim SOBC on Piccadilly line by the end of the 2021 funding period.
c. Market engagement into alternative platform edge protection technology, to be led by TfL and completed by 30 November 2021.
d. Design work on rolling stock specification, new signalling, and Platform Edge Doors (PEDs).
Readers will note that the the settlement either tacitly, or openly accepts the existence of all the issues we have identified so far. Remembering that complexity is, as we stated, the biggest enemy, it can be noted that the most aggressive push to “driverless” is intended to be on the smallest and least-used Tube line: the Waterloo & City. Two stations with a single tunnel. It should also be noted that the second, larger line mentioned is also not particularly surprising: the Piccadilly line. The line where new rolling stock procurement is already in progress, the launch event for which was the trigger for Prime Minister Boris Johnson to make comments about “driverless trains” that Mayor Boris Johnson had previously been on record saying were uninformed.
It should also be noted that the settlement explicitly acknowledges the current barrier (pun intended) presented by the need for PEDs, as well as (less explicitly) highlighting why they remain one of the biggest barriers to any actual implementation of even DLR-style operation on the Piccadilly line: the “Turnham Green Problem.” You can’t put PEDs on stations that serve multiple lines, where the rolling stock differs.
None of this is, however, the biggest barrier to further automation on the Piccadilly line. This is not whether Siemen’s new fleet of trains for TfL have a cab or not, or whether the DfT would like to see it or not, but the line gets the signalling upgrade it so desperately needs. This would allow both current and new trains to push beyond 30 trains per hour (tph), matching similar service levels already operational on the Victoria line and, yes, open up the line to greater automation in the process.
It’s worth noting that the current financial settlement makes no reference to this particular issue in its list of driverless issues and stated goals. An uncharitable mind might suggest that this is because, as things stand, TfL have been forced to cancel the Piccadilly line signalling project due to the lack of financial support provided by the government during the COVID crisis.
As long term readers will wryly note, once again it is noticeable that the smoke and noise about ‘driverless trains’ rarely stops to acknowledge the need for extra investment outside of the cab to achieve that end.
An old tune with no new lyrics
Ultimately, it is the last point that matters here, as the old canard of ‘driverless trains’ surfaces yet again.
The phrase itself is a siren song, meaningless and ephemeral. It sounds attractive and ‘common sense’, and is something that politicians and other Abermankönntedocheinfachists roll out when they want to sound like they’re offering a solution without actually offering one. Because they want to make it sound like the thing that the London Underground is lacking is vision. That TfL (an organisation notable for its highly fractious relations with unions and unspoken goal to have less mission-critical staff) lacks desire.
This is because vision and desire are free, and it is thus an easier alternative to suggesting things that are actually actionable, but which therefore require a commitment to cost.
The highest levels of automation are also a solution in search of a problem that they can actually fix, in London at least. As this article has covered, the sheer level of physical and economic upheaval necessary to deliver even “DLR style” automation in most places – the reboring of tunnels, the signalling overhauls, the station redesigns, closures and service reductions simply doesn’t represent value for money. Even over the longest scales. Because the issue isn’t whether you can solve some of the problems in some of the places. That’s not how Tube lines work. You need to be able to solve all of the problems in all of the places.
It is only if automation itself is the goal that a GoA 3 Underground (or above) represents value for money. Which might make one wonder why it repeatedly comes up. But remember, as we’ve covered here, talking about ‘driverless trains’ can be a very politically profitable exercise indeed, because it carries almost no associated cost at all.
Our recommendation here at LR Towers is that you remember this, whenever the topic comes up. There are far better ways to increase capacity on the London Underground – and we are talking about the Underground here, not some hypothetical unbuilt metro system at home or abroad – than ‘driverless trains’. And again, as former Mayor of London, Boris Johnson said:
“I would rather prioritise capacity… I would rather put the investment into expanding the ability of our underground system to carry people in comfort, than in putting money now into creating a new breed of driverless train.”
As can be seen, the former Mayor of London seems to have a clear grasp of the support TfL needs right now. One wonders if he could perhaps be located and encouraged to have a word with the current Prime Minister.
Whilst I’ve seen pictures of PEDS on above-ground stations in other countries. I’m not aware of such use in the UK, at Turnham Green or elsewhere. Does ‘going up a level’ always require PEDs at _all_ stations — with the issues around varying rolling stock — or just below ground level, in which case it could be less of an issue.
And so far as an “on-board attendant” they need to be fully qualified to drive / control the vehicle in an emergency anyway, so why not just, perhaps, call them “drivers” for the sheer hell of it?
