North End
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Post by North End on Apr 9, 2021 12:38:40 GMT
Thanks all for your informative responses and also the continuation of some of the interesting discussion about the Drayton Park - Finsbury Park tunnels - one thing's for sure, I really hear/feel the gust of air whenever I travel past this stretch on the Victoria line, as they serve as natural ventilation... arguably more effective than some of the purpose-built intermediate fan shafts, many of which you don't hear/feel when the train goes past them (maybe because the fans are switched off these days?) I know there were some complaints about the Pulross Road shaft when the fans were upgraded back in '09: brixtonblog.com/2019/12/resident-protest-sees-giant-brixton-fan-switched-off/?cn-reloaded=1In general the answer is very much no. However, there is of course the Netherton Road shaft which is setup as an escape location, and has always been so since day one. There’s a couple of other fan shafts on the Vic Line which I believe are set up for man access, though for security reasons it’s probably best I don’t post which ones. I’ve no idea what they actually contain (the ones concerned happen to be on the only section of Vic Line which I’ve never had the opportunity to explore at track level!), but going by what exists elsewhere I’d suggest it’s probably something like a small metal spiral staircase. The size of the head house will generally be for two reasons - firstly the tunnel fans are quite large, and secondly because the tower needs to be taken up to whatever is the prevailing roof level. Thanks North End. Without meaning to breech security myself, I note on the TfL Property Asset Database Map linked above by Quex, the Somerleyton road shaft in Brixton is labelled as emergency escape, perhaps for safety reasons because it is at the end of the running lines, and potentially for T/Ops to escape from there if they find themselves 'trapped' in the siding in the event a train terminates there? I don't believe there is an equivalent set up on the opposite end of the line at Walthamstow. On the topic of that Property Asset Database Map, unless there is a layer switched off that I am not aware of, it's a shame that many of the other lines aren't as detailed as the Victoria line is. For example the Victoria line sidings are displayed, complete with the emergency escape cross passages at the end of the sidings to connect with the mainline running tunnels. Whereas the Piccadilly line, for instance, lacks any such detail. -- For those interested, there's a useful diagram in the following ICE article entitled 'Squeezing the heat out of London's Tube', which shows where the shafts are and how they work: www.icevirtuallibrary.com/doi/pdf/10.1680/cien.2010.163.3.114?download=trueSomeone with local knowledge would have to confirm, however I don’t believe there’s access at Somerleyton Road. The cross passage from one siding to the other would satisfy any emergency egress requirement. My guess is the shaft probably has a rudimentary ladder. I did walk down the sidings when exploring that part of the Vic Line, however there were trains stabled in there so we didn’t go right to the end. I’ve certainly seen no mention anywhere of any facility for staff to be able to leave there - but having said that there’s plenty of places I am familiar with where it’s possible to do that but which aren’t officially listed as such. Even some of the outwardly obvious ones like disused stations aren’t that well documented - the Met Line ones between Baker Street and Finchley Road are very much on the radar, but somewhere like Bull & Bush isn’t. The main use for these features is for contractors and the like.
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North End
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Post by North End on Apr 8, 2021 21:50:25 GMT
That ties in with what I recall. My memory is slightly vague, but I think the north end of the tunnel ends in a solid wall. Certainly I entered it side-on via a cross-passage from the s/b Victoria Line tunnel. Wish I’d had a bit more time, though I certainly had (made!) time to walk all the way to Drayton Park and back! Bet that was quite an eerie experience, with the noise and air-rush of nearby trains! It was overnight so all quiet. Have been down tunnels when there’s train movements in a nearby tunnel though, indeed very creepy. I seem to remember after the Drayton Park excursion timing it to climb up onto the platform at Highbury with only a couple of minutes to spare before time. Not really a problem, but one has to know the section well to do that, wouldn’t want to be stuck in the middle of a long section like Finsbury Park to Seven Sisters!
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North End
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Post by North End on Apr 8, 2021 21:29:50 GMT
The tunnel mouths were demolished and landscaped. It is, however, possible to walk through the n/b former tunnel from the Finsbury Park end, and emerge at Drayton Park in the vicinity of where the tunnel mouths were. The gate is narrow and at right angles to the tunnels, so I’m not sure what any benefit would be of removing rails this way. Could someone have added 2 + 2 and come up with 5? Yes, and that tunnel is blocked off at the Finsbury Park end just before what is now the crossover from the southbound Vic to the southbound Picc. With my mod hat on, I’ve been instrumental in dragging this thread off topic, so I’ll split it tomorrow.
That ties in with what I recall. My memory is slightly vague, but I think the north end of the tunnel ends in a solid wall. Certainly I entered it side-on via a cross-passage from the s/b Victoria Line tunnel. Wish I’d had a bit more time, though I certainly had (made!) time to walk all the way to Drayton Park and back!
