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Post by A60stock on Apr 7, 2016 8:36:59 GMT
(This was originally posted in the Signals now on the central line thread)I have always wondered and please correct me if i am wrong: Out of the lines currently automated The Central can be driven in manual at certain times at full line speed in passenger service The Jubilee, Northern and Victoria can only be driven in manual when the top speed is severely restricted (not sure if this is done in passenger service) If this is correct, why is the central allowed to be driven in manual e.g. on Sundays whereas the other lines are always operating under ATO?
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North End
Beneath Newington Causeway
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Post by North End on Apr 7, 2016 8:45:53 GMT
I have always wondered and please correct me if i am wrong: Out of the lines currently automated The Central can be driven in manual at certain times at full line speed in passenger service The Jubilee, Northern and Victoria can only be driven in manual when the top speed is severely restricted (not sure if this is done in passenger service) If this is correct, why is the central allowed to be driven in manual e.g. on Sundays whereas the other lines are always operating under ATO? All the lines can now be driven manually at normal speed if desired/required. The exception was the old Victoria Line which was limited to 22 mph (or was it 25, can't recall?). The reason for the latter was simply that there was no means of the driver being given advance warning of a forthcoming drop in speed - whereas all the current systems do this. All the lines officially have guidelines over when and where drivers should drive manually to preserve skills, normally Sundays. The main issues are a potential increased risk of errors, and lost time. Generally no one minds manual driving at any time providing it doesn't cause issues - naturally some drivers prefer to do it more than others.
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Post by goonerkeith on Apr 7, 2016 10:01:24 GMT
So on the Northern Line with no visible colour light signals at all, how does the driver know when it is safe to proceed? I'm assuming there is some sort of in-cab display. What happens if this fails?
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Deleted
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Post by Deleted on Apr 7, 2016 11:48:48 GMT
So on the Northern Line with no visible colour light signals at all, how does the driver know when it is safe to proceed? I'm assuming there is some sort of in-cab display. What happens if this fails? There is indeed a Train Operator Display. Some more information about it, including a picture, can be found on this thread. Basically, that red line you can in tridentalx's picture see shows you your permitted speed. Obviously when it's zero, as in the picture, it isn't safe to proceed. When it's more than zero it is. Your speed is shown as a yellow bar which moves horizontally along the screen. As you approach the target speed it will go orange. In the top right corner, where the countdown timer is in the picture (0:23 in yellow) you will also have a blue rectangle showing your distance to go. Let's say you're going along and you're notified that the target speed is coming down, say to 20. This information will be displayed in the form of a 20 speed limit sign in the middle, where the AS (accurate stop) is in the picture. In the blue rectangle, you have the distance until you need to be doing 20. That's gonna gradually drop off obviously. If the 20 has been commanded because of a train ahead and that train moves off, your DTG will be updated accordingly. So, let's say the 20 is for a permanent speed restriction. As you approach the speed restriction, your DTG will drop, obviously. As it drops, the red "hand" will start to make its way down too and you will have to stay under it. So now you're at 20. Let's say there's no restriction on your train and you're clear all the way up to where the speed limit rises to 30 and it's all clear beyond that. Well, now your DTG is going to display the distance until you no longer need to be doing 20 - the point where the speed restriction rises. Obviously, your DTG will count down as you approach that point and then when you get there, the red hand will jump up and you can accelerate to match it. If the DTG is more than, I think, 500 m, it just shows 500 +. What if it fails? In Auto, you carry on to the next platform and inform the line controller. If you can't clear the fault, you withdraw the train from service. If necessary, the signaller will authorise you to depart in Auto. You will take it to be mended. In PM you inform the controller and you stop in a safe position. If you can't clear the fault, you have to withdraw the train from service and the signaller will authorise you (if necessary) to continue, out of service, in Auto to get the train mended. How exactly you get to the next platform in order to get everyone off and take the train out of service, I'm not sure. You'll be acting on controller's instructions, so presumably you'll be instructed to proceed in Auto until the next station, tip everyone off and then continue, in Auto, when authorised by the signaller, if necessary. If Auto is not available, you will be authorised to proceed by the signaller at a reduced speed.
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Post by stapler on Apr 7, 2016 12:46:59 GMT
Are Saturdays on the Central Line sometimes also authorised for manual?
