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Post by superteacher on Aug 25, 2015 7:32:01 GMT
This morning, the Jubilee line is listed as totally suspended due to a signal failure at Stratford. Why is the whole line suspended?
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Colin
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Post by Colin on Aug 25, 2015 10:21:04 GMT
Its computer controlled. No computer = no signalling. Putting ones eggs all in one basket is what LU prefer these days  |
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Post by Dstock7080 on Aug 25, 2015 11:02:51 GMT
This morning, the Jubilee line is listed as totally suspended due to a signal failure at Stratford. Why is the whole line suspended? Total system failure Canary Wharf-Stratford, Jubilee Control Centre unable to see trains or signals. Although trains kept running in other areas, Network Control Centre decided to broadcast Line suspension message. |
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Post by bassmike on Aug 25, 2015 11:17:46 GMT
Unbelievably, this unfortunatly seems to be the way forward nowadays. The robots are taking over from humans.
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rincew1nd
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Post by rincew1nd on Aug 25, 2015 11:47:48 GMT
Although trains kept running in other areas, Network Control Centre decided to broadcast Line suspension message. I'm shocked, I would have expected there to be a good service somewhere! |
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Post by superteacher on Aug 25, 2015 11:52:11 GMT
And I daresay the "trains in service" snapshot showed nearly all trains in service - even though most were stationery!
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Post by marri260 on Aug 25, 2015 12:10:26 GMT
Sounds like a VCC failure if that was the suspension. Can't remember exactly, but seem to remember being told that this only happens once every 7 years or so when I spent time in Neasden SCC.
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Colin
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Post by Colin on Aug 25, 2015 12:25:19 GMT
And I daresay the "trains in service" snapshot showed nearly all trains in service - even though most were stationery! You'd be surprised at what goes on for the 3 hourly snapshot purposes. It's been known to bring a train out of Upminster depot and put it back in again.......whilst it was in the platform it was counted as in service for the relevant snapshot!! |
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Post by superteacher on Aug 25, 2015 12:41:27 GMT
And I daresay the "trains in service" snapshot showed nearly all trains in service - even though most were stationery! You'd be surprised at what goes on for the 3 hourly snapshot purposes. It's been known to bring a train out of Upminster depot and put it back in again.......whilst it was in the platform it was counted as in service for the relevant snapshot!! I've heard it all now . . . |
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Deleted
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Post by Deleted on Aug 25, 2015 12:44:49 GMT
Can't remember exactly, but seem to remember being told that this only happens once every 7 years or so when I spent time in Neasden SCC. Ooooh, it's like winning the lottery  But yes, joking aside, it's supposed to be a very rare event. They have three computers - two of which must agree before any action can be taken. If that condition isn't met, then they shut down as a fail safe. Because of the third computer, there's a fair amount of redundancy, so it shouldn't happen very often. The figure I have is once every eight years, but the point stands. According to an article by LURS: |
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North End
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Post by North End on Aug 25, 2015 12:52:07 GMT
You'd be surprised at what goes on for the 3 hourly snapshot purposes. It's been known to bring a train out of Upminster depot and put it back in again.......whilst it was in the platform it was counted as in service for the relevant snapshot!! I've heard it all now . . . It's always "interesting" how so many trains seem to enter service at times like 11:59, or be withdrawn from service at 12:01. Meanwhile, when planning cancellations, it's often the case that cancellations are arranged on the basis of avoiding trains which should be in service at snapshot times, rather than which trains will cause the least impact to the passenger. This is why, sadly, I take it with a pinch of salt whenever any press release comes out boasting about "improved reliability" or such like. The technology is there to ensure these figures are accurate, but unfortunately the process in place to monitor shapshots (conveniently?) seems to rely on honesty. A sad state of affairs. |
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Deleted
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Post by Deleted on Aug 25, 2015 14:20:39 GMT
It certainly seems that todays Jubilee line signalling system is far more fragile and vulnerable compared to past traditional systems. All too frequently the line has more than its fare share of incidents of total or partial paralysis. It also feels like a slow line compared to the Bakerloo or Victoria for example, where you seem to fly along and only spend the minimal time at a station. I think this attributed to the Jubilee lines tediously drawn out arrival/departure ceremony at the newer stations with the anti-suicide doors along their platforms. These doors appear to be a necessary safety measure nowadays with the increase in some members of the publics desire for devilment and stupid anti-social behaviour. As I've said before, I am all for progress and technology so long as it at the very least equals what it is replacing (although preferably is an improvement). All too often managers are sucked in and mesmerized by the sparkling razzle dazzle digital sale technique, without stopping to check if the system is actually up to the job. I could be more cynical and suggest that dubious financial arrangements may also come into play which override the main objective. Considering the amount of work and money that has been spent on the Jubilee line, it should be one of the most reliable and flagship lines on the network. |