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North End
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Post by North End on Apr 8, 2021 21:27:35 GMT
Looks like the old tunnels to me. All they seem to have done is demolish the portals and then landscape what was left. From the inside, both tunnels now end in a pile of spoil, like quite a few disused mainline tunnels do when one end is buried. As to why this was done, who knows? It could have been to make space for the crossover which was installed at the north end of the platform, but that’s just a guess on my part.
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Post by North End on Apr 8, 2021 20:57:24 GMT
This was at the time of the Victoria line opening, so before they had got around to sealing the tunnels. And there must still have been some access for Metronet to remove redundant rail more recently! Interesting, because my recollection is that access from Finsbury Park (tube platforms) to Drayton Park was cut before the Vic line opened. The only link was to the BR station, which was used for stock transfers to and from Highgate (latterly Neasden). The tunnel mouths were demolished and landscaped. It is, however, possible to walk through the n/b former tunnel from the Finsbury Park end, and emerge at Drayton Park in the vicinity of where the tunnel mouths were. The gate is narrow and at right angles to the tunnels, so I’m not sure what any benefit would be of removing rails this way. Could someone have added 2 + 2 and come up with 5?
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Post by North End on Apr 7, 2021 22:41:56 GMT
"From a civil engineering point or view the most interesting lines are (IMO) the Northern, Jubilee and Victoria. The Vic is a lot more interesting than its simple route on the Tube Map might initially suggest!" (North End) Yes indeed...My understanding is that various sections were built using different tunnelling methods by way of comparison. I have also heard,which may be an urban myth,or a misunderstanding of the above,that the Vic incorporated some earlier,pre-existing tunnels in its construction...no truth in that? Surely? Yes there is some truth in it. Firstly there were two experimental tunnels built from Finsbury Park to Netherton Road, which were essentially trial tunnels for the Victoria Line construction methods. They were specifically built on the proposed Victoria Line alignment. Two of the three working sites were incorporated into the Victoria Line as permanent shafts, as well as the full length of both tunnels. Secondly there was some use of other lines tunnels at both Finsbury Park and Highbury - at Finsbury Park the s/b Victoria Line platform is the former s/b Northern Line, whilst the n/b Victoria Line platform is the former w/b Piccadilly Line. Likewise at Highbury the s/b Victoria Line platform is the former n/b Northern Line. The s/b Victoria Line also uses a long(ish) section of the former s/b Northern Line running tunnel from Finsbury Park towards Drayton Park. The former n/b Northern Line running tunnel remains unused alongside that, cross passages connect with it. From memory the unused Northern Line tunnel still contains track, and is intact all the way to where the Drayton Park tunnel mouth used to be. Not somewhere ever likely to be open for visits I’m afraid, as both ends are trackside. The section of 16-ft diameter Northern Line tunnel used by the Victoria Line south of Finsbury Park can clearly be seen on the Video 125 cab ride. The point where the tunnel transitions back to “new” Victoria Line construction can also be felt as a passenger, as the change of tunnel diameter tends to result in ears popping.
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North End
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Post by North End on Apr 7, 2021 22:30:48 GMT
The Vic has a lot of cross passages. Some of these are intermediate fan shafts, however there’s also plenty of former construction sites where there might be a cross-passage or two complete with the remains of an infilled former construction shaft. Especially south of Victoria there’s quite a few. Thanks North End. For the intermediate fan shafts, do these include emergency escape up to the head-house? I'm always surprised by how big some of the head-house buildings are, particularly the one at the end of the running lines at Somerleyton Road. In general the answer is very much no. However, there is of course the Netherton Road shaft which is setup as an escape location, and has always been so since day one. There’s a couple of other fan shafts on the Vic Line which I believe are set up for man access, though for security reasons it’s probably best I don’t post which ones. I’ve no idea what they actually contain (the ones concerned happen to be on the only section of Vic Line which I’ve never had the opportunity to explore at track level!), but going by what exists elsewhere I’d suggest it’s probably something like a small metal spiral staircase. The size of the head house will generally be for two reasons - firstly the tunnel fans are quite large, and secondly because the tower needs to be taken up to whatever is the prevailing roof level.
