TBTC Testing

[Ben]

And will they ultimately be the ones taking the responsibility?

[mrfs42]

Jan 16, 2011 0:37:33 GMT tubepassenger said:

From the engineer's perspective, testing can only be as good as the specifications demanded from the software. If the requirement was never defined, there is no test case and therefore no green light to look out for.

Ah; so an engineer is only defined by the parameters of the test case, these days?

I thought that 'engineers' tended to look beyond the data - you know empirical data and all that jazz - within reason the requirement can be defined on the basis of the data gained. I don't believe for one moment that there was no test case - if there were not then there would not have been so much 'test running'

Jan 16, 2011 0:37:33 GMT tubepassenger said:

It seems, the testing, the contractor changes, management changes, are all problems originating from those who make the important decisions.

Either that, or those that remain choose not to be proactive.

[Deleted]

Jan 14, 2011 22:58:10 GMT version3point1 said:

Some of the "engineers" that sit on the test trains week after week during closures have never driven trains, will never drive trains and most probably haven't worked on a station when it has gone tits up in their life. Ever. They just sit there, with a laptop plugged into the train, monitoring numbers and green lights – so long as the computer says everything's okay, it must be okay – who gives a flying hoot about a particular problem a particular driver has pointed out time and time again. He's just a troublemaker, of course!

Jan 16, 2011 2:28:51 GMT mrfs42 said:

Ah; so an engineer is only defined by the parameters of the test case, these days?

Of course, as a passenger of the system, I'm not saying it is good that the person testing the system doesn't appear to care about issues raised by a driver; the extent to which someone cares about the bigger picture is dependent on that person and if there are issues to complain about, why is their computer saying everything is ok and not flagging up those issues? I'm assuming the guy with the laptop is there to just test the software?

Anyway, I hope the existing issues will be ironed out eventually, and that the upgrade of the Northern will go much more smoothly.

[Deleted]

Is the route in ATO yet? Ive been told its driven manually but how come it does the keeping to target speed power on/off thing then?

[Deleted]

Yes, pretty much every train is in ATO between Stratford and Dollis Hill. There will be the odd exception where a train is defective or perhaps a driver has returned to work and needs experience of driving in Protected Manual. The last few days have been less problematic and I'm told that speeds into platforms were faster on Saturday.

[Chris M]

The speed into West Ham eastbound wasn't glacial yesterday (the train was already in the platform at Canning Town when I arrived), but was slightly slower than I remember at Stratford.
The problem was, despite there being a "good service" on the entire line, we sat in West Ham platforms for nearer 5 minutes than 1. The reason given by the t/op was "Congestion between here and Stratford due to significant delays elsewhere on the line."

[Deleted]

West Ham on the east is one of the places you will often get a Hold displayed on the screen. The timetable already allows about five minutes for a journey that could take under two. Since there is virtually no chance of getting a prompt response from the Signaller, it is sometimes tempting to revert to a fallback announcement blaming the delay on some issue much earlier in the day - in the absence of any other explanation!

[commuter]

I can't really say I've noticed a noticeable increase in speed now trains south of Dollis Hill are in ATO. I know trains on the Jubilee always used to approach platforms really slow (especially on the platforms with Peds) but there doesn't seem to be much of a change recently; I don't seem to feel trains approach the platforms at fast speeds like on the Central or Victoria.

Am I imagining things, or will they speed it up soon?

[Deleted]

Jan 16, 2011 17:44:31 GMT commuter said:

I can't really say I've noticed a noticeable increase in speed now trains south of Dollis Hill are in ATO. I know trains on the Jubilee always used to approach platforms really slow (especially on the platforms with Peds) but there doesn't seem to be much of a change recently; I don't seem to feel trains approach the platforms at fast speeds like on the Central or Victoria.

Am I imagining things, or will they speed it up soon?

It's the schedule regulation server and the current timetable, which seems to have WAY too much running time built in. If the trains are early they slow down, if they are late they speed up.

[Deleted]

Jan 16, 2011 17:58:46 GMT @cj said:

Jan 16, 2011 17:44:31 GMT commuter said:

I can't really say I've noticed a noticeable increase in speed now trains south of Dollis Hill are in ATO. I know trains on the Jubilee always used to approach platforms really slow (especially on the platforms with Peds) but there doesn't seem to be much of a change recently; I don't seem to feel trains approach the platforms at fast speeds like on the Central or Victoria.

