ATO, a Go-go: Signalling the SSR

On Sunday 17th March 2019 Automatic Train Operation (ATO) was finally, and successfully, introduced on the Sub-Surface Railway (SSR). Next week, or maybe the week after, we’ll put the significance of this in context and look at future planned developments. Meanwhile, if an illustrated article about signals wrapped in black plastic would interest you, read on…

Nice but dull

One of the downsides of modern signalling is that it has none of the visual imagery of the signal gantries of old. The sight of a multitude of signal boxes, each with their own architectural character, has long gone. In most cases this has been replaced by visual displays and a modern signalling centre often looks little different to any other modern office.

Automatic Train Operation usually results in removal of trackside signals though one does not necessarily imply the other. You can replace trackside signals with in-cab signalling and that does not necessarily mean automatic train operation. Conversely, ATO does not necessarily mean the removal of signals though generally, it does.

Central line is the exception

On London Underground, the exception to the general rule is the Central line. Although ATO, this has a form of lineside signalling to inform the driver of the status of the line ahead. However, he/she is not required to ‘observe’ signals in the traditional way.

So it is then, that on the London Underground, Central line excepted, the primary visual clue that a line is automatically operated is the apparent absence of signals.

One small section for auto

ATO is now live on the Hammersmith & City (H&C) and Circle lines between Hammersmith and Latimer Road. That is a mere five stations and ten platforms where train operation is fully automatic (three at Hammersmith, two each at Goldhawk Road, Shepherd’s Bush Market and Wood Lane and one at Latimer Road).

Let us take a look at what has been implemented so far and how it looked on the first day of passenger operation.

Hammersmith

Exterior of Hammersmith (Hammersmith & City and Circle lines)

We start our journey at Hammersmith (H&C and Circle lines). This is a delightful little three track terminus. The station was opened out a few years ago by the necessary demolition of the ticket office to enable platforms 1 and 2 to be extended. This, of course, necessitated the construction of a new ticket office which was then closed a few years later.

Here one quickly sees a limitation of the new system, as currently installed. The platform-based passenger information displays helpfully tell you which platform the next train to leave will depart from, but not when.

This, coupled with the train doors closing automatically if left open for 45 seconds without being used, means that people are not passing along the platform to spread the loading on the train.

The rather unusual location of the buffer stops at platform 3

Catering for longer trains also necessitated extending platform 3 into one of the existing buildings, giving the platform a rather unusual feel about it at the buffer end.

Also at Hammersmith and visible before boarding is an often-overlooked feature of implementation of ATO. Existing but redundant notices, as well as signals, have to be ‘bagged’. This generally means liberal use of black plastic to cover them up.

Whilst still at what is traditionally known as the buffer stop, note that the ‘C’ marker to tell drivers where to stop when driving six-car ‘C’ stock is still present, even though the stock was scrapped around five years ago. Note also that the fixed train stop in advance of the train arrestor (buffer) is now redundant. The tripcocks on the trains will be removed once all the relevant lines are fully automated. For the present the trainstops on automated sections will be ‘pegged down’. These will eventually be removed along with the now-bagged signals.

A close up picture of this signal can be found here

Hammersmith station has a nearby former depot visible from the platforms. It is a former depot because trains are now no longer maintained there. Its official designation is now Hammersmith sidings.

Because of the sidings, Hammersmith probably illustrates better than anywhere else the sheer scale of ‘bagging’ required. The signal spacing on Underground lines with manually driven trains are usually very short by railway standards, so a lot of black plastic is required. The expectation is that the signals along with the redundant wiring,  pegged down trainstops and redundant notices will be removed once there is no possibility of going back to the old system. This is because it is good signalling practice to remove redundant kit. The rail crash at Clapham Junction in 1988 provided significant evidence for this, as it was caused by contact of a live signal wire with a newly-redundant one.

Stray plastic on the track at Hammersmith. This should not have happened and the concern is that something is visible that should not be.

Observing a departing train will show the implementation of a newly-activated feature on them. The yellow outside lights are lit up when the associated door is open. Above that is white light which shows that the signalling system tells the train it is ‘ready to depart’. The period between ‘ready to depart’ commencing and the doors closing is very short. London Underground, being London Underground, has actually thoroughly investigated this timing and decided what the ideal length of time is.

Goldhawk Road

The first station north of Hammersmith is Goldhawk Road. The stations on this branch are quite closely spaced but, exceptionally, from Goldhawk Road platforms you can actually see trains depart from the adjacent station (Hammersmith). It is the least used station on the Hammersmith & City line. It is also the first station we encounter which is in the typical Hammersmith branch style – rather basic but functional and painted in dark and light brown as part of its heritage (it was originally a GWR station).