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North End
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Post by North End on Apr 6, 2021 22:30:19 GMT
The other day my Victoria line train waited outside the crossover on the southbound, as it quite often does while awaiting platform availability. On this occasion I happened to be standing at the first right-hand set of double doors in the fourth car in direction of travel; when peering through the window, the train on the adjacent northbound illuminated a cross passage. I wondered if this was the Pulross road shaft but I am not sure it is, as I'd have thought the opening for that is the one slightly farther up the line (which I've never stopped by but can be spotted because it contains a switched-on light, though blink and you'll miss it!) Or does the Pulross road shaft have two openings (albeit roughly a train length apart?) If not, what is the purpose of this cross passage? I have tried to see how these appear from a driver eye view in the following video: <<rincew1nd: video removed>>There appears to be crossover/vent openings at: 27:22 (closer to Stockwell) 28:48 29:02 Unfortunately the video doesn't go all the way to Brixton, but my assumption is that 29:02 is the opening I spotted from on board the train from which I could see into the cross passage as the northbound train passed and illuminated it. The Vic has a lot of cross passages. Some of these are intermediate fan shafts, however there’s also plenty of former construction sites where there might be a cross-passage or two complete with the remains of an infilled former construction shaft. Especially south of Victoria there’s quite a few. From a civil engineering point or view the most interesting lines are (IMO) the Northern, Jubilee and Victoria. The Vic is a lot more interesting than its simple route on the Tube Map might initially suggest!
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Post by North End on Apr 6, 2021 13:35:28 GMT
As a result of a figure quoted in the "Clapham narrow platforms " thread, I wondered how much the LU system is worth (in purely monetary terms). To put it another way, how much would it cost to build it from scratch, today. (Ignoring the cost of land acquisition.) Maybe someone here has the knowledge to come up with a sensible guess, but I imagine it would be in the hundreds or billions region. The question of worth is a very interesting point, but you’d also have to consider the extent of liability - namely the amount of ongoing maintenance required for structures like viaducts, bridges and tunnels, and what could happen if something went wrong like a tunnel collapse. I recall getting into conversation with the owner of a property next to a disused railway tunnel in Wales, who remarked how they had thought about purchasing the tunnel as an extension feature to their garden, but when they took legal advice on the practicalities of it the advice was very clearly *don’t do it*! There’s some interesting such structures, like the infilled but not quite properly infilled Bolsover Tunnel in the Midlands, which must now be a very serious liability should something ever happen, especially with houses and public space over the top. There’s other disused tunnels which are in poor condition and unmaintained, such as Burdale and Drewton (both in Yorkshire) but these run mainly beneath fields so aren’t quite so risky. This naturally wouldn’t apply to LU’s assets though.
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Post by North End on Apr 5, 2021 20:09:41 GMT
A potential problem going forward is that if extant staff tend to gravitate away (why wouldn’t you if Hammersmith is locationally inconvenient, the building isn’t great, and the job is a bit less hassle elsewhere?), the Met/C&H is potentially left with all junior / relatively inexperienced staff. I heard this was one of the initial issues with Neasden when it opened. Because the Jubilee line had traditionally relied on the Met for its Service Control staff, there was a need to recruit additional staff for Neasden when it opened, and many of them were new entrants to Service Control with very few (if any) experienced staff moving there. Regarding Hammersmith, on the occasions I've been there I've noticed a few issues with the building. The control room is probably half the size of sports hall at my old school, both in footprint and height. Whereas most other rooms have been at most 1.5 floors high, this is 2 or 2.5x normal ceiling height. There have been issues with the heating, ventilation and air conditioning, there's no natural light, and on my first few visits, the toilets didn't flush. If you're being moved into what is likely to be the Underground's flagship control centre, you would have been forgiven for expecting the building to be reasonably functional when you arrived. I wonder if something has gone slightly awry with the recruitment. For previous places, they have tended to take all the existing signallers and upskill them to controller level, generally some considerable time before actually being needed. This seems to have worked as there’s then been a full roster of people ready for “go live”, all of whom are experienced to at least some level. It seems here there’s been some level of expectation that the established coterie of controllers would prove sufficient. When you’re then talking about a small number of people, things then become rather vulnerable to retirements and the like, Covid then being the straw to break the back. One way or other, realising there’s a problem is the first step towards finding a solution.
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Post by North End on Apr 5, 2021 11:00:33 GMT
The fragmented nature of SSR’s signalling, control and operational setup means it’s more intensive than elsewhere, and it seems the fragile nature of the infrastructure means on top of that it goes up the wall that little bit more often than elsewhere. Surely this is what Hammersmith is meant to solve though? Bringing Controllers and Signallers closer together. Yes and no. Once Hammersmith is complete, though bear in mind there’s already been some descoping, yes there should be some spread of workload. That’s certainly happened at Highgate and Neasden. But, these two places are fully staffed with SCL2s, so anyone can do everything. Hammersmith is unlikely ever to get that, as the cost of having everyone as an SCL2 is too great, and in any case there probably isn’t the training capability to achieve it. You’d expect things to settle down once 4LM is complete, but that’s a *long* way off. Even then there will still be a fair few external interfaces which add elements of complexity - Chiltern, Jubilee from Finchley Road to Wembley, Picc around Acton, NR to Wimbledon and Richmond, etc. It may be the case that a complete rethink of SSR control is needed. Going for a more formal Met / C&H split has been suggested, but I’m not sure how that would actually work in practice.