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Post by Deleted on Aug 25, 2015 19:02:02 GMT
All too often managers are sucked in and mesmerized by the sparkling razzle dazzle digital sale technique, without stopping to check if the system is actually up to the job. Complete nonsense. The system was purchased by Tube Lines in the days of PPP when their profit stream was based on performance so they would not have been "sucked in by razzle dazzle" and ignored whether or not they would achieve the required performance. The Jubilee line has had its well publicised ups and down but the system reliability is generally very good indeed and the line's performance scores are dramatically better than a few years ago. I could be more cynical and suggest that dubious financial arrangements may also come into play which override the main objective. . If you have any evidence for that disgraceful and unwarranted assertion then please put it forward. Returning to the OP the cause was a VCC halt - reason unknown as yet - and only affected the Canary Wharf to Stratford area. Trains continued to run on the rest of the line; albeit slowed up by the need to reverse at Canary Wharf and elsewhere. Why a line suspension was advertised i don't know - it hasn't been in similar instances before. |
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Post by linus on Aug 25, 2015 20:21:40 GMT
Leytonstone, when you say "It certainly seems ...", is that from experience? As a regular commuter from Willesden Green, I perceive an entirely different Jubilee Line to the one you describe. Today excepted, it has indeed been a model of reliability for several years, since the initial automation wobbles died down. It has also speeded up dramatically with tbtc; before that, trains would crawl start-stop during the morning peak all the way. Now it is rare for any train to be held, and then generally due to passenger action. When things do go wrong (rarely train or signalling-related), service recovery is generally very rapid.
Deceleration at above-ground stations could be improved slightly, but is hardly worse, if at all, than driven trains. Speeds above ground are fast - 50mph? As fast as the parallel Met and Chiltern trains. Station dwell times are regular; I agree that on the Bakerloo particularly drivers sometimes close doors almost immediately at lightly-used stations; but then have to stand at Queens Park or Paddington to wait right time. Whereas the Jubilee is even.
And I believe the Jubilee has one of the highest passenger satisfaction ratings of any of the underground lines. Rightly so, in my opinion (and I use them all).
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Post by superteacher on Aug 25, 2015 20:26:48 GMT
Leytonstone, when you say "It certainly seems ...", is that from experience? As a regular commuter from Willesden Green, I perceive an entirely different Jubilee Line to the one you describe. Today excepted, it has indeed been a model of reliability for several years, since the initial automation wobbles died down. It has also speeded up dramatically with tbtc; before that, trains would crawl start-stop during the morning peak all the way. Now it is rare for any train to be held, and then generally due to passenger action. When things do go wrong (rarely train or signalling-related), service recovery is generally very rapid. Deceleration at above-ground stations could be improved slightly, but is hardly worse, if at all, than driven trains. Speeds above ground are fast - 50mph? As fast as the parallel Met and Chiltern trains. Station dwell times are regular; I agree that on the Bakerloo particularly drivers sometimes close doors almost immediately at lightly-used stations; but then have to stand at Queens Park or Paddington to wait right time. Whereas the Jubilee is even. And I believe the Jubilee has one of the highest passenger satisfaction ratings of any of the underground lines. Rightly so, in my opinion (and I use them all). I would echo these sentiments. In my experience, the Jubilee line is much quicker than the Bakerloo. |
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Post by londonstuff on Aug 25, 2015 20:59:17 GMT
Leytonstone - what a negative post! On the extension the 'anti-suicide doors' aren't actually that at all, they were included at the time of building to reduce the amount of air flow in stations. I think this was also mentioned in the Driver's Eye View DVD. Elements of what you say could be true - with the SSR signal contract, for example, the technology wasn't up to the complexity of the system and had to be retendered. As Tridentalx alludes to, the Jub did suffering the beginning, mainly as their system had only ever been installed on brand new lines before. Personally, I'm surprised they can't fit more TPH on the Jub given the modern signalling, three platform terminal stations and no real branches, but I think that's been discussed elsewhere before. Chill, man  |
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Post by marri260 on Aug 25, 2015 22:01:27 GMT
I'd go as far as saying that the Jubilee is now extremely reliable, I generally find it a pleasure to use on a daily basis. Only twice in the past two years has a service disruption forced me to take an alternative route when I intended to use the Jubilee. Granted, when things go wrong then it normally causes a complete hold up until the source of the problem is rectified, but that is just the way it has to be now with the ATC system.