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Post by Deleted on Apr 7, 2016 12:54:38 GMT
Are Saturdays on the Central Line sometimes also authorised for manual? There are a range of conditions under which you will be asked or required to go Coded, such as possible obstruction on the line, extremely poor weather, incident in progress on the platform, certain faults and failures, that kind of thing. One of the classics is when passing through 2 consecutive closed stations, as Auto is not capable of doing this. And, of course, many reversing manoeuvres have to be done in Coded as well. Otherwise, you are permitted to go Coded east of Leytonstone and west of White City outside the busier times of day, as long as you don't hold the service up. In theory, you're supposed to ask permission, but if it's a nice day, it's quite common for people to go Coded with door open and, frankly, who cares? At the other end of the spectrum, if the weather is bad/there's a little light rain in the air/a mouse has urinated on one of the running rails, Auto is quite likely to mess up its stops and so it's quite common for people to give up on it and drive in Coded even without being expressly instructed to do so, and nobody really cares. You are supposed to go Coded east of Leytonstone and west of White City on Sundays, but not everybody always does.
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Post by stapler on Apr 7, 2016 13:02:11 GMT
Most interesting, Tut. From the point of view of the passenger, is there any way of knowing if a particular train is being driven manually? I sometimes observe that the old "speed up, longer platform break for tea/fag/wee" technique is being used, and sometimes I suspect the 62mph line speed limit is being breached... Or is all this subject to Big Brother regulation by line control nowadays?
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North End
Beneath Newington Causeway
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Post by North End on Apr 7, 2016 13:39:15 GMT
Most interesting, Tut. From the point of view of the passenger, is there any way of knowing if a particular train is being driven manually? I sometimes observe that the old "speed up, longer platform break for tea/fag/wee" technique is being used, and sometimes I suspect the 62mph line speed limit is being breached... Or is all this subject to Big Brother regulation by line control nowadays? If you listen to the sounds of the brakes applying/releasing before and after the train moves, you can detect a slight difference. Otherwise, it depends on how the individual driver chooses to drive. Some may emulate the ATO very closely, in which case it's hard to tell the difference. Others may coast more or anticipate the road ahead a little and adjust speed accordingly. Another way of telling is whether the train stops with a jolt - the only current ATO system which delivers a reasonably smooth stop is the Central Line. Some drivers may make the effort to throw the brakes off at the last minute, which is very noticeable. Another thing is some drivers may start off on half motors for the first few seconds, to avoid the jolt when the train moves off. Much will depend on whether the train is on time or not - if running late there's less opportunity for play! With Seltrac the driver has a good chance of being able to beat ATO timings, as the ATO has a nasty habit of over-braking for drops in speed, hovering at a too-low speed for a few seconds and then motoring to catch up, whereas in PM this can be avoided if the driver judges it right. It has to be said, however, some drivers are abysmal in PM!
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Deleted
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Post by Deleted on Apr 7, 2016 13:40:53 GMT
Most interesting, Tut. From the point of view of the passenger, is there any way of knowing if a particular train is being driven manually? I sometimes observe that the old "speed up, longer platform break for tea/fag/wee" technique is being used, and sometimes I suspect the 62mph line speed limit is being breached... Or is all this subject to Big Brother regulation by line control nowadays? Well, obviously you can look through the window as the train pulls in and you can usually tell if the TBC is in stow, or if its out and in use. That obviously only means it was being driven manually when it arrived, the driver may have switched it back into Auto, but that's usually your biggest clue. If you're lucky, you might hear the ATP chimes over the PA, which you will only hear in Coded, they don't sound in Auto. Otherwise the only way you can really tell is through your bottom. Human driving does tend to feel a little different. Stops are very often softer, there's less of a jerk, but the rate of deceleration is more variable. Auto tends to brake almost constantly, before easing off right at the last moment, whereas with humans, there's more variability, the braking is frequently less hard, and sometimes the train will almost rock as the amount of braking is varied. There are other things, too. Humans tend to coast more, especially on the approach to red signals/0 target speeds, they tend to be a little more intelligent and the ride feels less jerky. Auto tends to drive as fast as possible and brake as late as possible and accelerate as hard as possible. Humans, less so. Auto also always accelerates away from a station as quickly as it can, whereas some humans accelerate more gradually. However, especially with the nature of the display and the variability of the target speed, you may find humans stabbing at the brakes to keep the speed under the target a little more often, and similar with the motors. Auto can be more consistent, I would have to concede. Not always, some Central line drivers are absolutely superb, but sometimes. However, the best your bottom can give you is an informed estimate, the only people who really know are the driver, and the people up in Wood Lane, who can see on their diagrams what mode their trains are in. The ceiling is 85 kph - 53 mph - post Chancery Lane. It can get pretty choppy up there, but I would doubt that ceiling is being exceeded. As you know, following a software update, Auto cannot exceed 85, but the target speed will get to 100 and the ATP will allow humans to drive that fast, but you would be in serious trouble if you got caught doing that and everybody knows that. There's no good reason for anyone to take that risk. The ATP however will not allow you to get much faster than 100 kph (62 mph).