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Post by North End on Apr 4, 2021 22:51:35 GMT
The first mention in the RMT bulletins was December 2019, local reps would have been making management aware of the issues many months before they passed it up the chain although one of the later complaints was that management were refusing to recognise RMT reps so that might have been part of the problem From my own personal experience as a H&S rep on the JLE stations I can testify to LUL management's ostrich-like approach to accommodation problems; ignore it in the hope it goes away. It’s interesting Hammersmith has run into issues, as most of the other PPP-era rooms have tended to be reasonably satisfactory, even popular. On top of the room issues (I’ve never been there, perhaps luckily enough, so am going to avoid commenting on the room issues as what I’ve heard is largely second hand), there’s also workload issues, specifically for the Met/C&H controllers, though this doesn’t seem to extend to the District. Issues over workload for that role isn’t an entirely new thing, from what I gather it’s been a bit of a long running sore. The fragmented nature of SSR’s signalling, control and operational setup means it’s more intensive than elsewhere, and it seems the fragile nature of the infrastructure means on top of that it goes up the wall that little bit more often than elsewhere. A potential problem going forward is that if extant staff tend to gravitate away (why wouldn’t you if Hammersmith is locationally inconvenient, the building isn’t great, and the job is a bit less hassle elsewhere?), the Met/C&H is potentially left with all junior / relatively inexperienced staff. Meanwhile, if potential entrants to the role get wind of the possibility they are likely to end up at a poison chalice location, people will decide not to bother, unless they are desperate for a pay rise. None of this bodes well, and things could get quite a bit worse if this issue continues to fester.
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Post by North End on Apr 3, 2021 18:29:59 GMT
Surely faster acceleration can negate slightly longer dwell time. I am astonished to learn that S7s have a capped top speed of a mere 48. Even if that is MPH there are (surely) places where higher / perfectly reasonable and of course safe. My thoughts turn to outer suburban branches - Richmond, Wimbledon, Upminster. Not my neck of the woods, however I would imagine any speed caps apply only when under conventional signalling. If being supervised by ATP then there’s no reason for any other limitations. In the same way the 92, 95 (and 96?) stocks all had their performance capped in their early days. In times past it was not uncommon for drivers to have a moment of enjoyment at Brent Cross southbound, which on an empty train was the ideal place to practice entering the platform as fast as possible. The gradient profile there meant it was possible to pass the platform ramp at 40 mph or more, hold the handle in full service for the entire length of the platform, and stop absolutely perfectly on the mark, even on slippery rails. Always done with the starting signal green on approach of course, though you’d have to seriously mess things up to be running past that. Nowadays there’s some platforms which can be entered in this way, all in tunnel of course, but it isn’t quite as satisfying knowing that the ATP system is monitoring every move. Relays start clicking if sailing close to the wind, but I’ve never had the system intervene on a station stop (except once at slow speed at Camden where it’s setup in an odd way).
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Post by North End on Apr 1, 2021 21:34:58 GMT
You're reading far too deeply into it! The whole point of the initial PA's is reassurance. As I mentioned above, the current PA standard was brought in after 7/7 following customer feedback. By making the initial PA we are reassuring customers that there is nothing untoward going on. We are in control and everything is routine and normal. The three minute update is the PA where we should be giving relevant information. There is nothing more frustrating than sitting on a train with a silent driver. I think it's more to the point that LU are seriously underthinking it. Normally trains move along, they stop, they start. Especially on a crowded and complex system like a large metro. Passengers know this and are unlikely to be concerned provided the train starts in a minute or so. It really isn't news that a the train has stopped because a signal is red. Now, when something that is going to cause a serious delay occurs, I seriously doubt that all the drivers held at red signals find out about the situation within 30 seconds and either make the appropriate announcement or inhibit the automatic system from making a false announcement. So we have two situations: One where everything is normal and the information is pointless, because everyone knows that trains stop and start between stations, and the other where there is a real, longer term, problem, and the information is a lie. I've heard that announcement so many times and it has never imparted any information (except, I suppose that the train hasn't stopped because of a cow on the tracks). Instead, every time I hear it I think, "What bloody idiot thought it was a good idea to do that?" I can see two sides to it. Personally I feel 30 seconds is too premature. A minute would be more reasonable, as this would wash away most routine inter-station stops. I don’t see it as particularly professional when the driver comes on the PA, and just at that moment the signal clears and the train moves (especially on the ATO lines where the driver can’t leave it a few more seconds before moving off!) - to me this hardly gives the impression that the driver is on top of things, on the contrary in fact. However a bigger problem is that the 30-second PAs have become so routine, that it might be seen as concerning if you *don’t* hear one, which has a habit of being the case when there’s something actually kicking off, either because the driver is busy doing something else, or in the heat of the moment forgets to make the PA. Personally I’m all for keeping people informed as to what’s going on, however I’d prefer to trust the professional judgement of the £60k driver as to what information is given and when. If the powers that be are concerned about inter-station stops being a matter of apprehension, then there’s other ways of addressing that.