I thought as it got busier, DLR experience demonstrated that the best place for a ‘train captain’ attendant to monitor doors and systems and press the go button is from the front seat row immediately behind the windscreen, especially during the peaks. If there is to be a responsible human onboard, it’s best for resilience that they have a secure space to remain safe from the worst excesses of the public somewhere in the train and can always get to door controls reliably. The traditional front cab position must to some extent reassure passengers that their driver is taking the task seriously as they would be most exposed in a frontal collision.
Turnham Green has separate platforms for the Piccadilly and District lines. Ealing Common would be a better example, as the platforms are shared there.
Turnham Green has separate platforms for the Piccadilly and District lines. Ealing Common would be a better example, as the platforms are shared there.
Yeah, I’ve broadened the example out to make it clear that’s just what it’s ended up being called here at LR Towers, rather than that being the single point of apparent failure.
Matthew: Turnham Green has separate (for most of the day but not always) platform *faces* for the two, but just the single *platform*, unless you are proposing to rebuild the platforms with a big step along the midline?
One possible way of at least partially ‘solving’ the door spacing issue with PEDS is to have doors that either drop down from above or raise from the ground though I believe experience with these has been less than satisfactory where they have been tried.
You could of course have virtual PEDs as well with laser or RF beams to detect people too near the edge of the platform. This however allows passengers to prevent train departure just by standing too close to the detection line.
Another method is to have remote monitoring of the PTI by CCTV with a remote operator pressing the clear to start button.
In terms of the political side of the discussion about driverless trains Boris Johnson stated that TfL will not be buying any more trains with cabs so I assume the apparent cabs on the Piccadilly line replacement stock are just places for 1st class passengers ?
Excellent article, but although the content makes it clear, perhaps the title should be changed to something like:
“The Right-Wing myth of the driverless Tube train” ??
The restatement of the levels of GoA #Number is very useful, especially given the, um, “misinformation” peddled in the popular press.
You made me laugh out loud: the first thing the now-sentient AI will likely do on completion of its first shift is go join a union.
John M
Rising or dropping doors is a very easy way to kill or injure people.
Perhaps not?
I know this subject is a perennial bugbear to many, but the actual announcement today seems clearer than this article suggests (at least in the beginning). It commits TfL to looking at Level 3 on specific lines; to investigate platform interface technology (i.e. acknowledging the PED challenges); and to produce business cases.
It is of course entirely possible, though hopefully unlikely, that the government will declare the current safety regulations to be “red tape” and legislate to water them down so that PEDs and walkways are no longer required for whichever level of “driverless” operation they’re ultimately keen on.
Driverless trains are a way to distract from the upcoming cuts to services.
I hope you don’t fall for it
Is this in fact the result of a clever piece of negotiation by TfL? As mentioned, they had to cancel the Piccadilly Line resignalling. The requirement to come up with proposals to “automate” the Piccadilly shoves resignalling straight back into the potential funding frontline, because, as you so rightly say, it’s as much an essential ingredient of automation as the new trains are.
The Waterloo and City is also chucked in. I don’t know if there’s any value in having a pilot scheme, but I would guess that TfL would like some more new trains and a few sets for that line would keep Siemens Goole plant going for a wee bit longer, giving them a little bit more time to persuade DfT to fund new trains for the Bakerloo as well.
Thanks JB for a good write up here.
One big advantage I see of “GoA 3” and above level trains is that it is possible to operate both step-back-style (Jubilee at Stratford, Victoria at Brixton and Walthamstow, Aldgate on the Met and Elephant and Castle on the Bakerloo) operation with having to run compilated driver-and-train patterns. I understand it that Stratford Jubliee is being done by an override of the timetable and signalling system by the signal people, which is why there isn’t any real passenger departure data at Stratford Jubilee platforms:
“Stepping back is only done between 07:19 and 22:57½ Monday-Friday, between 08:01½ and 22:57½ on Saturdays, and between 09:44½ and 19:58½ on Sundays. Outside of these hours, stepping back is not done so platform 13 is used by every third train. Also, platform 13 is used during disruption or a special service (e.g. last weekend due to closures). … [the TBTC signalling system] is told not to auto route trains into [platform 13] so it has to be an active decision by the signaller.
([Arturs Dobrecovs] has confirmed everything I have written here with a Jubilee line train operator)”
If/when the DLR gets extended to Thamesmede and Abbey Wood then this means that trains will be able to pop into one of the platforms at Beckton and just reverse out again, taking up no extra time to do this. This will make a Thamesmede to Canning Town DLR train takes as long as a normal one, unlike anywhere else with a reverse where the driver has at least to have the time to walk the length of the train.