The only thing currently holding the line back from operating over 30tph is the size of the fleet, which in all truth, probably isn't quite big enough even for the 30tph service. The 96TS certainly aren't Improving in reliability, as they get a heavy workload put on them, it certainly isn't uncommon for the Jubilee to have cancellations due to the rolling stock. One morning back in May, they cancelled 7 trains in the morning peak, but still managed to maintain a 'good service' but one suspects that it probably wasn't truthfully 'good'. Obviously TfL have plans in place to eventually increase the service up to 36tph by increasing the size of the fleet as has been discussed on here before.
I'd also be very surprised if 36tph could be run with the current tipping out at Willesden Green and Wembley Park blocking the road. Stanmore is over provided as it is, let alone with even more trains potentially being sent up there so don't think that is the answer but it may be the only feasible option.
Again, during my time at Neasden SCC I was told that 38tph has once been run, and is the current 'record'. It was apparently achieved during service recovery, but no idea if this is true or not. Considering the position of who told me, I'd be surprised if it wasn't. It was also mentioned that if the fleet size were to be increased, it would be difficult to find somewhere to put the extra trains, as there isn't currently much free stabling space. The general consensus seemed to be that increasing capacity at Stanmore is the most likely option, as the Met would if anything prefer to have less Jubilee trains in Neasden rather than more, and not really much more that can be done at SMD.
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Post by North End on Aug 25, 2015 22:40:32 GMT
Leytonstone - what a negative post! On the extension the 'anti-suicide doors' aren't actually that at all, they were included at the time of building to reduce the amount of air flow in stations. I think this was also mentioned in the Driver's Eye View DVD. Elements of what you say could be true - with the SSR signal contract, for example, the technology wasn't up to the complexity of the system and had to be retendered. As Tridentalx alludes to, the Jub did suffering the beginning, mainly as their system had only ever been installed on brand new lines before. Personally, I'm surprised they can't fit more TPH on the Jub given the modern signalling, three platform terminal stations and no real branches, but I think that's been discussed elsewhere before. Chill, man It isn't correct that Seltrac has only ever been installed on new systems. It was, of course, retrofitted to the DLR in the early 1990s. Personally I think Seltrac, as we currently see on the Jubilee and Northern, will struggle to achieve much above the TPH it currently achieves. Stockwell southbound now blocks back in the evening peak far worse than it did under the old signalling, with not a massive increase in frequency. There are plenty of places where the driver would previously have been halfway towards the platform with a string of green home signals, where under TBTC the train still hasn't even started moving. Worse in the open sections where you then waste more time with the pathetic gentle brake rate. |
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Post by Deleted on Aug 26, 2015 0:38:47 GMT
It certainly seems that todays Jubilee line signalling system is far more fragile and vulnerable compared to past traditional systems. An interesting observation - I wonder what makes you say that? There's certainly a lot that can go wrong with good old-fashioned colour-light signalling - even something as simple as a lamp failure. There are a lot of moving parts with traditional systems and the fact that TBTC does away with a lot of line side assets should certainly help reduce its fragility. It also has quite a bit of redundancy, e.g. the two VOBCs (Vehicle On Board Controllers) on every train and the three computers that make up each VCC (Vehicle Control Centre). One of the weak points, of course, is the two orange wires, which are a wee bit too cut-through-able. Having said that, each loop can apparently "sustain a flat-bottom rail being dropped on it from 2 metres in height, people walking on it, rain, etc." ( The Jubilee Line Upgrade - LURS) All too frequently the line has more than its fare share of incidents of total or partial paralysis. Again, I'm not entirely sure I can agree with this. One of the problems, though, is that - as has been mentioned - most of the eggs are distributed among very few baskets. Also, the way that the system works is quite 'all or nothing'. In the old days, failures tended to be actually fairly common, but more confined. With TBTC, the system works by frequent (once per second) communication between all trains in an area and the VCC responsible. The trains send information, such as their position, to the VCC. It then sends instructions to the trains. Because the VCC knows where the trains are, it can calculate the appropriate speed for each train to travel at to keep them all a safe distance apart. If one train falls off the system, then it (the train) has no way of knowing where other trains in the area or, or how fast it is permitted to travel. This means that it has to be restricted to 17.5 kph and driven on line of sight, until it can re-enter the system. If, however, the VCC fails, well then you have a bit more of a problem, because the whole basis of the system goes out of the window (communication between the trains and the VCC). Then everyone has to be restricted