Goldhawk Road. The picture doesn’t really do the station justice. Note the white light above the yellow light on the side of the train

Here the rather basic functionality of the customer information system (platform indicators) is replicated – at least in the northbound (officially eastbound) direction. The destination of the first train is shown and when it approaches you are told that the next train is approaching – and that is it. On the opposite platform the information you would expect is displayed with the first, second and third trains showing, along with their destination (Hammersmith) and how many minutes before their arrival.

Shepherd’s Bush Market

Shepherd’s Bush Market is a station very similar to Goldhawk Road except that it has passengers. The number of passengers may be surprisingly few but this can be explained by the fact that the line was advertised in advance as closed for engineering work the entire weekend.

In fact, there was no engineering work as such – just implementation of the new signalling system and trains were running all weekend. It is just that passengers weren’t allowed to use them between Paddington and Latimer Road until Sunday afternoon. Presumably, it was thought better to close the section from Paddington to Hammersmith rather than allow passengers as far as Ladbroke Grove or Latimer Road and leave those who hadn’t spotted the shortened service stranded there.

At Shepherd’s Bush Market one of the signal plates appears to be left unbagged but this is in fact a structure identification plate which goes to show how methodical one has to be when ‘bagging’.

Wood Lane

Wood Lane is a very modern station, completely out of character of the rest of the line, which was opened in 2008 to cater for the adjacent new shopping centre.

The southbound signal at this station must have had a sighting issue as there is a permanent blind installed above the now-redundant signal – one of the advantages of getting rid of signals is that signal-sighting issues just go away.

Latimer Road

Latimer Road station has a famously inappropriate name nowadays as it is around 500 metres from the current Latimer Road. By Hammersmith & City line standards it is a quiet station. On the first day of public ATO operation the number of rail staff generally exceeded the number of passengers. This was because every driver on this weekend was supervised between Latimer Road and Hammersmith. This meant driver instructors would leave the cab of a northbound train and cross over to the other platform to wait at the far end for the next train they would supervise back to Hammersmith.

It was reminiscent of Thameslink last May when a lot of drivers did not have route knowledge to drive through the central section. They had to be accompanied by one of a roving group of drivers with the appropriate route knowledge.

The other relevant thing about Latimer Road was that as it is the end of ATO there has to be a sign to remind the driver of this. So northbound there is a signal at the end of the platform – the first one encountered from Hammersmith – complete with a sign to indicate to the driver that he is leaving an ATO area. The sign is expected to be short-lived, with removal expected within four months.

A curiosity is the repeater signal, now bagged of course, on the southbound platform. This would have originally been installed primarily for the benefit of the guard but, of course, there hasn’t been a guard for years.

Often these were left in place as they were still of benefit to the driver and it was cheaper to maintain them than remove them.

The immediate future

ATO on the SSR seems to have passed its first tests in public service. Of course, Sunday is generally a quieter day passenger-wise and with the line advertised as closed, the first-run was especially quiet. But a quirk of the H&C and Circle lines is that the service frequency on a Sunday afternoon is the same as during Monday to Friday peak hours. Consequently, it served as a solid test for the peak.

It has indeed turned out that there were few problems during the week following and those that have manifested appear to have mainly been teething troubles. So the implementation of this first small section appears to have been a success. It will be interesting to see how long the signals and other redundant paraphernalia remain in place.

The biggest problem on the opening Sunday afternoon appeared to be the slightly erratic service characterised mostly by the bunching of southbound trains, but also by the occasional apparent cancellation leading to large gaps of up to six minutes and maybe more. This was probably down to a lack of drivers (including driver instructors) during this period where there were two people in the cab between Latimer Road and Hammersmith.

This is a ‘look on the ground as it is’ report of the start of ATO on the SSR. Next we will look at why it took so long to get here and what the future plans are.

Meanwhile, if one article on the opening of this section isn’t enough for you, there were excellent reports by Diamond Geezer on the opening day and by Mike Horne later on a visit during the first week. There is also a related article on Hammersmith Signal Cabin by MoreToJack.

38 comments

  1. Editors note: apologies if the captions look a bit strange on this article – there’s been a major upgrade to WordPress (the CMS which powers the site) and we’re still getting to grips with how it works!

  2. The article writes “(Goldhawk Road) was originally a GWR station”.

    In fact, it’s the product of splitting Shepherd’s Bush (now Market) station, well into the late period of the Met’s ownership. In fact, it’s less than two decades before LPTB.

    And today is incidentally the 105th anniversary of the station.