Regarding the Turnham Green comments, at current point there are no trains timetabled on either the Piccadilly or District lines to not use their respective tracks between Acton Town and Barons Court. It would reduce the redundancy of having a 4 track section regarding signal failures, but London Underground do not have that as a priority given their recent decision to plain line the 26 points at Barons Court, meaning westbound District line trains cannot cross to the westbound fast line.
You would also not require a massive step in the platform at Turnham Green to make the platform level, instead you can adjust the height of the trackbed, as was done at Ladbroke Grove to create level boarding for the C Stocks, and only recently corrected so the height was correct for level boarding for the S Stocks.
Another point that would be interesting to raise how well the Waterloo and City would fair in a business case for automation, given as you stated it being the least used line, would there be enough of a financial incentive?
Is this in fact the result of a clever piece of negotiation by TfL? As mentioned, they had to cancel the Piccadilly Line resignalling. The requirement to come up with proposals to “automate” the Piccadilly shoves resignalling straight back into the potential funding frontline, because, as you so rightly say, it’s as much an essential ingredient of automation as the new trains are.
This is why, played right, I don’t think this part of the settlement is that bad for TfL. Any plan is basically going to say “you have to do the signalling first.”
At which point the DfT will frankly shut up about it, rather than actually shell out the cash. Won’t stop politicians banging on about it though.
Another point that would be interesting to raise how well the Waterloo and City would fair in a business case for automation, given as you stated it being the least used line, would there be enough of a financial incentive?
If, hypothetically speaking, someone had seen the numbers from the last time TfL did a Business Case on this then that someone would conclude that the W&C is actually the only line where it legitimately makes sense, if you can overcome the structural limiting issues at Waterloo itself.
Everywhere else they would likely conclude that it’s “all or nothing” at which point the absolute atrocity in cost terms of trying to convert the SSR renders the whole idea a bit silly.
At least that’s what someone would probably say. Hypothetically. If they had seen the numbers.
The government were seemingly perfectly happy to take the entire revenue risk for the majority of the national rail network but want to punish London for having a Labour Mayor. More hyperbole and BS from the incompetent class of 2019.
“Operating trains is complex. It involves a vast range of micro-calculations and micro-decisions on everything from the speed of approach or departure, to when doors should open, to how trains on the same (and sometimes other) lines should flow around each other”
Sorry this statement just doesn’t hold water-
with respect, train driving is a one dimensional job.
The number of judgements a national express coach driver or a lorry driver have to make in ten minutes in their two dimensional world are many many times more than the number of decisions expected of a train driver in his one dimensional world & also more complex, not just yes or no, but graduated.
That is why the Vic line was able to be fully automated more than 50 years ago in the pre computer age(although union controlled LT required a doorman in the front) & why scores of long metro lines are completely staffless & accident free now- all over the world except for the Union run cities of New York & London.
@J Elson
Those lines are new build if GoA4 (the point made in the article).
Most LU lines run under GoA2 – i.e. Victoria, Central, Northern and most of the Sub-Surface. If you want to go to GoA4 without a member of staff on the train you need bigger tunnels for evacuation purposes plus more intervention points. Not cheap. The driver is there for when things go wrong.
Try evacuating a train with no staff that’s 500 metres from the nearest intervention point with no walkway.
Siemens built the factory on the expectation of quite a few years of similar reordering for different tube lines.
They’re not likely to want to develop a variant!
There are too many can’t be done’s in this piece.
Elizabeth Line only has PEDs in tunnels. Why is that different for other lines?
Where PEDs are used on surface platforms they are low level to deter accidents with strollers or texters. A determined jumper will climb over so they do not prevent access to the track.
Curved platform overlap with PEDs needs a setback from the edge for the loading gauge. To mind the gap between the carriage and the PED when opened will require a fold out fill section.
If we ever have PEDs on surface platforms where future services use a mixed fleet they will identify themselves on approach and the concertina gate system will open the relevant gates to the appropriate extent.
The directive for future tube train orders was that they should be capable of future unspecified automation, might that just be a cupboard shelf for the ‘future control computer’.
Brilliant Article, which I’ve linked to from my site.
One further problem with PEDs is presumably that they constrain train variety over time as well as at a point in time. It’s just about possible to imagine installation taking place during non-operational hours (and longer possessions) of an otherwise live service. But once installed, no future change to the pattern of doors could ever be contemplated, because removal and reinstallation could never be done without suspending service for the duration of the work.
Maybe that would never be a problem if all door positions had already reached a state of perfection – but if PEDs were universal across the underground now, it would not be possible, for example, even to consider rrsligning the Western end points of the District and the Piccadilly without enormous disruption.
“Two stations with a single tunnel” seems a strange way of describing the Drain to me, surely there is a single tunnel in each direction?
Either way, great article as always!
Peripherally relevant, perhaps, is something from “Ian Visits” ?