to 17.5 kph. Because VCCs look after quite big areas, it can mean disruption to quite a large area. But such disruption is quite rare, as we've said already. It also feels like a slow line compared to the Bakerloo or Victoria for example, where you seem to fly along and only spend the minimal time at a station. I think this attributed to the Jubilee lines tediously drawn out arrival/departure ceremony at the newer stations with the anti-suicide doors along their platforms. These doors appear to be a necessary safety measure nowadays with the increase in some members of the publics desire for devilment and stupid anti-social behaviour. As I've said before, I am all for progress and technology so long as it at the very least equals what it is replacing (although preferably is an improvement). Hmmm, "slow" seems a strange choice of adjective to me. Line speeds on the Jubilee are actually really quite high. I'm not sure what the average line speed is - nor the maximum - but I can tell you that the Working Time Table lists off-peak running time as 57 minutes in the northbound direction. This is a distance of 38.03 km and so that's an average speed of 40 kph which is about 25 mph. By way of comparison the entire length of the Bakerloo line is 23.23 km and the off-peak running time is 48 minutes in the northbound direction. So that's an average speed of 29 kph, which is about 18 mph. The Vic really does shift, mind you. One thing you may have been noticing - as has also already been mentioned - is that the Seltrac system currently uses quite a low brake rate in the open sections. This is a precautionary measure against station overruns, intended for conditions of low adhesion. At the present time, the brake rate for the open sections is always left at a gentle setting, even though the system is capable of stopping more quickly in good conditions. This is a bit of a nuisance. It's not really got much to do with the platform edge doors, though, which shouldn't represent much of a problem for Auto. Indeed, we managed fine with them when we had manual driving as well. You do need to be accurate, for obvious reasons. But then, there are a number of CSDE loops on the network which aren't exactly as long as a canoe, either. According to the Video125 Driver's Eye View, one must stop accurately to within half a metre, which is very much possible for Auto and human alike, without taking an inordinately long time. Video125 have been known to make mistakes, though, and half a metre sounds very generous, though I guess it must surely equate to 25 cm either side of the ideal stopping point, which seems fair. Another thing to bare in mind is the relative busy-ness of stations. Busier stations means longer dwell times (or very unhappy passengers), quieter stations means shorter dwell times. On the extension the 'anti-suicide doors' aren't actually that at all, they were included at the time of building to reduce the amount of air flow in stations. I think this was also mentioned in the Driver's Eye View DVD. This is quite true. As Rob Curling puts it: It's worth noting that they were not provided at the overground stations on the extension, nor were they retrofitted to any other part of the line. However, the PTI (Platform Train Interface) is where most incidents on the tube occur and PEDs are being increasingly looked at as an important potential solution. I am not actually, personally, a huge fan of PEDs, but if they keep accidents down, then that's a very important factor to keep in mind. It's not just bad behaviour that causes PTI incidents! All too often managers are sucked in and mesmerized by the sparkling razzle dazzle digital sale technique, without stopping to check if the system is actually up to the job. I could be more cynical and suggest that dubious financial arrangements may also come into play which override the main objective. Considering the amount of work and money that has been spent on the Jubilee line, it should be one of the most reliable and flagship lines on the network. I think @tridentalx - who has a lot of experience with the system - has made some very fair comments, however, we like to be a bit more accommodating and friendly, especially towards newer members. I'm very glad to have you here, I just need you to remember that there are a number of experienced railway professionals here. This site prides itself on being the premier place for serious, informed discussion about London Underground (and a few other railways in London as well). We don't generally go for conspiracy theories here. If you remember that simple rule, I'm sure you'll do just fine. As you can probably tell from a few avatars, there are plenty of people here who share your appreciation for the traditional, older aspects of LU.And, you know, for what it's worth, I'm going to have to go against the grain here. I don't personally relish the present Jubilee line experience much. Bring back the tripcock? Sadly, I think that horse has well and truly bolted. |
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North End
Beneath Newington Causeway
Posts: 1,769
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Post by North End on Aug 26, 2015 7:08:24 GMT