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Post by North End on Apr 1, 2021 1:30:42 GMT
I do wonder, is all this automation really necessary to achieve an additional 2 or 3 trains per hour? The District Railway was achieving 43 TPH and more in the days of steam working and manual semaphore signalling. The answer is probably it depends. Very high frequencies can certainly be achieved with manual driving and conventional signalling, however it requires drivers to perform at a very high skill level, and even then there is the possibility of mistakes happening. Even the absolute best driver at charging into platforms and up to red signals would make a mistake occasionally. Then there’s the issue that signalling standards have tended to tighten over the years, so what might have been seen as an acceptable risk trade-off in the 1960s probably isn’t seen as acceptable now. The higher the speed, the more difficult it is to design an acceptable signalling layout which offers a good throughout. The fundamental benefit of the modern ATP systems is they monitor braking curves, which make it easier to design awkward layouts. This is before one considers ATO which removes the variability of individual drivers - though some would say it achieves this by debasing every train down to the level of the worst drivers. I’m not sure that’s the case for the Central and Victoria lines, but I’m not so sure about Seltrac! In short, I think someone could design a layout using conventional signalling which could theoretically match ATC levels of throughout, however I’m not so sure it would bear up to the challenges of the modern railway, and elements of today’s operating cultures. I’ve chosen my wording very carefully here!
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Post by North End on Apr 1, 2021 1:29:36 GMT
I do wonder, is all this automation really necessary to achieve an additional 2 or 3 trains per hour? The District Railway was achieving 43 TPH and more in the days of steam working and manual semaphore signalling. The answer is probably it depends. Very high frequencies can certainly be achieved with manual driving and conventional signalling, however it requires drivers to perform at a very high skill level, and even then there is the possibility of mistakes happening. Even the absolute best driver at charging into platforms and up to red signals would make a mistake occasionally. Then there’s the issue that signalling standards have tended to tighten over the years, so what might have been seen as an acceptable risk trade-off in the 1960s probably isn’t seen as acceptable now. The higher the speed, the more difficulty it is to design an acceptable signalling layout which offers a good throughout. The fundamental benefit of the modern ATP systems is they monitor braking curves, which make it easier to design awkward layouts. This is before one considers ATO which removes the variability of individual drivers - though some would say it achieves this by debasing every train down to the level of the worst drivers. I’m not sure that’s the case for the Central and Victoria lines, but I’m not so sure about Seltrac! In short, I think someone could design a layout using conventional signalling which could theoretically match ATC levels of throughout, however I’m not so sure it would bear up to the challenges of the modern railway, and elements of today’s operating cultures. I’ve chosen my wording very carefully here!
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Post by North End on Mar 31, 2021 12:05:21 GMT
Even with an infinite pot of money and approval today, such a simulator could not come online for a couple of months absolute minimum, longer if there isn't a suitable room currently sitting empty. If you need to design the simulation software then make that probably at least 6 months. You will then need to train the trainers, given that the training environment is different to what they've used previously - being extremely conservative that's another week minimum. In the real world even emergency approval would take a minimum of 2 months, so you couldn't start training in this suite for at least 5 months more realistically 12 months, by which time there will be less need for legacy system training due to 4LM progress, and reduced or no need for social distancing measures. Something like the TBTC / CBTC simulators are very realistic - each of the modern control rooms has a simulator thrown in as part of it. Certainly Highgate’s training room is massive, so no problem social distancing there. But the problem is this is largely for signalling. The controller role is very different, and much harder to train for as it has to account variables which are only found in the real world. The rooms which have a combined controller/signaller setup have a massive advantage, as they can train someone on the signaller function only, and then use them to cover a live signal desk whilst releasing a qualified controller to cover that function. Hammersmith unfortunately doesn’t have this setup, so is suffering accordingly. Remember also that to train someone up as a TBTC / CBTC signaller is essentially coming up to three months, by the time the person has done their core training, line specific training, and had at least a couple of weeks on the real desk. And that probably assumes someone already has a reasonable knowledge of the line, job roles etc. Where they are suffering on top of this is that Hammersmith has gained a bad reputation as a place to work, for various reasons, and that’s not helping attract people to work there.