Quote:
TfL is the only major public transport operator not to receive a central government grant, and it also operates the only part of the UK’s strategic road network that receives no routine funding from the Government. That particular issue lead to a heated public fight with a threat to create a new charge for people living outside London to drive into the city to help cover the costs of road maintenance.
The whole article is Here
The Glasgow Subway is to move to Unattended Train Operation (GoA4), notwithstanding the tiny dimensions of the tunnels. Details at http://www.spt.co.uk/subway/modernisation/. This is possible because the system is very simple, the stations are close together and staffed, and the capacity of each train is far smaller than in London. Installation of PEDs cannot start until all of the old trains are out of service, so the new ones will operate initially with a driver.
How does Lyon Line D manage to get away with unattended operation and no PEDs, with only a light-beam detector for people or other obstructions on the track? Fewer passengers or later regulation?
Sorry, I meant “laxer”.
Grade of Automation (GoA) – Train operation – Operation in event of disruption – Example
GoA 0 Driver without ATP – Driver – Driver – On-street trams
GoA 1 Driver with ATP – Driver – Driver – Tyne and Wear Metro
GoA 2 ATP and ATO with driver – Automatic Driver – Paris Métro Line 3
GoA 3 DTO Automatic – Automatic – Train attendant – Docklands Light Railway
GoA 4 UTO Automatic – Automatic – Automatic – Dubai Metro
where
ATP – automatic train protection
ATO – automatic train operation
DTO – driverless train operation
UTO – unattended train operation
See also this Wikipedia entry for more examples.
@PHIL E, 2 June 2021 at 16:27
How does Lyon Line D manage to get away with unattended operation and no PEDs, with only a light-beam detector for people or other obstructions on the track? Fewer passengers or later regulation?
ISTR Copenhagen’s automated modern metro was built without PEDs, and with a sensor system to detect incursions at the platform edge and react accordingly. Too many false alarms from blown debris and people near the edge resulted in the later retrofitting of PEDs at all stations.
@LONDONER IN SCOTLAND, 2 June 2021 at 09:37
The Glasgow Subway is to move to Unattended Train Operation (GoA4), notwithstanding the tiny dimensions of the tunnels. Details at http://www.spt.co.uk/subway/modernisation/. This is possible because the system is very simple, the stations are close together and staffed, and the capacity of each train is far smaller than in London. Installation of PEDs cannot start until all of the old trains are out of service, so the new ones will operate initially with a driver.
With no central conductor rail in the ‘four foot’ (literally only 4ft in Glasgow!), a smooth unobstructed evacuation walkway might also be possible for use with the new units’ cab end fold-down ramps.
LBM
Your little table is a useful supplement to the previous distinctions.
But, what “most people” understand by a “Driverless Train” is the last – UTO /GoA 4.
Which is by far the most difficult & expensive to install & operate.
The question to ask of the politicised proponents of the last is, perhaps:
“It’s 7/7/2005, the Picc-line is UTO & a bomb has just gone off between KGX & Russel Sq. There is no member of TfL staff on board. Now what?”
The whole point of a “driver” or “train attendant” is the last safety fall-back, isn’t it?
Re STUART SHURLOCK @ 1 June 2021 at 17:49
Doing the business case will show you can get the majority of the benefit with resignalling to GOA2 for less than half the cost, the real gold icing can then easily be lost. there need to be a larger line Nth degree of detail with optimal timing comparison to put the nail and screws in the coffin for GOA3/4. TfL pension changes could also undermine the driver cost savings.
No new trains needed, the existing stock was designed for ATO operation. Just four platforms worth of PEDs and resignalling – it is the easiest and cheapest (a bit of a rebuild at Waterloo would also be good).
W&C is there because it is the easiest, cheapest and
bestleast worst business case.Re JUDEP @ 1 June 2021 at 17:58
The W&C is cheaper to “Driverless” by one to (mostly) two orders of magnitude than the other lines and by far the easiest.
It is only me who has noticed that the existing DLR trains will fit on the Waterloo and City line? The W&C was built for main-line size trains and the DLR stock will fit in the here nicely (I checked at it’s true).
The main expense would be to build a (non-service) link link from the W&C to the existing DLR loop at bank so the trains could use the main DLR depot at Beckton. Save having the crane in the trains every 10 years.
But the main question would be would you reverse the trains at Waterloo in the depot or just step-back the service at both ends? Given the usual flow directions and how frequently a service could run with DLR trains, I would think that some first train from indicators at Waterloo would work nicely.