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Post by stapler on Apr 7, 2016 13:47:24 GMT
My best clue on "down" trains is on the approach to Loughton, where auto begins the braking at Felsted Rd (by the playground, where there used to be a cattle creep underpass), but human drivers often do not. As to speeds, I shall have to check with a stop watch! Would you get caught at 60mph, do you think? Is there actually any routine check?
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Post by Deleted on Apr 7, 2016 14:56:31 GMT
Are Saturdays on the Central Line sometimes also authorised for manual? I thought it was Sunday's and Bank Holiday's
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Post by patrickb on Apr 7, 2016 18:37:48 GMT
The present Central Line signalling comes with two aspect and three aspect signals which I presume makes operating in Coded Manual more simple and thus explain why the Central permits Manual running on Sunday's and Bank Holiday's? or could there be an underlying reason? Either way, why isn't this put into practice on other Lines with ATO signalling?
Does the Seltrac Signalling on the Jubilee and Northern Line and in future the SSL obviate the need for Lineside signals? Is it technically feasible to install line side signals?
Also, partially unrelated to topic (feel free to move this to the correct thread) Could Engineering trains from Ruislip be used in future on the Pic/Met as well as Central considering that there will be different types of signalling in use? At present are these Engineering trains operated manually?
Sorry for asking all these questions, I'm not an expert in signalling or any of this Modern Day Technology Malarkey.
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Post by Deleted on Apr 7, 2016 18:55:06 GMT
The present Central Line signalling comes with two aspect and three aspect signals which I presume makes operating in Coded Manual more simple and thus explain why the Central permits Manual running on Sunday's and Bank Holiday's? or could there be an underlying reason? The colour light signals can't really be said to make Coded Manual more simple in themselves, I wouldn't say. They're installed at junctions, where their route indicators are valuable, but that's not really that big a deal. They're installed at stations, where they are definitely a nice feature, because you can glance at a big colour light, but that goes for Auto as well. Then there are the remaining ones in between, which aren't that plentiful. I have read that the main reason for their installation was early suggestions of possibly running non-ATP fitted trains, such as engineers trains, to colour light signals, but that was abandoned. That may just be a rumour, though, and mainly they're useful for trains in RM. The rest of the time, I mean, the light doesn't tell you the target speed. Well, the red light does tell you that the target speed is zero, but the white and green lights do not give you the target speed. Also, the red light may be some distance away when you first see it and there may be a few block marker boards between you and it at which the target speed will be checked down, so it's the in cab display that really matters. The colour lights are presumably a nice thing to aim for, slightly easier to see than a block marker board maybe? I've never driven a Central line train, but it hardly seems plausible that this is a major factor. You could have only block marker boards and it wouldn't make a huge difference to Coded Manual or Auto operation, really. It would make both of them slightly less ergonomic, as I say, the colour lights are great as station starters and handy at junctions, but it wouldn't have a huge effect on how you drive. It'd make RM operation impossible though! What is a major factor is fixed block signalling. Them block marker boards and signals don't move, they're always in the same place, and you have a fixed target to aim at. The target speed drops in managed stages. The target speed and target point aren't constantly updating and changing and moving. The system is also less of a pig and it doesn't enforce its driving style on you as much. It gives you the speed you should be doing and the lineside signage and signals give you the point at which you should be doing that speed and then it leaves you to achieve that goal in your own way. Either way, why isn't this put into practice on other Lines with ATO signalling? As stated above by North End it more or less is. Does the Seltrac Signalling on the Jubilee and Northern Line and in future the SSL obviate the need for Lineside signals? Is it technically feasible to install line side signals? Yes it does obviate the need for lineside signals. Route secure visuals are provided wherever there are points for degraded working, but that's all you need. Lineside signals do not integrate very well into moving block signalling and would be of very little value. They would just be expensive to install and maintain and offer no return. RM hold boards suffice for degraded conditions. Also, partially unrelated to topic (feel free to move this to the correct thread) Could Engineering trains from Ruislip be used on the Pic/Met as well as Central considering that there will be different types of signalling in use? Are these trains operated manually? It depends on the individual train and what equipment it's fitted with. They are operated manually.
