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Post by Tubeboy on Jan 5, 2011 2:39:20 GMT
That train at 1639 hrs wasn't gapped. It was non communicating TBTC wise. Had trouble as soon as it left Stratford. Put into RM mode and worked to West Ham and taken out of service. Some Eastbounds were reversed at NOG to cover the gap.
For the evening peak 41/50 trains were in service.
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Post by Deleted on Jan 5, 2011 8:40:00 GMT
Ah ok, thanks. Apologies. I should have said 'stalled' rather than 'gapped' - as usual some 'Chinese whispers' going on - didn't mean to add to that. Was puzzled about that because more than once Line Controller talked about train stalled on Eastbound between West Ham and Stratford and I was wondering how (and why) on earth it had reversed back Westbound!! I'm glad I'm not the only one who gets west and east muddled up (complicated by the fact that West Ham is geographically slightly east of Stratford).
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Post by Deleted on Jan 5, 2011 13:34:07 GMT
Evening peak seems to have gone OK - were there a few trains less than normal though? Seemed to be a few odd gaps here and there, but otherwise not bad considering its first day of peak loadings. Here in the offices at Canary Wharf I would say there are still only about 50-75% of the normal people in - school holidays still in progress, many have taken annual leave, and foreign visitors not around. The poor souls who commute in on the Jubilee, from both Stratford and Waterloo directions, say yesterday was chaos both morning and evening, and were most unimpressed to learn that this is the New World, and certainly not "not bad". Today the Essex lot who come in by Stratford have moved across bodily to the DLR (and apparently overloaded that), as being more likely to get them in. The thing that we, being mere mortals from a different technological world, cannot understand, is why the various issues being discussed here were somehow not discovered at some stage in the last several years of installation and testing - and how many more remain to be discovered. |
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Post by Deleted on Jan 5, 2011 14:21:15 GMT
it certainly does seem odd compared to that different technological world (i.e. investment banking IT) where small iterative changes are generally preferred to big bang changes that transport professionals who have to keep the service running for 20x7 days choose the big bang approach. Whoever it was that signed off the big bang change should have his/her head examined!
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Post by Deleted on Jan 5, 2011 16:22:37 GMT
To the Jubilee's credit, it was running well this morning as far as this mere mortal is concerned  |
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Post by Deleted on Jan 5, 2011 16:52:42 GMT
I've been checking the TfL website on and off all day and I have no issues to report either!
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Post by Deleted on Jan 5, 2011 19:26:07 GMT
Evening peak seems to have gone OK - were there a few trains less than normal though? Seemed to be a few odd gaps here and there, but otherwise not bad considering its first day of peak loadings. The thing that we, being mere mortals from a different technological world, cannot understand, is why the various issues being discussed here were somehow not discovered at some stage in the last several years of installation and testing - and how many more remain to be discovered. On the other hand, bankers do expect to be paid very high bonuses but not to pay the price for their actions when they misjudge the market in a string of corporate and individual screw-ups. How many more bad debts have yet to be discovered and to be written off by banks? How many more billions of pounds will tax payers underwrite? Having said that, I'm not anti-finance. I am just a realist and understand that not everything goes according to plan whether that be in correcting a recession and getting the economy functioning with a good debt to equity ratio or implementing a new signally system on a Tube line. It all takes time, effort, some errors, correction of those errors and a bit of luck. That's from the perspective of a mere mortal who works in The City but not in finance.  |
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Tom
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Post by Tom on Jan 5, 2011 21:58:04 GMT
The thing that we, being mere mortals from a different technological world, cannot understand, is why the various issues being discussed here were somehow not discovered at some stage in the last several years of installation and testing - and how many more remain to be discovered. Sorry to disappoint you, but Signalling Engineers are only human too. The more towards a 'black box' system we go, the harder it is to predict how the system will behave under every possible permutation, and the harder it is to test - which is one of the advantages of a more traditional system, albiet things can still slip through the net and go undiscovered for many years! At least with a traditional system one can set up conditions and clearly see the effect at each stage, wheras with this you have to rely a lot more on the data validation and end results. It's got to be at a stage where it can be trusted to perform, or else it wouldn't have been commissioned - but I wouldn't be surprised if some of the quirks of the system are still to be discovered in the next few weeks and months. |
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Post by Deleted on Jan 5, 2011 22:29:35 GMT
On the other hand, bankers do expect to be paid very high bonuses but not to pay the price for their actions when they misjudge the market in a string of corporate and individual screw-ups. How many more bad debts have yet to be discovered and to be written off by banks? How many more billions of pounds will tax payers underwrite? Having said that, I'm not anti-finance. I am just a realist and understand that not everything goes according to plan whether that be in correcting a recession and getting the economy functioning with a good debt to equity ratio or implementing a new signally system on a Tube line. It all takes time, effort, some errors, correction of those errors and a bit of luck. That's from the perspective of a mere mortal who works in The City but not in finance. Sorry, but don't judge everyone that works in finance with the same brush. I work in financial IT and have absolutely nothing to do with the business decisions (good or bad) to which you refer. However, in the environment, we do learn how to make changes to systems and build infrastructure without taking on some questionable risks (technological you understand) Anyway, I don't think this is a subject worth discussing. I'd rather find out about the TBTC and ATO if that's ok |
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Post by edwin on Jan 6, 2011 1:15:22 GMT
Went on the Jubilee line from Westminster to Kilburn today. Certainly feeled a lot faster, no complaints from me.