It certainly seems that todays Jubilee line signalling system is far more fragile and vulnerable compared to past traditional systems. An interesting observation - I wonder what makes you say that? There's certainly a lot that can go wrong with good old-fashioned colour-light signalling - even something as simple as a lamp failure. There are a lot of moving parts with traditional systems and the fact that TBTC does away with a lot of line side assets should certainly help reduce its fragility. It also has quite a bit of redundancy, e.g. the two VOBCs (Vehicle On Board Controllers) on every train and the three computers that make up each VCC (Vehicle Control Centre). One of the weak points, of course, is the two orange wires, which are a wee bit too cut-through-able. Having said that, each loop can apparently "sustain a flat-bottom rail being dropped on it from 2 metres in height, people walking on it, rain, etc." ( The Jubilee Line Upgrade - LURS) All too frequently the line has more than its fare share of incidents of total or partial paralysis. Again, I'm not entirely sure I can agree with this. One of the problems, though, is that - as has been mentioned - most of the eggs are distributed among very few baskets. Also, the way that the system works is quite 'all or nothing'. In the old days, failures tended to be actually fairly common, but more confined. With TBTC, the system works by frequent (once per second) communication between all trains in an area and the VCC responsible. The trains send information, such as their position, to the VCC. It then sends instructions to the trains. Because the VCC knows where the trains are, it can calculate the appropriate speed for each train to travel at to keep them all a safe distance apart. If one train falls off the system, then it (the train) has no way of knowing where other trains in the area or, or how fast it is permitted to travel. This means that it has to be restricted to 17.5 kph and driven on line of sight, until it can re-enter the system. If, however, the VCC fails, well then you have a bit more of a problem, because the whole basis of the system goes out of the window (communication between the trains and the VCC). Then everyone has to be restricted to 17.5 kph. Because VCCs look after quite big areas, it can mean disruption to quite a large area. But such disruption is quite rare, as we've said already. It also feels like a slow line compared to the Bakerloo or Victoria for example, where you seem to fly along and only spend the minimal time at a station. I think this attributed to the Jubilee lines tediously drawn out arrival/departure ceremony at the newer stations with the anti-suicide doors along their platforms. These doors appear to be a necessary safety measure nowadays with the increase in some members of the publics desire for devilment and stupid anti-social behaviour. As I've said before, I am all for progress and technology so long as it at the very least equals what it is replacing (although preferably is an improvement). Hmmm, "slow" seems a strange choice of adjective to me. Line speeds on the Jubilee are actually really quite high. I'm not sure what the average line speed is - nor the maximum - but I can tell you that the Working Time Table lists off-peak running time as 57 minutes in the northbound direction. This is a distance of 38.03 km and so that's an average speed of 40 kph which is about 25 mph. By way of comparison the entire length of the Bakerloo line is 23.23 km and the off-peak running time is 48 minutes in the northbound direction. So that's an average speed of 29 kph, which is about 18 mph. The Vic really does shift, mind you. One thing you may have been noticing - as has also already been mentioned - is that the Seltrac system currently uses quite a low brake rate in the open sections. This is a precautionary measure against station overruns, intended for conditions of low adhesion. At the present time, the brake rate for the open sections is always left at a gentle setting, even though the system is capable of stopping more quickly in good conditions. This is a bit of a nuisance. It's not really got much to do with the platform edge doors, though, which shouldn't represent much of a problem for Auto. Indeed, we managed fine with them when we had manual driving as well. You do need to be accurate, for obvious reasons. But then, there are a number of CSDE loops on the network which aren't exactly as long as a canoe, either. According to the Video125 Driver's Eye View, one must stop accurately to within half a metre, which is very much possible for Auto and human alike, without taking an inordinately long time. Video125 have been known to make mistakes, though, and half a metre sounds very generous, though I guess it must surely equate to 25 cm either side of the ideal stopping point, which seems fair. Another thing to bare in mind is the relative busy-ness of stations. Busier stations means longer dwell times (or very unhappy passengers), quieter stations means shorter dwell times. On the extension the 'anti-suicide doors' aren't actually that at all, they were included at the time of building to reduce the amount of air flow in stations. I think this was also mentioned in the Driver's Eye View DVD. This is quite true. As Rob Curling puts it: It's worth noting that they were not provided at the overground stations on the extension, nor were they retrofitted to any other part of the line. However, the PTI (Platform Train Interface) is where most incidents on the tube occur and PEDs are being increasingly looked at as an important potential solution. I am not actually, personally, a huge fan of PEDs, but if they keep accidents down, then that's a very important factor to keep in mind. It's not just bad behaviour that causes PTI incidents! All too often managers are sucked in and mesmerized by the sparkling razzle dazzle digital sale technique, without stopping to check if the system is actually up to the job. I could be more cynical and suggest