  3. I for one (and probably only one) can’t get enough of ATO signalling!

    Does this section having ATO now no longer mean that the trains have to blow a whilst approaching Shepherd’s Bush?

  4. Good article.

    Does anyone know if LUL has a policy regarding the number of years (or even decades)redundant signalling and power cables and equipment are left in situ?

  5. The sign labelled “SG51” in the photo above is a structure identification plate, not a signal plate.

    [Thank you for that. I did wonder if there was a good reason which is why I was careful to state “appeared to …”. Article Updated. PoP]

  6. Signalling, the SSLs, and the date – I was expecting a joke article saying how it’s ahead of schedule and all going swimmingly, rather than a serious article . 😉

  7. “Presumably, it was thought better to close the section from Paddington to Hammersmith rather than allow passengers as far as Ladbroke Grove or Latimer Road and leave those who hadn’t spotted the shortened service stranded there.”

    More likely: if there was a problem with a train switching to CBTC at Latimer Road, the trains inevitably stranded in a queue behind it don’t have any headaches with duty of care, nor self-evacuation.

  8. Just a little correction regarding Clapham Junction. That accident was caused primarily by lax installation practices during ‘stagework’ wiring in an existing relay room as it was being slowly migrated over a number of weekends from the old colour light system to new colour light equipment. The advantage with this new type of CBTC compared to that scenario, where old and new track circuits for example share the same electrical rail connections is that the new system almost entirely separate from the preceding, employing different train detection techniques for example, so there is almost no commonality between the systems except for connections to point machines. Indeed the CBTC, as far as I know, can be powered up working in shadow mode with everything working (apart from the points obviously) for a period before commissioning for it to settle in and shake out any rogue components, then very large areas can be switched over to the new system at once with comparatively short possessions. With the old signalling now surplus to requirements, there’s very little risk in it remaining in situ and it’s certain the fuses for signal lamps etc will have been removed anyway. It will all be be removed eventually of course, but at this first stage I suspect they may retain it for a while longer as a backup just in case something totally unforeseen happens with the new signalling. In the highly unlikely event of having to change back, the independence of the two systems would allow a fairly speedy changeover again.

  9. Second picture in the Wood Lane section (the one with the blind in it, seems to have two many ‘signals’ in the caption under the picture!

    Apart from that excelent article as usual.

  10. Ryan,

    Yes, another good reason to chuck passengers off at Paddington

    Mark Townend,

    Point taken but the cable at Clapham Junction was redundant and not properly terminated. Basically, if a cable is not achieving a purpose it should be removed eventually. You never know what might come into contact with it and the consequences of that.

    Apart from anything else, if it is left unidentified it could cause problems at a future date as work would have to stop until it was identified.

    James,

    Thanks for pointing it out. Now corrected.

  11. You may be able to see the platform at Hammersmith from Goldhawk Road, but this is because the line is straight rather than them being especially close; I believe the gap between them is actually the longest gap between stations on the branch!

  12. Paul,

    When I read this I was really surprised but the Working Time Table (on page 3) shows this is indeed the case. Article amended to reflect this.

    Here is the extracted table with distances in kilometres. Conventionally these are taken as platform centre to platform centre to avoid distortions at the end of the line.

    The fairly recent addition of Wood Lane has plugged the previous largest gap. The largest gap is now between Royal Oak and Westbourne Park with Hammersmith and Goldhawk Road second.

    In general, these are surprisingly consistently close spacings for zone 2 stations.

    If you bear in mind that S7 trains are more than 117m long, if you had double-ending of stations on the branch you would practically have bus stop distances between entrances. Certainly tram stop distances.

  13. supervised between Latimer Road and Hammersmith … use them between Paddington and Latimer Road … better to close the section from Paddington to Hammersmith

    Just a minor request, but keeping the “direction of conversation” consistent can make it easier to read articles about stations along a route, particularly when there’s no map or illustration. In this article the main narrative direction is starting from Hammersmith, so these station pairs can be switched around.

  14. People don’t need to “pass along the platform to spread the load along the train” as it is walk-through stock
    People board by the first door and walk through until they find space, meaning there is always room for the “late arrivals”. I have just observed this behaviour at Richmond – people were still walking down the train – and finding seats near the front – until it reached Kew Gardens.

  15. timbeau,

    That is true but it wasn’t what people were doing – admittedly on a lightly loaded train. But, by preference, people tend to prefer to continue along the platform rather than in the train.

    If they knew the train wasn’t leaving for another three minutes they would probably be more inclined to walk along the platform and spread the load more evenly. It would also avoid the scenes of people attempting to run believing that the train might imminently depart.