NGH – Fitting PEDs on the W&C to be compatible with the 1992 tube stock, means that they will be incompatible with the version of the Siemens Piccadilly line train which TfL has options to buy. Should those options lapse, the next opportunity will be to tack new W&C trains onto the next Jubilee and/or Northern line order and they are unlikely to be compatible with PEDs set up for the 1992 tube stock.
TfL already has to work out how to deliver the benefits of the Piccadilly line style train (all double doors, walk though, air conditioning) for the Jubilee line with its PEDs. Northern line will almost certainly adopt the Piccadilly line style. I suspect that should a W&C trial go ahead, TfL will have to bite the bullet and alter the W&C PEDs when the new trains arrive.
Brian Butterworth. I fear you have been misled about the size of the W&C tunnels. In its approximately 120 year history it has only had three fleets and all have been tube gauge, and if the tunnels had been big enough there is no reason why the trains should have been so small!
Re BRIAN BUTTERWORTH @ 3 June 2021 at 18:15
W&C tunnels = 3.56m diameter
DLR stock needs at least 4.6m provided the curvature isn’t too large
I know that readers of this site have a more nuanced understanding of how the DLR operates, but if you asked the non specialist reader, most would describe the DLR as already driverless. Which is ironic because for the past year (due to Covid protocols) the DLR trains have – in effect – been fitted with sealed off driver’s cab at each end and the “train captain” now always sits in what would be considered the driving seat. Train captains have not roamed the train throughout Covid operations, they are performing door close duties from the driving position. So the existing “driverless” trains are no longer driverless….
The creation of a “sterile” area at each end for the train captain has blocked off 24 seats (a three car unit has 210 seats) and blocked two door vestibule areas (the first and last sets of doors no longer open at any station), causing a modest reduction in capacity.
Brian Butterworth, ngh
Not only won’t the DLR trains fit in the Waterloo & City, I have been told that you can’t run W & C trains on the DLR due to their inability to take the tight curves. A fairly useless fact but I thought I would add it to the mix.
@PEDANTIC OF PURLEY
I think I might have conflated the “The line consists of twin tubes, 3.70 m in diameter” with the height of a DLR train height 3.49 m. I’m not sure I was suggesting that the existing Central Line trains should ever be taken onto the DLR.
I .. suppose .. that it might be possible to use a small fleet of slightly modified DLR trains within the W&C line to leverage their ability to run their GoA 3 system down there. The DLR trains already use third rail, just in a different place – and this has already been moved in 1940 and 1993!
It all seems much more do-able that starting from scratch with trains that haven’t yet been constructed. Also there are no PEDs on the DLR at Bank, which must be a useful precedent.
Notwithstanding evolving technology the issues have not changed much for many years. LR readers may enjoy the late Mike Horne’s article on this topic which appeared in Modern Railways in September 2012 which can be read on line here:
http://www.metadyne.co.uk/pdf_files/mr_sep12_p62_65_driverless%20trains.pdf
As someone over 100 miles from London but whose daughter having qualified as a commercial pilot was flying fare-paying passengers for a salary of less that 20k the issue of the cost of drivers is missing from the article and comments. The unspoken reason for driverless trains is the impression – true or false – that without an expensive piece of ‘liveware’ at the front then the economics would be different.
Maybe someone with more knowledge than me could break down the costs of TFL : what are the relative costs of drivers/platform staff/electricity/maintenance/etc and put this in perspective.
@ J Elson
Although no disrespect was intended I’m not sure that the comparison with coach driving with regard to the supposedly one dimensional nature of train driving is particularly useful. For sure, the basic stop and go skills for train handling in dry weather are easier to learn than the basics of driving a car with a manual gearbox. If trains were driven by sight whereby we see the lights change ahead of us (signals in our case) and have time to stop then the comparison might be a fair one, but that’s not how it is. A coach driver (as car drivers do) must adjust speed and control of the vehicle to stop within the distance they can see to be clear, in built up areas we know this means taking account of unexpected events that can happen. There is unquestionably skill involved to do this professionally over many hours.
Train driving does not employ the same approach, but it’s far from one dimensional. We use embedded long term memory for braking zones appropriate to prevailing track conditions and signal aspects. Shorter term memory is employed to keep in mind what has just occured, for example if we just passed a single yellow, even though the aws horn and the sunflower indications will be exactly the same for a single yellow or indeed a red signal. The best way I can describe it is this discrepancy between driving by sight and driving by memory, even though that is a bit simplistic.