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Post by superteacher on Apr 7, 2016 18:55:58 GMT
The present Central Line signalling comes with two aspect and three aspect signals which I presume makes operating in Coded Manual more simple and thus explain why the Central permits Manual running on Sunday's and Bank Holiday's? or could there be an underlying reason? Either way, why isn't this put into practice on other Lines with ATO signalling? Does the Seltrac Signalling on the Jubilee and Northern Line and in future the SSL obviate the need for Lineside signals? Is it technically feasible to install line side signals? Also, partially unrelated to topic (feel free to move this to the correct thread) Could Engineering trains from Ruislip be used in future on the Pic/Met as well as Central considering that there will be different types of signalling in use? At present are these Engineering trains operated manually? Sorry for asking all these questions, I'm not an expert in signalling or any of this Modern Day Technology Malarkey. I believe that engineering trains have been equipped with Central line ATP for some time. Not sure about other systems.
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Post by Deleted on Apr 7, 2016 19:14:09 GMT
Lineside signals will only remain on the fast lines north of Harrow on The Hill for the Chilterns and on the 4 track between Barons Court and Hanger Lane Junction and of course the Wimbledon and Richmond Lines
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Deleted
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Post by Deleted on Apr 7, 2016 20:25:57 GMT
Most interesting, Tut. From the point of view of the passenger, is there any way of knowing if a particular train is being driven manually? I sometimes observe that the old "speed up, longer platform break for tea/fag/wee" technique is being used, and sometimes I suspect the 62mph line speed limit is being breached... Or is all this subject to Big Brother regulation by line control nowadays? Well, obviously you can look through the window as the train pulls in and you can usually tell if the TBC is in stow, or if its out and in use. That obviously only means it was being driven manually when it arrived, the driver may have switched it back into Auto, but that's usually your biggest clue. If you're lucky, you might hear the ATP chimes over the PA, which you will only hear in Coded, they don't sound in Auto. Otherwise the only way you can really tell is through your bottom. Human driving does tend to feel a little different. Stops are very often softer, there's less of a jerk, but the rate of deceleration is more variable. Auto tends to brake almost constantly, before easing off right at the last moment, whereas with humans, there's more variability, the braking is frequently less hard, and sometimes the train will almost rock as the amount of braking is varied. There are other things, too. Humans tend to coast more, especially on the approach to red signals/0 target speeds, they tend to be a little more intelligent and the ride feels less jerky. Auto tends to drive as fast as possible and brake as late as possible and accelerate as hard as possible. Humans, less so. Auto also always accelerates away from a station as quickly as it can, whereas some humans accelerate more gradually. However, especially with the nature of the display and the variability of the target speed, you may find humans stabbing at the brakes to keep the speed under the target a little more often, and similar with the motors. Auto can be more consistent, I would have to concede. Not always, some Central line drivers are absolutely superb, but sometimes. However, the best your bottom can give you is an informed estimate, the only people who really know are the driver, and the people up in Wood Lane, who can see on their diagrams what mode their trains are in. The ceiling is 85 kph - 53 mph - post Chancery Lane. It can get pretty choppy up there, but I would doubt that ceiling is being exceeded. As you know, following a software update, Auto cannot exceed 85, but the target speed will get to 100 and the ATP will allow humans to drive that fast, but you would be in serious trouble if you got caught doing that and everybody knows that. There's no good reason for anyone to take that risk. The ATP however will not allow you to get much faster than 100 kph (62 mph). Other giveaways if sitting behind the driver. Starting in ATO the relays always make the same noise when start buttons are pressed. Using the TBC means the relays releasing brakes seem to operate slower. Can sometimes hear the ATP chimes if right behind the driver as well as the overspeed alarm. As tut explains if you are a regular you can be 99% sure if the trains being driven in ATO or CM. However there are some drivers who are bang on the ATO profile. On flat gradients speed is maintained constantly. Well certainly appears to be, none of that one off nonsense as with Seltrac but I'm not sure if that's just because you don't notice it with DC motors as much? On down hill stretches you can see the brake needle shooting up or hear the relays applying then releasing the brakes every two or three seconds. As well as braking for several consecutive downward target speed changes, i.e Liverpool Street westbound. Brakes comes on for the first PSR approaching the station then released just after BMB, couple of seconds then brakes back on for the final speed into the platform. Drivers would tend to brake earlier and coast e.t.c Regarding above 85KPH you can't be sure unless you are at the front! Although there have been a few times where in CM it definitely has felt a lot faster! However some cars have a tendency to sway about a lot more and make more noise so you never know!