  16. Nice overview. But aren’t there still bagged up signals on the Jubilee line where it shares with the Met? Clearly removing them isn’t exactly a priority for TfL…

  17. Muzer,

    I always looked out for them on my few trips a year on Chiltern Railways. They do seem to have now gone – unless someone says otherwise.

    It always was part of the upgrade but it is only recently the relevant department has asked for authorisation to spend the final amount in order to remove these. I seem to recall it is a surprisingly expensive task – then again this is the railway so one wouldn’t expect anything else.

  18. @PoP

    It probably does depend on the time of day – and possibly the weather. I used the H&C on Sunday morning and there was not much evidence of people walking down the train (I was in the rear carriage anyway as I was going to Euston Square) then. (As I said, it is a different matter at Richmond in the morning peak). Indeed, I was surprised at how many of my fellow-travellers seemed to be taken by surprise by the need to walk through to the next car at Baker Street.

  19. timbeau,

    Baker St, platform 5, last carriage. Catches them out every time. It always seems to be a fresh set of tourists who I presume are travelling to Madame Tussaud’s. It is just as well eastbound trains tend to have to wait there anyway otherwise the effect would be quite significant (and difficult to fix without an awful lot of money – something TfL doesn’t currently have).

  20. @POP, 1 April 2019, 20:44
    Clapham graphically highlighted the particular risks of old wires left unterminated and unprotected in equipment rooms with working circuits nearby. A problem in old relay rooms is that the wiring insulation is often deteriorating so pulling individual redundant wires out of packed raceways risks stripping insulation from adjacent wires, and that could also result in unwanted electrical contact between random circuits with unknown consequences. Often in these circumstances the wires are thus left in situ but should of course be properly cut back as far as possible and the ends insulated. It was always good installation practice to do that, but I don’t think the requirement was formally documented anywhere.

    Like most drawing office juniors, I often volunteered for lucrative overtime at weekends to assist testers in project commissioning activity. Thus in the early 1990s I found myself out on a stage of the Chilterns ‘total route route modernisation’ SSI resignalling one Sunday when the job in hand had gone very well with all work already complete by the early evening. We had been carrying out aspect sequence testing which is one of the final checks before commissioning. Staff are dispatched to various signals to verbally confirm aspects displayed while the tester in charge sets routes in the control centre. With work complete in our designated area, we walked back to our car along the track from Gerards Cross towards Denham and around the curve just by the M25 bridge a colour light signal came into view ahead. It soon dawned on us there was not supposed to be a signal in that area at all in the new system so we investigated. Although it was cut off from all mains power and control circuitry, we found Denham’s old colour light distant still defiantly beaming it’s default yellow aspect out into the evening gloom on local battery power. We reported it in to control and a recovery gang was quickly dispatched to put it out of its misery!

  21. @PoP
    “by preference, people tend to prefer to continue along the platform rather than in the train.”

    Another factor in the difference between Richmond and Hammersmith commuters’ habits in this respect may be the degree of trust they have in the information displayed. There also seems to be no reliable way of distinguishing between the doors closing to keep the heat in, and doors closing because the train is about to depart.

    Several people were caught out this morning when a train displayed as due to leave at 0859 actually left at 0856 – it wouldn’t have been so bad except the display then announced that the next two trains were both cancelled. (And apparently a 33-minute gap only merits “minor delays”)

  22. Pop writes: “by preference, people tend to prefer to continue along the platform rather than in the train”

    I agree. I find it difficult to get down the inside of the train weaving between the grab bars, especially when it is quite full. And it is especially irritating when people walk very slowly (holding up a large queue of people behind them) or else stand and block passage down the train. I would walk down the outside, but I have no idea when the train is about to depart.

  23. Some of the signals on the Jubilee and the Northern line have been bagged for so long I am surprised they haven’t assigned asset numbers for the bags

  24. @DT-R
    The redundant power cables are well into their second decade of disuse.

  25. Regarding the bagged repeater signals, they were retained after the abolition of guards because staff performing train dispatch duties (if the monitors are defective) need to know if the train has a green signal.

    The white light on the side of the train is now provided for the same reason.

  26. Interesting article!

    Side track:
    Might be a good idea to put in a warning that on the first visit to the MoreToJack site it will redirect the browser to some irrelevant advertisment/spam site rather than displaying the actual MoreToJack site.

  27. I too prefer to walk along the platform. This avoids hitting my head on the noose-like handles, being stuck behind someone on their blower yakking on about the price of fish or simply having to vault suitcases and dogs in the gangway.
    A very helpful driver explained the white lights above the amber door lights but they are a poor substitute for a gert big green to amber signal which everyone can understand.
    If TfL want people to board all along the train, then perhaps they should leave the old signals at terminii such as Hammersmith or institute a countdown a la pelican crossing traffic lights.