Let me take you on a short journey encountering events that are not uncommon. You will realise it is a multidimensional one. It is twilight on a rainy day in metroland. You’ve just received an aws indication having transitioned from 4 aspect signalling to 3. You were on a been previously but this time rather than a double yellow you’ve just passed a single yellow. That’s ok though, you know you are bringing your speed down for the junction just before the station which has an graffitied over speed board, but you know the speed reduces to 20 and as the conditions are a bit slippy you get the brake in early. You don’t have to worry about tpws loops in the station as there is no starting signal there, instead you are more wary of an overrun so you test the brakes early in step 2. The wheel slide is there but it is manageable. As you pull into the station people are all huddled at the shelter end with their umbrella’s up. The glare of the station lighting reflects off the puddles and your eyes are darting looking at how close the umbrella’s are to the platform edge and finding your stop board as your usual reference points are obscured. You find it and with a slightly deeper breath you bring the train to a stand. Just before you stop an alarm sounds and a light flashes on your dashboard. You don’t release the doors yet as you want to know what it is. There’s always a delay before the darned fault message comes up on screen. After a few more seconds it does. You are aware of frustrated passengers tapping door buttons. It’s OK it was a loss of line (traction current) from just having gone over the section gap near the junction – it does that sometimes. You release the doors. There’s no point closing them again until your line light is back and you’re beginning to wonder if you might have to call the signaller as perhaps there is a power outage? Great your line light is back, the glare in the puddles and the haze on the cameras makes it really hard to see that nothing is obstructing the doors. Carefully reviewing all cameras you decide it is safe to close the doors. You check all cameras again now you’ve got interlock, it’s been quite heavy going on the eyes but you are relieved you’ve not had to deal with a delay from the loss of line. You remember the wheel slip on approach so take up power slowly, notch two will do until we’ve got good traction, I’ll then open up a bit and see how we go under 3, applying traction sand if required. Not too bad… we round the curve and suddenly the brakes come on, then the horror dawns, the red signal looms into view. Fortunately not a spad – the train stopped but it is an operational incident on your record. The change of 4 to 3 aspect signalling, the extra considerations on your station approach and above all that bloomin’ fault alarm meant I didn’t apply the drivers reminder appliance before I released the doors. So with all the concentration I subsequently invested I completely forgot I had been on a single yellow and that I had started against a red signal around the curve.
This didn’t actually happen to me, but this scenario is not uncommon. I wouldn’t describe any of the experience as one dimensional.
Just one other comment regarding this aside from the main topic. The recent government bailout of TfL made specific mention of the need for mayor Khan to review “the generous TfL pension arrangements”. There you have it. The public seem quite pliable now when it comes to withdrawing other people’s hard fought benefits, be it it in wages, pensions or overall working conditions. This driverless stuff is a smokescreen for where the real attack is coming.
@Latecomer your comment is quite interesting, although I have some comments on it.
1. Road drivers also have to deal with some of the things you mention, e.g. adjusting breaking in poor weather, struggling to see the road against lowsunlight reflecting in puddles etc.
2. Some of the things you mention are exactly where automation excels – i.e. an automated system doesn’t need to struggle with that low sunlight reflection, since it “sees” by other means, also rembering the status of previous signals etc. is not likely to be an issue for even the most rudimentary automation.
That all having been said, these are not the areas which, imo, train drivers earn their money (and the same could be said for pilots too).
In fact it’s those rare moments when something goes wrong when you really need a human there to handle the situation, whether by taking manual control or evacuating in a safe and controlled manner.
In fact I would go so far as to say that longer trains could probably use more staff, not less, for these situations.
With regards to the “Turnham Green” problem:
If the automation is only for frequency increase purposes – since it is only outer stations that have this mixed-use problem, could a hybrid approach – with automation only in the core – not resolve this?
The lower-frequency outer stations could still be driven as now, or with a lower automation level than the core without the need for PEDs.
Indeed – isn’t this exactly what the Elizabeth line will do?
Even the idea that the W&C would be “the easy one” to convert to fully automated doesn’t ring true to me. Although it is indeed a short railway those tunnels are very old, they’re tight and curvy and space below both Waterloo and Bank is very restricted indeed — at Bank there are cellars and undercrofts and utilities going back centuries and which were an issue even in the 1890s when the line was being built. There’s nowhere to go in either direction at Waterloo because of the space needed for Waterloo depot and because the structure is holding Waterloo station up. PEDs would make the platforms a lot more shallow.
And of course, while the Drain is the least-used line on the network that doesn’t mean it enjoys Hainault loop-level pastoral bliss. When it’s used, it’s *really* used, commuters stacked back up the ramp at Waterloo waiting to even get onto the platform. If they were really serious about full ATO, they’d be looking to run a pilot project in a quieter part of the network first to get the technology working — such as the aforementioned Hainult-Woodford loop, as was used for the first automation experiments in the 60s. Above ground, quiet, easy to work with a shuttle service. But then you have to deal with the fact that above ground has its own set of problems — how happy will the comfortable burghers of Roding Valley be to see their pretty GER-era stations defaced with such modern-day abominations as PEDs?