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Post by North End on Mar 28, 2021 20:15:43 GMT
I definitely recall this as well. They were certainly used in this way for the Central Centenarian tour in 2000. I forget what the actual arrangements were for that, however it was certainly running under signals. There must have been some serious work gone into the planning for that one. I seem to recall reading somewhere that a Whole Line Possession was taken for the Central line that night in order to facilitate the rail tour running. This I’m assuming would be a modern equivalent of the “One Engine in Steam” principle. I’d love to know how they came up with a method to ensure the train ran at safe speeds, given that the Central Line no longer has speed limits published or displayed trackside. There must have been some serious thought put into the planning. A very memorable night, though, especially the stop at Wood Lane.
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Post by North End on Mar 27, 2021 12:16:06 GMT
I don't think LU has ever had a system where signal aspects appear in the cab. On the Central Line target speed is displayed in the cab and the fixed signals are sort of supplementary. They have definite value and degraded working is one but not the only. However the automatic colour lights that are provided between stations on plain line sections on the Central have always interested me somewhat. I love fixed signals and hate and loathe their removal so I'm not complaining but I've never been quite sure on the stated purpose of their retention after ATP was rolled out. I have read things that suggested there were originally some ideas which were later dropped about perhaps allowing trains without ATP to run on the line as well and the fixed signals were intended for them (I'm talking about the automatic signals between stations specifically) but I dunno really, I suspect they were probably retained for degraded working. The original Victoria Line system had a way of displaying the current code in the cab but the problem was that was all it could display. What it couldn't tell you was that the code was gonna come down before it did. I believe that's why the 67s were limited to 25 mph in Coded. Because the problem was if not you'd be going along at full speed with your 420 code completely fine, then suddenly the train would receive a 180 code and it'd trip. And there was nothing you could do about that so 25 it was.
I seem to recall this too - maybe for engineers' train or special workings. In the end, the engineers' trains were fitted with ATP, so the colour light signals are somewhat pointless. I seem to recall this too - maybe for engineers' train or special workings. In the end, the engineers' trains were fitted with ATP, so the colour light signals are somewhat pointless. I definitely recall this as well. They were certainly used in this way for the Central Centenarian tour in 2000. I forget what the actual arrangements were for that, however it was certainly running under signals. There must have been some serious work gone into the planning for that one.
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Post by North End on Mar 26, 2021 21:21:15 GMT
Some of them did; the white aspect on the corner signals was used at some places (Victoria SB is one) as a kind of 'off' indicator to platform staff, as the signal itself is in the tunnel and hard to see. My apologies if your post wasn't intended to imply otherwise but there were quite a few white aspects on the Victoria Line and by no means limited to platform starting signals (although again I don't know if that's what you meant to imply). And indeed there were plenty of platform starting signals without the white aspects. I always thought the corner signals were originally the only signals and meant for the train operator as much as anyone else, but it was found they were a bit difficult to see from the cab, so co-acters were added in the tunnels later. But maybe that's one of those things you hear that isn't actually true. ^ The last paragraph above is essentially true. I just took the trouble to check the yellow peril for the opening of Stage 1:
But again, I don't assume you didn't already know that!
The extra signal heads appeared as part of the preparation for the 09 stock. Presumably for sighting reasons.
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Post by North End on Mar 23, 2021 7:47:53 GMT
While not an afterthought, it was a temporary fix and was not expected to bu used for more than a couple of years. There was at least one occurrence when a trip re set when the train was moving forward, this caused big issues and a redesign. I may be wrong but I feel convinced that there was a trip reset button in the cab. I haven't been in one for 20+years. Not to my knowledge, just the awful rope arrangement. It certainly wasn’t unknown for the tripcock to not reset, or even for the rope to snap! Looking back it’s incredible the arrangement ever existed. No idea what was provided on the 96 stock, could they have had the button?
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Post by North End on Mar 23, 2021 5:02:30 GMT
There are reasons for having the rear trip operational, however, the 95 stock did not have a rear trip reset button in the front cab and on the S stock the same button resets front and back, resulting in a time delay after resetting before full speed can be achieved. To me it would be sense to be ble to reset the rear trip independently without inhibiting forward movement. The tripcock setup on the 95 stock was odd. The tripcock reset was in the form of a rope, which drivers on occasions had difficulty resetting. Meanwhile the tripcock at the rear end tended to reset itself if activated - so you’d get the brake application, but the train could be driven immediately after stopping with no further intervention required, or at least this happened most of the time! No one seemed to quite know whether this behaviour was intentional or not. I was once told by someone in Alstom that the system behaved according to how much of a hit the tripcock took (ie the faster the train was going the further the arm would travel, which would influence whether it would latch or not). I’ve no idea what the actual design intention was. This wasn’t an issue at the leading end, though there was an issue at one point earlier in the stock’s life. Allegedly the whole tripcock mechanism on the 95 stock was an afterthought, though again that’s dubious as there was surely always the expectation that resignalling would be some time after fleet replacement. One way or other, I think everyone was pleased to get rid of the tripcocks once TBTC came in.