  28. A small error in the article. The article says that a quirk of the H&C and Circle lines is that their frequency is the same in peak as it is off-peak. I am sorry to inform you that this not the case. A careful study of Working Timetable No.35 on TfL’s website will show you that on the Monday to Fridays timetable there are 2 interpeak stablers if you look at the list of train numbers on page 5, namely Trains 171 and 172. These effectively mean that the Circle and H&C run for a short time in the peak at 8 minute intervals not 10 minutes. If you carefully follow Hammersmith departures in the timetable pages you will see the “push-in’s” in the approx 07.30 – 08.15 time range. I haven’t gone looking for the extra trains in the evening peak, but rest assured they are there.

  29. asl,

    True and I wasn’t aware of this. But this is very minor and doesn’t really negate the point made. You will also see in the working timetable that in the Summary of Train Intervals (page 4) the Circle line is reported as being every 10 minutes all day every day of the week. The Hammersmith and City is almost the same but between 9½ and 11½ minutes.

    Don’t be deceived by thinking that more trains means a more frequent service. There a very slight increase in service from Hammersmith but one of the trains involved sits at Edgware Road for 2 minutes and takes a full 5 minutes longer to get to Barking than a train shortly after 6 a.m. So basically those push-throughs are extra trains to keep the service frequency roughly the same as in the off-peak – which was the point I was making.

  30. So when the upgrade reaches Earl’s Court will we lose the first train to depart signs on the Eastbound platforms ? It’s suprising how many people use those and / or the signals to change trains for a speedier journey. Sometimes drivers are friendly and reveal they won’t be first out but they are in the minority.

  31. Addendum to the comment about “no signals, no problem” just look out for the white lights above the amber ‘doors-open’ ones on the carriages.
    Yeah, but no but.
    It appears that you can’t wholly rely on this. A little esoteric I grant you, but the train I was nonchalantly ambling alongside five mins ago, all the while watching the ambers, did not obey the rules!
    Yes, there were beeps and yes, a door closed. But no, there was no change to white lights and yes, the blummin train went off on its merry way.
    Another helpful employee, upon me asking about this replied “Who told you about the white lights?” and then apologized for not having an answer.
    It is admittedly not much more than a niggle, but can anyone enlighten me please?

  32. The unusual numbering of SMA 0.5 results from this area being a subset of SMA 1, the original planned inaugural area, which will reach Paddington. SMA 0.5 is a small area to allow for driver familiarisation, since inaugural trips are accompanied by an instructor to provide assistance with switch-over into and out of the new cab signalling system. There is a limit to how many instructors can be rostered available thoughout the day, so a 7 minute run makes more efficient use of their time. With the next area, District line west end crews will only experience a 3 minute run from Paddington into Edgware Road, whilst Metropolitan line drivers will have 10 minutes from Finchley Road to Euston Square. East end District line train staff will then have a 9 minute run between Stepney Green and Monument in the third stage.
    As installation has progressed, each area has commenced Shadow Mode Running, which means that it communicates with fitted trains, monitoring their position and the movement of all points. It does not control signals and points, but will sound alarms as necessary to give a trial of the system under daily traffic conditions. From January 2019 this was being done around all of the Circle line.

  33. You mention that platform repeaters were provided for the guards whose role was superseded by the introduction of one person operation. However these repeaters were always also there for use by platform staff whenever present. The white lights on each car replace this latter function.

  34. Peter Young,

    Agreed. But I got the impression that it would be highly unusual for them to installed on a line that was already operated using trains without guards and I don’t know if this ever happened. In most cases the relevant signal was visible from critical points on the platform as required by platform staff. So, it seems to be more a case of: if they were already installed, why remove them?

    Note that white lights for this purpose are nothing new. For example, they are present on the Jubilee line but in that case they are on the platform, not on the train.

  35. @PoP

    Presumably the white lights being on the platform on the Jubilee Line is because the platform doors would obscure the view of train-mounted ones.

  36. UPDATE
    I’m not sure if this has been mentioned or not, but, apparenly, the further migration of the SSR re-signalling/upgrade past Euston Sq as far as the Aldgate triangle, has now been “paused indefinitely” – or so my copy of Branch Line News tells me.

    Incidentally, after searching for a suitable article to post this in, I noted that the headers give the date of an article’s first publication, but NOT the year.
    Perhaps a small upgrade/mdification to include the year as well as the Day/Month might be in order, please?

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