And finally finally, as I understand it the Waterloo and City is the only place where 1992TS drivers (who work both the Central and W&C) still routinely drive manually — so alternative arrangements would need to be found to keep Central line drivers up to date with enough hours of driving in service without ATO. Not sure whether that is actually a problem, but I’d assume that drivers have to keep their licences up to date.
@Mike Knell
Surely a small portion of the PEDs could be built at the less busy end of the W&C platforms, for testing to be performed on weekends when the line is not in public use?
After reading one of the comments regarding what the situation would be in a “7/7/2005” scenario, I thought I would give my personal view. I was on the Piccadilly train that was bombed. I was fortunate to be in one of the carriages further back from the explosion and immediately afterwards we were stuck in a dark, soot filled carriage with no help from anyone and no information. A long time later, staff who had walked along the track from King’s Cross were the ones who finally helped and evacuated our particular carriage and we walked along the track back to King’s Cross. So from this particular perspective, I believe our carriage experienced the same result as if the train was unstaffed. (I clearly understand that in these circumstances the driver was as much a victim as everyone else and in no position to provide us with help.)
Now this may surprise people, but I feel that it is impossible to provide for all possible contingencies, whether trains have staff on them or not. I favour a pragmatic approach to “driverless” trains and automation. Indeed, I am perfectly happy to travel on an unattended train. I think greater automation, if done in the right way, would be more efficient and safer – humans are more prone to make mistakes! As always, it’s the financial cost-benefit and safety that’s important. From a customer safety / security perspective, I would favour staff being at the stations and / or on the platform (or possibly with the passengers on the train) rather than being in a closed-off cab on the train.
It may be difficult to get unattended operation on legacy lines such as Piccadilly line for reasons covered in the article, but I would imagine that the Elizabeth Line could be unattended between Paddington and Abbey Wood, if that was something that TFL wanted to do.
LBM
Hate to tell you this, but in “Normal” times, the Drain was/is open 7 days a week – yes, even on Sundays. Admittedly, it closed early.
@Greg T
I realise that, but but I it’s main function is to transport weekday commuters – Saturday and even more so Sunday ridership is much lower. Closing the line on Sundays or both weekend days will hardly cause hardship.
MV…… You make some very valuable points. I believe that it will be reliability that determines whether or not the attendant can be removed from the train. The utter reliability that ensures that trains always get to the next station. It’s also important that they get away again as the next train will be on its way and will get stuck in the tunnel if the first train doesn’t leave. Assuming the equipment is reliable, the main issue will be people interfering with or getting caught in the doors, or, somehow falling between train and platform (which still happens occasionally on the PED equipped Jubilee line).
The other thing that causes trains to stop between stations is if they “get lost” because wheel slip/slide has caused the odometers to get out of sync – an issue in the open with current ATO systems. This would be resolved by some sort of wheel independent odometry or an unpowered/unbraked axle or two (as on Crossrail).
Finally, staff needs to be around to speak to (remotely) and then walk to stalled trains. then it has to be ensured that trains won’t move whilst this is going on.
In MV’s case, I guess it became abundantly clear that something really nasty had happened, which probably leads to different behaviour than if a train just stops and doesn’t move for no apparent reason.
@DJL
Yes, I agree that road drivers also experience challenges associated with weather, which is why I have no interest specifically on whether coach driving is more or less challenging than train driving (acknowledging as I did that the former is a skilled profession), I was really just wishing to address the ‘one dimensial’ charge made by an earlier contributor. I do think the challenges of weather are quite different in the two roles and certainly the platform/train interface issues are a real challenge at times. I could go into very lengthy explanations regarding what I see as the unique challenges of train driving, but they are rarely fully appreciated or understood until day in, day out experience of the role has been gained.