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North End
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Post by North End on Mar 12, 2021 23:44:22 GMT
It's a mixed bag really. For example the EB graph shows a slower CBTC speed from Farringdon to Barbican (30mph vs 40 mph) but few if any trains would reach that speed under legacy signalling. The same applies in reverse too, Farringdon to King's X WB shows a significant uplift in CBTC speed but the train I was on yesterday didn't exceed 35 mph in that area which is comparable to legacy signalling. For the most part SMA 3 feels exactly the same as it did before and any marginal journey time savings are cancelled out by holding time as the service is still running to the existing timetable. When running times are adjusted and timetables recast, I'm sure these differences will become more discernible. Very disappointing that the eastbound is actually slower than before - if it was not for the faster speed between Kings Cross and Farringdon the overall speed limit reduction would have been even more significant! I am baffled as to why there should be any speed limit reductions anywhere - it almost implies that the previous speed limits were not safe, or is it that trains never ever reached the previous limits whilst under CBTC they might have done so - but this happening was felt to be 'undesirable'. My understanding is that the entire section gets remapped to current standards, which does result in some variations to maximum speed, both up and down. This isn’t unique to SSR, every line has had the same, even I believe the Central back in the 1990s. One should not confuse this with Seltrac’s way of regulating the service, which is to calculate and impose a velocity ceiling should the system calculate that a train would otherwise arrive early at its next station. This was very commonly seen on the Northern in the early days, but less so once the upgrade timetables came in. The Vic Line system works differently, originally is calculated a coasting point where the train would shut off and coast to the next station, which is a vastly superior way of doing things, more akin to what a real driver would do. However I have a feeling I read somewhere that the Vic has since had a software change and now does things slightly differently, which would tie in with a difference in train behaviour that I’ve noticed in the last couple of years. I’d certainly be interested if anyone can comment more on this. In short, expect trains on the SSR to run a bit quicker once the proper timetables are in, though the real issue is simply that the Baker Street to Aldgate section handles a lot of trains, all coming from separate origins, so there’s always going to be some bunching. We shouldn’t judge until the system is in place across the board, though from experience on other lines I wouldn’t expect the system to be earth-shattering, especially during disruption. In the meantime, if you want a fast run, you probably will need to be on a train which is running late, and of course which has a clear run. The Hammersmith signalling staff will need to beware of having an on-time train stuck in front of a late one, as in this situation the on time train gets a slow run and further holds up the late one. The way round this is for the signaller to modify the timings of the first train, but it relies on the situation being noticed and the signaller not busy dealing with something else. Incidentally I believe the Northern is in the process of having some speed uplifts as part of the Battersea preparations. I haven’t been around recently, so can’t comment further on this at the present time. 60 mph in the open is a possibility, this has been in the cards for a while.
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North End
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Post by North End on Mar 11, 2021 18:07:01 GMT
There is also the issue than not everyone can cope with nights, they are rostered at most depots and it is in the framework agreement that they have to be worked but many people swap them and have never done them, or even if they have struggle through with no driving between 01.30 and 04.45, asking people in a situation where they cannot get decent sleep is asking for trouble. Also they currently only appear on a roster occasionally, they would be frequent if night tube was included. Yes I don’t really think it’s reasonable to let people sign up to a job where it was well known nights would only be a relatively occasional fixture, to suddenly find they’re cropping up much more often, and in particular in such a way as to always be at weekends. It’s also hardly conducive to wellbeing to have to have to alter the body clock just for two shifts. Without wishing to keep replaying the same record, all this is one of many reasons why Night Tube is not an efficient way of moving a few people around overnight.
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North End
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Post by North End on Mar 8, 2021 19:02:43 GMT
Hmm I rather think people inside trains in India are probably less at risk than those travelling on the roof. Getting back to LUL - does anyone know roughly how many drivers, guards or passengers are known to have fallen off tube trains as a result of that door being left open whilst the train was moving and indeed roughly how many of those died as a result? On page 33 of The City & South London Railway by T.S. Lascelles (Oakwood Press) it is reported that a passenger died in June 1892. A guard was in the habit of inviting passengers to go out onto the platform of the leading coach to watch the engine at work. One unfortunate passenger fell to his death in the tunnel. The guard hid himself and was not found for some time.
There is no reference to any accidents of this nature in Rails Through the Clay.