that dubious financial arrangements may also come into play which override the main objective. Considering the amount of work and money that has been spent on the Jubilee line, it should be one of the most reliable and flagship lines on the network. I think @tridentalx - who has a lot of experience with the system - has made some very fair comments, however, we like to be a bit more accommodating and friendly, especially towards newer members. I'm very glad to have you here, I just need you to remember that there are a number of experienced railway professionals here. This site prides itself on being the premier place for serious, informed discussion about London Underground (and a few other railways in London as well). We don't generally go for conspiracy theories here. If you remember that simple rule, I'm sure you'll do just fine. As you can probably tell from a few avatars, there are plenty of people here who share your appreciation for the traditional, older aspects of LU.And, you know, for what it's worth, I'm going to have to go against the grain here. I don't personally relish the present Jubilee line experience much. Bring back the tripcock? Sadly, I think that horse has well and truly bolted. I don't think it's fair to make any speed comparison between the Bakerloo and Jubilee. One line was built in the early-1900s, required to run mostly beneath roads, and with many sharp curves as a result. By contrast most of the Jubilee was not constrained by this, and was specifically designed and aligned for high-speed running. So the Jubilee really should have a faster average speed. A comparison between the Jubilee and Victoria lines is more valid. We wait to see if the Jubilee will be able to match the Vic's 34tph, reliably delivered on a daily basis. Looking at the Victoria Line, one sees no gentle brake rate at certain tunnel platforms for no good reason (eg Oval, Chalk Farm, Mornington Crescent, Archway, Highgate, King's Cross, Camden Town, Moorgate, Waterloo, Leicester Square, TCR), no annoying wait of a second or more at every station for the train to get 'AS' before the driver can open the doors, no speed dropping in the middle of nowhere because Thales has failed to deliver a glitch-free system, and a superior ATO experience. |
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Post by superteacher on Aug 26, 2015 7:14:29 GMT
if we want to discuss the pros and cons of different signalling systems, ATO or otherwise, can we start a new thread please. It's been discussed elsewhere in the past. Thanks.
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Tom
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Signalfel?
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Post by Tom on Aug 26, 2015 20:17:21 GMT
If I may add, on the subject of VCCs?
I've done the VCC operator's course and to bring up a VCC from scratch, even on the simulator, takes around an hour. You have to check what restrictions (if any) need to be applied, and this isn't easy as all the text scrolls past you and you can't go backwards. It's probably easier on the simulator, to be honest.
When you enter the command to actually put it into service you don't take the decision lightly. I'm not surprised if it's a protracted delay!
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Post by bruce on Aug 26, 2015 20:21:38 GMT
Yes the Jubilee line may be faster but it has't got many 20 mph curves like the Bakerloo line has and also the station spacing is closer in the tube section of the Bakerloo line.
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Post by superteacher on Aug 26, 2015 20:21:49 GMT
Some good replies on this thread which have really helped to show why the whole line descends into chaos when the system goes down. If it happens once every 7-8 years, this discussion shouldn't resurface until 2022 - 2023!
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Deleted
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Post by Deleted on Aug 27, 2015 6:27:38 GMT
If I may add, on the subject of VCCs? I've done the VCC operator's course and to bring up a VCC from scratch, even on the simulator, takes around an hour. You have to check what restrictions (if any) need to be applied, and this isn't easy as all the text scrolls past you and you can't go backwards. It's probably easier on the simulator, to be honest. When you enter the command to actually put it into service you don't take the decision lightly. I'm not surprised if it's a protracted delay! My understanding is that it took something like 15 minutes to bring the VCC back up which is about what I would expect. Agreed if there are lots of TSRs or other restrictions this could take longer. The time consuming part can be re-entering all the trains onto the system. This will be quicker with the radio technology used for SSR. |
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towerman
My status is now now widower
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Post by towerman on Aug 28, 2015 11:25:43 GMT
And I daresay the "trains in service" snapshot showed nearly all trains in service - even though most were stationery! You'd be surprised at what goes on for the 3 hourly snapshot purposes. It's been known to bring a train out of Upminster depot and put it back in again.......whilst it was in the platform it was counted as in service for the relevant snapshot!! Used to do the same at SMD,if the snapshot was coming up they'd put a train on West Ham reception road,it'd shown up as on the line,then run it back to a stabling road. |
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