Regarding your other points I was aware as I was writing my reply that I might have been writing my own obituary! Technology has certainly made the role safer and even now many ‘old school’ drivers assert that modern traction is not ‘proper train driving’. As the article suggests, there’s an almost imperceptible gradation of automation already in existence. In the main I welcome much of it. I dislike the crude fast acceleration and heavy braking I experience as a passenger on the Jubilee Line, stopping abruptly in tunnels only to accelerate again at speed to be brought to a stand again a moment later. Perhaps things have moved on now, but to me it often feels crude and far removed from the eco driving I have been schooled in when on restrictive aspects. I’m also not convinced about artificial intelligence being good enough to deal with all the variables I encounter at stations, but I know the argument is that these duties are more akin to a guard role than driving the train. Personally as a passenger I’m more comfortable knowing that a driver is up front, ‘switched on’ to ever changing events and able to communicate with the signaller over a multitude of events, some of which may appear mundane but could avoid disaster. The feel of a slightly rough ride, water eroding an embankment, a child retrieving a ball high up a slope but potentially able to slip down into the four foot, using my experience to inspect the line when required – and of course the preparedness for evacuation or keeping passengers sufficiently well briefed so as to avoid uncontrolled evacuations. Some of these I feel better placed to do because I’ve been driving the train rather than just sitting there, but I’ve heard the counter arguments ad nauseum so I won’t involve myself too deeply into whether my role should be driver, train captain, guard, person in charge or remote control operator. There is usually an attempt to oversimplify what we do and to stress the ‘button pushing’ supposedly one dimensional aspect of train driving as a precursor to saying our wages are too high and that it can be done better by a computer, or by a computer and someone on far less pay. I’m not convinced of the economic argument, nor of the case that greater automation means that the driver role should be redundant
DJL – 13:29h, 07/06/21.
Latecomer as always sums it up well. I’d say this is exactly where you earn your money, just like the emergency situation you allude to.
Now I’d agree that much of this could be automated. But I’d hazard a guess that balancing the different stimuli would be difficult unless you had PEDs. And even then I’m not convinced that would end up,as the ‘be all’.
Drivers are aware of the changes that all the variables can adjust what appears standard but can change on an hour by hour or day by day basis – a recent shower, a packed platform due to a cancelled train, maybe a local sporting event or the time of day changes the mood and movement of the passengers. Would an automated system adjust it’s approach? Yes if it had AI but I’d hazard no otherwise….
‘Driving’ a train is easy, being a train driver far less so.
Re: John Thorn – 06/06/21
Not wanting to go down the thorny rabbit hole of pilot pay versus train driver pay, one interesting point to note is that there are at least three recent recruits at my TOC who were previously pilots. Not surprisingly they tend to turn out to be very good at the job of train driving – strong non-technical skills, situational awareness etc, the ability to monitor the train as and when required and to up change their focus as the situation dictates…
I’ve asked why they left the world of flying to ‘button push’ as a train driver and the arguments are always the same, circling around pay, conditions, support within in the industry. None as yet say they regret the move though only time will tell.
I’m sure your daughter chose the world of flying because that is what she wanted to do and that is where her interests lie, it doesn’t feel like the sort of job one falls in to. I can imagine in the current economic climate in the travel industry it is very difficult for pilots at the moment which must be very hard for people having forked out enormous amounts of their own money just to be left at the door by an airline. There was an article on the radio about it only yesterday where a former pilot was talking about a charity set up to try and support pilots through this difficult time. Ironically, when asked what he now did for a living at the end of the interview his response was “I’m now a train driver…”
My final point, really already made by Latecomer, is that there is an awful lot of misunderstanding about the train driving role and a desire to win political arguments by oversimplifying this role. If you want to learn more about the issues and challenges that drivers face, have a look at some of the wider research and work undertaken by industry bodies such as the RSSB. Not surprisingly though, we as an industry continue to learn much from many of the good practices within areas such as aviation.
@ Brian butterworth
“But the main question would be would you reverse the trains at Waterloo in the depot or just step-back the service at both ends? Given the usual flow directions and how frequently a service could run with DLR trains, I would think that some first train from indicators at Waterloo would work nicely.”
Not possible to reverse in Waterloo station, as there is no crossover at the Bank end of the station. Stepping back does happen at busy times, but it is done in the reversing siding in the depot.
@Timbeau
Would it not be possible to add a crossover? In this hypothetical scenario, adding an extra crossover would be the easy part…
It is worth noting PEDs are not a perfect solution. There are a number of risks that are reduced but not removed as well as some modification to existing risks.
One risk is the gap between the PEDs and the train when closed. It was demonstrated that a thin adult could get between the PEDS and the train doors on the Jubilee line so children probably can as well. This has happened on one of the Metros in the far East where there was a much larger gap – a customer decided that he would stand on the train side of the PED screen. He received the Darwin Award when the train moved off. According to the operators the train driver was supposed to check the gap after the doors closed but it is not clear how.
Another hazard particularly with tube stock and straight PEDs is that passengers could climb either fully or partially onto the roof of the train.
The double door arrangement introduces the same problems of strong items such as belts, straps, dog and child leads ( I thought we had got rid of child leads after one was killed in a lift ?) If the lead / strap is unable to pull through the doors the objects on both ends will be dragged into the doors till something breaks – it may be the strap or the person.
This is also related to the infamous problem on tube trains of last borders adopting the ‘heads down bums out’ position as they try to squeeze on and avoid the closing tube train doors. This is one of the main reasons for the problems with coats being caught in Victoria Line train doors in the winter.