Am I imagining things, or will they speed it up soon?

It's the schedule regulation server and the current timetable, which seems to have WAY too much running time built in. If the trains are early they slow down, if they are late they speed up.

Which is wholly understandable at this stage in the game. The emphasis must be on integrity and reliability, rather than speed, until the system is proven.

Monitoring the departure boards at various times today – if the TfL website is to be believed, regularity appears to have improved somewhat, with pretty constant 4 minute intervals at most stations, suggesting not only that the system is bedding in, but also that the service is being effectively regulated.

[Deleted]

Whats happening regarding the connection to the Bakerloo at Baker Street? Is tripcock signalling going to kept dormant there until the connection is needed?

[mrfs42]

Jan 16, 2011 17:58:46 GMT @cj said:

It's the schedule regulation server

Where's that then? Is it in one place or distributed?

[Deleted]

As several have pointed out, the timetable has not yet changed - the journey time between stations is pretty much the same and if anything has been increased due to more regulation between stations and less dwell time in platforms.

We have suffered about a week of trains crawling into all platforms at 23mph but can confirm that has changed again this weekend and is relatively fast.

I disagree, incidentally, with the comment that jubilee trains 'always used to approach platforms really slow (especially at PED stations). There are tortoises and hares on every line and it has always been quite easy to come into platforms quickly. I always tended to come in faster at PED stations because of the removal of the risk of somone falling or jumping into the train's path.

Anyway, it's a work in progess but I felt a bit more encouraged after today. Not a whole lot went wrong - there was a 5-minute 'shutdown' to allow a 'soft reset' of the signalling system and a brief suspension West Ham to Stratford but nothing too disruptive overall - certainly not the glut of train-borne defects we've come to expect.

[Deleted]

Jan 16, 2011 21:23:30 GMT mrfs42 said:

Jan 16, 2011 17:58:46 GMT @cj said:

It's the schedule regulation server

Where's that then? Is it in one place or distributed?

Something tells me it's at the main signalling centre; Neasden or Baker Street, can't remember which is such. It's to do with running trains to the timetable; perhaps someone a little more knowledgeable on the matter could give a little more detail.

[edwin]

This scheduling regulation thing, why is it only on the Jubilee and not on the Central/Victoria lines? Surely every train should be going as fast as possible, considering every train has the same top speed... Whats the point of ATO otherwise?

[Chris M]

Well you need to leave something in the bag otherwise you'll never be able to make up for any late running; and the current theory of LU and NR timetabling is to leave lots of recovery time to ensure trains run on time (it matters much more that a train arrives within X minutes of when it was scheduled than it does that journey times are as quick as possible^[1]), which will have an effect.
Probably the main reason though is that the current timetable is written around the capabilities of tripcock running, not ATO, while allowing for the inevitable hiccups and teething troubles that introducing TBTC and ATO brings. When the reliability of all aspects of the system has increased and the technology has bedded in^[2] then I would be very surprised if we don't see a new timetable that takes advantage of it. The Central and Victoria lines are not presently introducing a new system, and are long past this testing phase.

[1]Several threads in the District Line and SSR boards that discuss this, one of the threadfinders will give a link to one or more if they think it necessary.
[2]This could be done in two stages, i.e. take advantage of the technology south/east of West Hampstead before the northern/western end of the line is complete, then upgrade the timetable for that section when it's ready; or wait until the entire line is ready and do it all in one big bang (hopefully not literally!). I do not know which is planned.

[DrOne]

Once in effect the point of ATO is to give faster journey times. Why do people expect this now when a) the whole line is not yet coverted b) live testing of the new system has only just begun and c) there has not yet been a timetable change?

If a faster new timetable were introduced before the new system proved its ability to keep to slack times there would be criticism all round. We're all keen to feel the improvements but a bit of patience and perspicacity wouldn't go amiss.

[Deleted]

Jan 17, 2011 2:09:41 GMT edwin said:

This scheduling regulation thing, why is it only on the Jubilee and not on the Central/Victoria lines? Surely every train should be going as fast as possible, considering every train has the same top speed... Whats the point of ATO otherwise?

The Central/Victoria lines have antiquated signalling systems and hence do not have anything of sorts. The idea is to keep trains to a timetable, rather than just gunning it.