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Post by Deleted on Jan 6, 2011 6:00:14 GMT
Remember that at the moment the new system is only trying to match what was previously delivered - WTT10, so we won't be seeing much difference in performance as the trains will be regulated to match that, not running flat out to fit in loads of more trains.
I think it appears that at the moment, although it is running fairly well considering its only just been switched on, there does seem to be a struggle to get a full fleet of trains operational.
Are there any plans to change the timetable before the north end is complete and Stanmore 3rd platform is opened? I wonder if some additional trains could run in a few weeks when it has settled down and trains are available before the north end is resignalled?
As for catching DLR instead into Canary Wharf, hmmm, a choice of TBTC or TBTC to travel on there! I suppose the software is more mature on that line though.
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Post by Deleted on Jan 6, 2011 11:48:59 GMT
I have to say, the change in speed is really significant for me. I was getting used to dawdling and an hour commute taking at least an extra 15 mins before Christmas! I made it in just under an hour today, which hasn't happened in a long time!
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Post by Deleted on Jan 6, 2011 12:57:15 GMT
As for catching DLR instead into Canary Wharf, hmmm, a choice of TBTC or TBTC to travel on there! I suppose the software is more mature on that line though. What do you mean by "the software is more mature on that line"? I thought part of the difficulties, as explained by someone earlier, were caused by implementing the system in a different environment which produced new problems not experienced before during the DLR implementation. Surely, when they started on the Jubilee upgrade, the software would be based on the latest version that was in use on the DLR? Rather than rewriting everything? I wonder, if relevant software changes made to the Jubilee TBTC system would also be used to update the working DLR system?? |
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Post by metman on Jan 6, 2011 17:12:02 GMT
Help! I have no idea what's happening on the Jubilee Line. All the signals are covered up! I'm a traditional block man so somebody needs to explain what all this TBTC is about....
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Post by londonstuff on Jan 6, 2011 17:18:06 GMT
I went from Westminster to London Bridge and then from LB to Bond Street. On those sections it was a bit faster, maybe, but not much in it. I also noticed the regular braking, which I'm sure doesn't do the motors any good.
A few questions:
Can the software be modified to give a more consistent target speed rather than start, stop, or is that just the nature of the beast?
Are there going to be more trains in service when it's all fully up and running or are they just going to use the ones they've got to get there more quickly?
No platform repeaters - where are the indicators of target speed given for CSA's, etc.
Loads of questions about this, really intrigues me!
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Post by c3c on Jan 6, 2011 17:28:07 GMT
I have notice quite a long delay at dollis hill in both directions. I guess this is because of the swiching to tbtc.
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Post by norbitonflyer on Jan 6, 2011 17:52:21 GMT
Help! I have no idea what's happening on the Jubilee Line. All the signals are covered up! I'm a traditional block man so somebody needs to explain what all this TBTC is about.... I didn't know either, but Googling, and reading the relevant threads on here, I understand TBTC (when it's not a Transportable Blood Transshipment Center or Tributyl Tin Chloride) is "transmission based train control". Each train transmits its position and other data to a control centre which then relays that information to the following train, allowing the second train's speed to be controlled to maintain a safe separation between them. Is that more or less it? How does it differ from the 1967-vintage system used on the Victoria Line? |
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Post by jmm on Jan 6, 2011 17:52:21 GMT
What will happen in the case of a problem with the TBTC system? Will they remove the old signalling after a few months or years?
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Post by 21146 on Jan 6, 2011 18:16:14 GMT
The "1967-vintage system used on the Victoria Line" works better.
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Post by Deleted on Jan 6, 2011 18:32:58 GMT
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Post by Deleted on Jan 6, 2011 18:40:42 GMT
Help! I have no idea what's happening on the Jubilee Line. All the signals are covered up! I'm a traditional block man so somebody needs to explain what all this TBTC is about.... I didn't know either, but Googling, and reading the relevant threads on here, I understand TBTC (when it's not a Transportable Blood Transshipment Center or Tributyl Tin Chloride) is "transmission based train control". Each train transmits its position and other data to a control centre which then relays that information to the following train, allowing the second train's speed to be controlled to maintain a safe separation between them. Is that more or less it? How does it differ from the 1967-vintage system used on the Victoria Line? The Victoria Line original system differs a lot. It uses fixed coded track circuits, the codes obviously for ATO but double up as the track circuits. The codes in the rails are the safety box codes. This controls things like top speed, and whether motoring is allowed. This is the failsafe element. Signal brake and station brake is on the auto driver box- this drives up to a given speed from the safety box. Being the not failsafe part, the signalling is designed to be failsafe, with overlaps and such based on the auto safety box codes. The central line signalling is basically a much more advanced version of this with shorter track circuits, PAC giving a fair chunk of data to the train, and a lot more target speeds. As the target speed also contains the next track target speed it can be used for manual driving under ATP, unlike the Vic signalling where the first thing you'd know about a 180 code in manual would be the train line dumping and some lovely wheelflats after. TBTC has no fixed track circuits, and finds where the trains are to allow them to come very close together and set a perfectly variable target speed. |
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Post by Deleted on Jan 6, 2011 20:02:03 GMT
After a couple days' use in the peaks my impression is that the end-to-end journey times are much faster, but that'll be mainly down to the increased capacity allowing full speed to be attained, whereas the rather long blocks resulting from hasty reversion to conventional signalling following the (allegedly) failed Westinghouse system planned for the Extension in 1999 resulted in peak congestion, particularly a.m.