I believe a guard once got killed at Hendon Central leaning out of the door as the train entered the tunnel. There’s also the incident a few years back involving C stock and the vasectomy, though that was fortunately no real harm done.
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Post by North End on Mar 8, 2021 17:48:48 GMT
It looks like there will be huge incentives for people to engage in the night life scene post June/July. I would wonder if the night tube will return due to demand. Yes I know there are technical and cost implications as to why many would rather it doesn't, but I do feel that in 2022, this argument may be overridden by demand? I suspect it will come down to resource availability, and in particular whether it’s deemed for the best allocation of those resources to be directed towards Night Tube as opposed to other times of day. Especially training resources - there’s a massive training backlog, and it simply doesn’t stack up to use your training resources on people who require the same amount of training as anyone else, but are only 40% productive.
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Post by North End on Mar 4, 2021 21:06:27 GMT
Will the 100 km/h speed ever be reached? (Piccadilly / Central / Bakerloo lines only ... erm, I'd rather not be on a train even trying to reach that speed on the W&C route!!!) Quite possibly. The existing 1973TS was designed for that sort of speed but the 2nd and 3rd stages of field weakening never commissioned due to not enough of the line being signalled appropriately for the speed increase. Some of the Heathrow branch and the Met Uxbridge line can support speeds of that order I think. The 73 stock can just about reach 55-60 mph in a few locations. Heathrow T123 to T5 w/b and Oakwood to Southgate w/b being the favourites. The approach to Hatton Cross w/b used to be a good bet as well, however the signalling doesn’t seem to permit this since the T5 modifications happened. Whilst this used to be common a decade or two ago, this isn’t really seen nowadays.
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Post by North End on Jan 30, 2021 11:58:48 GMT
I do wonder whether a senior member of TFL or one of the Mayor's mates lives nearby to justify the cost and disruption to remove Pandrol fastenings simply because of noise? Meantime Network Rail are busy installing loads of brand new ones on their latest ECML upgrades such as the Werrington dive under, which suggests their Pandrol fastenings are safe to use for trains travelling at 120mph plus! Obviously if there was a clear safety issue to resolve with the specific versions installed by TFL then fine. But we are repeatedly being told that TFL is in dire financial straits so if this work is really only being done just because it is a bit noisy, this decision seems totally absurd. I wonder how long it will be before this decision gets picked up by the media and the Mayor starts facing questions about exactly what is going on, why and how much has it all cost. I wouldn’t think there needs to be anything nefarious about it. They have been the cause of an absolutely massive number of passenger complaints regarding noise, as well as a matter of dispute with drivers also over the noise. A number of things have been tried in an attempt to address this, but have seemingly failed to be effective.
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Post by North End on Jan 20, 2021 19:20:24 GMT
According to Underground News Jan 2021, Battersea remains on time for Autumn 2021 opening, whilst Bank closure has slipped again due to COVID delays to October 2021 - January 2022. I suspect it may end up being a case of whilst Battersea may be able to open from a technical point of view in Autumn, I don’t think it will in practice. If we work on the basis that Bank finishes in January 2022, then this would make it feasible for Battersea to open fairly soon after that. This would also give some additional time for training, which (personal view) I can’t see being completed by Autumn especially with Covid still going on.
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Post by North End on Jan 20, 2021 16:59:42 GMT
"There was a desire that Crossrail should be open before the blockade of the Bank branch happened. Obviously this couldn't happen." Assuming TFL are not intending on waiting for Godot - then with passenger levels already much lower than usual other lines should have capacity to handle diverted passenger flows without Liz-Line. I don't see why the blockade cannot proceed as soon as the new platform and related infrastructure etc is basically ready to be connected up - which sounds like it could be very soon. Sadly if they insist on waiting for the core to open, all that investment could well be sitting around unused until mid decade at the earliest. Time to bite the bullet and just get on with it. Yes from what I’ve been hearing any previous intention to wait for Crossrail before doing the Bank blockade seems to have fallen by the wayside. With reduced passenger numbers it’s probably less of an issue in any case. They can’t wait, as it impinges on Battersea too, that more or less physically cannot be open during the Bank works as it would overload the CX branch in terms of train throughput. From what I gather Battersea is still more or less viable for an opening in line with what has been stated. Whether this turns out to be “we *can* open it if necessary” rather than an actual opening remains to be seen. One issue I could see arising is staff training, still nothing started on that score, and Highgate is in competition with other control rooms for being allocated new control staff. Original plans were Battersea was going to require going from 4 to 5 signal desks (returning to what used to be the case at Cobourg Street), however one struggles to see how this can be achieved in the short term with the training backlog across the board, and the fact that other rooms have vacancies.
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