[Deleted]

The Schedule Regulation Servers (2 of them) are the bit of the central control system at Neasden that deal with the timetable and in effect request the signalling to route trains (in the TBTC way of doing it). It controls the pace of the trains to meet the timetable and also spaces out the trains across the line so you *in theory* don't get any bunching up. So to do this it delibrately slows down some to space them out. Its all about even distribution and energy efficiency, not just banging them through as quickly as possbile. That being said, when the north end of the line is ready I believe we will see more like Central Line performance typically with more trains out and much reduced journey times.

The Central Line also has the equivalent control centre computer, called "ATR" or something, but I don't think it ever gets switched on and used, as the general control centre does a pretty reasonable job anyway. Its not that old - only late 90's !!

Vic line is old, but is being replaced as we speak, but again until the rest of the line is resignalled, I don't think you will see any difference there either like the Jubilee.

[Tom]

Jan 17, 2011 16:42:43 GMT @cj said:

The Central/Victoria lines have antiquated signalling systems and hence do not have anything of sorts.

I wouldn't call 1991-2001 vintage antiquated (or else I'm way over the hill, despite being quite young by LU standards)!

[mrfs42]

Jan 17, 2011 18:43:47 GMT @sw206 said:

, as the general control centre does a pretty reasonable job anyway.

Local site timetable updates from basic, per site - each station IIRC (well, that's what I remember of a v. drunken conversation with a Westinghouse bod.).

[Deleted]

Jan 17, 2011 19:18:46 GMT Tom said:

Jan 17, 2011 16:42:43 GMT @cj said:

The Central/Victoria lines have antiquated signalling systems and hence do not have anything of sorts.

I wouldn't call 1991-2001 vintage antiquated (or else I'm way over the hill, despite being quite young by LU standards)!

In terms of ATO systems, it is rather antiquated! Bear in mind that it is fixed block.

[Deleted]

Jan 17, 2011 19:28:06 GMT @cj said:

In terms of ATO systems, it is rather antiquated! Bear in mind that it is fixed block.

Under the orignal PPP contracts Metronet decided to use Distance to go ATO rather than TBTC. This decision would have been made around the same time Tube Lines decided to go with TBTC. If it really was antiquated then TBTC would have been the obvious choice for all lines from the start.

[Deleted]

Isn't distance to go signalling near enough moving block?

[mrfs42]

Jan 17, 2011 19:52:38 GMT @cj said:

Isn't distance to go signalling near enough moving block?

No; if anything it is an adjunct system.

AIUI [1] It is a fine and subtle difference, but it isn't quite moving block.

[1] drunken conversation with westinghouse bloke ibid.

[version3point1]

Jan 15, 2011 23:04:42 GMT messiah said:

Still it will be nice when the new system is up and running, and we can all get on a tube at Canada Water without waiting for 3 to go past, absolutely packed (and the tubes at Canada Water in rush hour are as busy as anywhere - there literally is no space to squeeze anyone in at many of the doors as they were packed at London Bridge, and filled more at Bermondsey). This is particularly a problem now with all the Overground passangers coming.

(Sorry for going a bit off topic from the thread, mods/gods...) Unfortunately, I think we all know the Tube is operating to what essentially is maximum capacity. When Woolwich Arsenal DLR opened, people assumed that North Greenwich would become less busy because it was assumed that the masses that took the bus to Woolwich would now take the DLR – how wrong the assumptions were! The buses are now as busy as they were, North Greenwich is far busier than it was and Canning Town has been thrown into that mix as well. I agree with you about Canada Water (having worked there once) – it has become a major hub now, along with a few other what-used-to-be-quiet stations on the Jubilee line extension. With South Eastern being as unreliable as anything these days, we're finding more and more people getting on at London Bridge anyway, and with the Westbound trains equally as rammed from Stratford in the mornings, it's as if nobody seems to work anywhere now apart from Canary Wharf (it's like mass exodus there on a normal day). I'm not holding my breath to see whether Crossrail takes away some of the strain from everyone's journey...

Jan 16, 2011 23:00:21 GMT @tubbytube said:

We have suffered about a week of trains crawling into all platforms at 23mph but can confirm that has changed again this weekend and is relatively fast.

I disagree, incidentally, with the comment that jubilee trains 'always used to approach platforms really slow (especially at PED stations). There are tortoises and hares on every line and it has always been quite easy to come into platforms quickly. I always tended to come in faster at PED stations because of the removal of the risk of somone falling or jumping into the train's path.