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Post by patrickb on Apr 7, 2016 20:48:39 GMT
The present Central Line signalling comes with two aspect and three aspect signals which I presume makes operating in Coded Manual more simple and thus explain why the Central permits Manual running on Sunday's and Bank Holiday's? or could there be an underlying reason? The colour light signals can't really be said to make Coded Manual more simple in themselves, I wouldn't say. They're installed at junctions, where their route indicators are valuable, but that's not really that big a deal. They're installed at stations, where they are definitely a nice feature, because you can glance at a big colour light, but that goes for Auto as well. Then there are the remaining ones in between, which aren't that plentiful. I have read that the main reason for their installation was early suggestions of possibly running non-ATP fitted trains, such as engineers trains, to colour light signals, but that was abandoned. That may just be a rumour, though, and mainly they're useful for trains in RM. The rest of the time, I mean, the light doesn't tell you the target speed. Well, the red light does tell you that the target speed is zero, but the white and green lights do not give you the target speed. Also, the red light may be some distance away when you first see it and there may be a few block marker boards between you and it at which the target speed will be checked down, so it's the in cab display that really matters. The colour lights are presumably a nice thing to aim for, slightly easier to see than a block marker board maybe? I've never driven a Central line train, but it hardly seems plausible that this is a major factor. You could have only block marker boards and it wouldn't make a huge difference to Coded Manual or Auto operation, really. It would make both of them slightly less ergonomic, as I say, the colour lights are great as station starters and handy at junctions, but it wouldn't have a huge effect on how you drive. It'd make RM operation impossible though! What is a major factor is fixed block signalling. Them block marker boards and signals don't move, they're always in the same place, and you have a fixed target to aim at. The target speed drops in managed stages. The target speed and target point aren't constantly updating and changing and moving. The system is also less of a pig and it doesn't enforce its driving style on you as much. It gives you the speed you should be doing and the lineside signage and signals give you the point at which you should be doing that speed and then it leaves you to achieve that goal in your own way. Either way, why isn't this put into practice on other Lines with ATO signalling? As stated above by North End it more or less is. Does the Seltrac Signalling on the Jubilee and Northern Line and in future the SSL obviate the need for Lineside signals? Is it technically feasible to install line side signals? Yes it does obviate the need for lineside signals. Route secure visuals are provided wherever there are points for degraded working, but that's all you need. Lineside signals do not integrate very well into moving block signalling and would be of very little value. They would just be expensive to install and maintain and offer no return. RM hold boards suffice for degraded conditions. Also, partially unrelated to topic (feel free to move this to the correct thread) Could Engineering trains from Ruislip be used on the Pic/Met as well as Central considering that there will be different types of signalling in use? Are these trains operated manually? It depends on the individual train and what equipment it's fitted with. They are operated manually. Thank you tut. I have a preference for the Central Line signalling because of it's Fixed Block like style and colour signals. I always like to observe the WOO signal at Roding Valley when it changes from Red - White/Green just before the doors close. It's kind of a downer that the Northern & Jubilee Lines have no working signals, I guess you could say that it makes the lines kind of soulless? It will be even more sad to see the black bag of death over the SSL signals when they are made redundant. (Except for certain sections as mentioned by @aetearlscourt ). It will also mean that trains without the appropriate Cab equipment like Heritage and/or other vehicles can't operate. Again, I'm not quite sure how it all works, but I assume that for special workings you would needs signals or something equivalent to communicate what's directly ahead. Patrick
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