That said, at present the number of trains seems to be considerably short of the maximum – roughly 3-4 minute intervals rather than 2½ previously – although indications are the system will be well able to cope.
However, I did observe notably faster running from St John's Wood down to Baker Street, complete with the pressure wave I haven't perceived in ages.
One downside though – the closure between Stanmore and West Hampstead this Sunday appears to be the last scheduled in the TfL works programme, so if this really is the last then it's farewell to Met trains stopping at Willesden Green, and this may perhaps be the only occasion when S-stock trains call there! Also farewell to a motley variety of vintage buses, including RMs and RMLs, on Jubbly replacements.
Every silver lining has a cloud.
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Post by Deleted on Jan 6, 2011 21:19:52 GMT
It might be the last published closure, but it can't be the last one - there is a lot more work to do from what I hear to finish off the north end of the line.
When I mentioned software is 'mature' on DLR, I was referring to the fact all the train software is different, the onboard computers are newer on the Jub and although similar, have different processors in. The control centre software is obviously different as the geophical map of the railway is poles apart. Plus Jub has PEDs, route secure indicators, platform depart indicators, digital train operators displays (DLR is analogue), Jub has digital axle counters whereas DLR has older ones. The list is endless and the software is only similar in the fact the end product produces a similar concept. Therefore each implementation of TBTC takes months of software development and testing.
There were a few trains missing again today - I expect this will continue for a while, but as said ATO and speed increases seems to compensate to give an acceptable service. I believe there will be up to 55 or more trains in service eventually rather than the 47 or so typically used today out of a total of 63.
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Post by Deleted on Jan 7, 2011 0:19:29 GMT
My experience of the last couple of afternoons/evenings has been that I've reached every terminus, meal relief and bookoff point on time or a tad early. I'm not sure that's ever happened to me before on successive days! That is good for everyone.
I must say I find the actual movement of the trains annoying bordering on embarrassing at times. I don't want to appear too precious about driving technique because many passengers probably don't care too much about the lack of a smooth ride. But I would also like to know if there is a way of preventing the 'thermostat' stop-start as the train tries to keep at a target speed. It is particularly jarring when the speed is slow - and the speed is very slow at times as you are effectively being regulated in section rather than in the platform. It's not a bad thing to avoid long platform dwell times but I don't think they've quite got the balance right.
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Post by Tom on Jan 7, 2011 9:15:38 GMT
The central line signalling is basically a much more advanced version of this with shorter track circuits, PAC giving a fair chunk of data to the train, and a lot more target speeds. Are you sure? Have you seen how short a Victoria Line track circuit can be - three track circuits per platform is fairly common, with lengths of around 120' not unheard of. In contrast, the Central line generally has around two track circuits per platform, but they can be longer as there are more codes available. |
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Post by 21146 on Jan 7, 2011 10:48:25 GMT
Why are these trains stopping with a pronounced 'jolt' at each station, as if the T/Op had released the 'deadman' too early? It doesn't happen on the Victoria Line, Central Line or DLR? That's why I said the Vic's old system works better.
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Post by Deleted on Jan 7, 2011 11:01:37 GMT
Surely the Jubilee has to be that bit more accurate with the stoppng, because of the PEDs? Does this affect the way the braking operates?
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Post by Deleted on Jan 7, 2011 16:07:21 GMT
The jolt can be removed, as in careful car driving, by releasing the brake the millisecond before stasis and then reapplying it once stationary. Perhaps the software can be tweaked to achieve this. Also, the "thermostat" de-accelerate effect is distinctly noticeable to passengers and I hope the software can also be tweaked to alleviate this.
Are all trains using ATO now? All the ones I've travelled on this week appeared to be. Also the service seems to be achieving good regularity now, roughly 3-4 minutes, implying consistent driving.
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Post by Deleted on Jan 7, 2011 19:19:18 GMT
Oh dear, spoke too soon! Disaster has struck again with a failure a Waterloo and the line once more divided in two. And the Waterloo and City suspended due to overcrowding!
What a fiasco.
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Post by Deleted on Jan 7, 2011 19:44:46 GMT
Western part works rather well though...
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