Anyway, it's a work in progess but I felt a bit more encouraged after today. Not a whole lot went wrong - there was a 5-minute 'shutdown' to allow a 'soft reset' of the signalling system and a brief suspension West Ham to Stratford but nothing too disruptive overall - certainly not the glut of train-borne defects we've come to expect.

Agreed. Agreed. Agreed.

Having just come back from three weeks of leave and thus missing most of the TBTC 'action' since implementation, I am reasonably impressed that it's not so much of a mess-up now as it was every other time I've worked during TBTC running. Working the evening peak tonight, I was relatively surprised at how one train would depart, and literally 25 seconds later (and yes – I counted using the dot matrix timers) another train had already fully berthed the platform and opened its doors. This happened with three consecutive trains.

I was also surprised on Sunday night, given the system reboot, that we managed to pick up the pace fairly quickly, and by the time The O2 were kicking out the little darlings from the JLS concert, we had a regular-and-to-the-minute 3 minute service on the westbound (yes - the eastbound was a bit ropey, but you can't have it all). 16,000 cleared in under 45 minutes is a record (with the worst part of the evening lasting about 15 minutes – again record, considering 17,000 takes about 1hr to clear, worst part lasting about 25-30 minutes, alcohol dependent).

I too am feeling a little bit encouraged, though to get to a stage like this has taken far too long. There's also several things that worry me – we had a situation with the PEDs some time ago, whereby a door had to be isolated, but the train had no forward movement. Whilst this has been fully investigated and the root cause found, nobody has decided to enlighten us (or anybody else with PEDs for that matter) about what the actual problem was, what caused it and how to prevent it happening in the future. Somebody has also been told (by a duty manager trains) that "you can't isolate a door unless the door is fully closed." Well – what a sweeping statement. Under tripcock operation, if a door was failing to close, failing to open or just any general fault occurring that prevented the PED suite from being proved closed, you could isolate that door. We will always try to ensure the door is shut before isolating (obviously to prevent somebody falling onto the track), but usually, if there's an obstruction that is fully preventing that door from being shut, we would still isolate that door and have a barrier (or the member of staff who has isolated the door) standing in front so that there is no risk to those passing by when the train approaches/departs. Nobody has really explained the whole PED situation at all and I'm now fairly reluctant to even touch the things should it "close the track" (as they're now "in" with the system)... I have chased it up, but I might as well have sent in a Stamped Addressed Envelope...

[Deleted]

All I can say is that I'm glad I'm a shift worker and don't have to travel in the rush hour unless it's after a night shift but even then I'm traveling against the tidal flow. I think I'd get suicidal at the thought of having to put up with the crowds every day.

[chorleywood]

Jan 17, 2011 18:43:47 GMT @sw206 said:

The Schedule Regulation Servers (2 of them) are the bit of the central control system at Neasden that deal with the timetable and in effect request the signalling to route trains (in the TBTC way of doing it). It controls the pace of the trains to meet the timetable and also spaces out the trains across the line so you *in theory* don't get any bunching up.

The Central Line also has the equivalent control centre computer, called "ATR" or something, but I don't think it ever gets switched on and used, as the general control centre does a pretty reasonable job anyway. Its not that old - only late 90's !!

Yes - the central line has an ATR subsystem which isn't enabled as it tended to show up issues with both the underlying ATS (Automatic Train Supervision) system and also the cab displays which were designed to give "time to depart" at each station (who remembers "spurious "hold" indications?)

Bizarrely, parts of the Piccadilly line have (had?) an early form of Automatic Train Regulation, which was effectively a simply analogue computer. From distant memories of bookwirings, this used a pair of wires running between stations, an arrangement to switch resistors across these wires dependent on train positions, and a comparator unit at some stations which would hold trains dependent on the relative resistance across the pairs of wires ahead and in rear of the station. A "Balance Headways" switch in the control room enabled the system. Does anyone know if this system is still in use?

[Deleted]

Jan 16, 2011 20:16:34 GMT @bronzeonion said:

Whats happening regarding the connection to the Bakerloo at Baker Street? Is tripcock signalling going to kept dormant there until the connection is needed?

An interface to the Bakerloo line signalling has been included in the Jubilee line TBTC system at Baker St. Trains running onto the Bakerloo will normally have tripcocks and trains running onto the Jub will normally be TBTC equipped.

[Deleted]

@ ta

Thanks for telling me!, I was going to start a new thread about this because no one had answered it! What if 1972 stock trains need to get off the Bakerloo?