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Post by Tom on May 19, 2020 17:19:21 GMT
Our management don't judge the service by how many passengers we carry, they rate it by the number of miles the trains travel. They'll report that we're running a 70% service without worrying whether the service level is too much or too little for demand. Agreed, but that's (at least currently) because one of the government's requirements for the funding agreement is a return to pre-Covid service levels.
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Post by Tom on May 17, 2020 14:12:51 GMT
I think Test Train Operators did most, if not all(?) of the 'Off line' driving - I certainly remember asking a favour of one of them to take it slowly through Sudbury Town, where I'd left the tour to get a couple of lineside shots.
One of the less than friendly supervisors was on duty at Ealing Broadway later that day, and was about to throw all the waiting enthusiasts off the station when the tour train arrived - I seem to remember the Victoria Line General Manager overruling him in that respect!
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Post by Tom on May 15, 2020 20:50:52 GMT
That makes sense, then why not film something at Churston, Kingswear or Dartmouth in the trailer? The use of Paignton just seems wrong if you're trying to draw someone in to watch a programme about stunning railway architecture.
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Post by Tom on May 14, 2020 19:48:04 GMT
I'm not surprised - the number of lights that are out on the average 72 Stock car has just been decreased!
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Post by Tom on May 14, 2020 19:21:05 GMT
Sit on the Board, or attend Board Meetings? The two are very different.
I think a fare rise is guaranteed, what will be interesting is what else comes as part of the review of TfL's finances. Personally whilst I think the Government might welcome Night Tube returning it was always used to sweeten the bitter pill of ticket office closures and there will be no 'sacred cows' when it comes to cost-cutting, especially if it is running at a loss.
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Post by Tom on May 12, 2020 22:36:35 GMT
Other visible differences: Detail
| 1972 Mark 1
| 1972 Mark 2
| Moquette
| Grey | Blue
| Doors
| Unpainted | Red | Fleet name
| UNDERGROUND | Solid red roundel
| Train Number Plates
| Centre of M Door
| Offside window
| Cab front
| No handrails
| Handrails and step plates
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I'm sure there were other differences in the cab, but these are the ones that would be obvious from the outside. Others please feel free to add!
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Post by Tom on May 12, 2020 19:31:29 GMT
They did indeed, 1977-1979.
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Post by Tom on May 12, 2020 18:14:28 GMT
Both versions were crew operated when introduced.
The story of the 1972 stock goes back to 1969, when a long-term dispute at Acton Works caused a shortage of air compressors for 1938 stock. This caused serious issues for the Northern line with up to 40 trains each day cancelled and a number of trains short formed with 6 cars rather than seven. Horace Cutler (later to become leader of the GLC) took a rush-hour trip on the line in May 1970 to see how bad it was for himself, and on his return to County Hall there was a bit of an uproar. This resulted in LT ordering 30 trains of 1972 (Mark 1) Stock in July 1970. Due to the urgency of the order a number of features from 1967 stock were retained, including the lack of side doors to the cab.
However, there was then a problem at Metro-Cammell as there was no work available for them from the end of the 1972 Stock order and the start of manufacture of 1973 Stock, which was going to be a bit longer based on the fact that they were of a new design. To keep Metro-Cammell afloat LT then ordered a further 33 trains of 1972 Mark 2 stock, the idea being that they would go immediately to the Northern line to allow some 1938 Stock to be scrapped before the 1956/59 Stock was available, which would happen when they were displaced from the Piccadilly by the 1973 Stock.
It also meant that they could supply the Jubilee line with it's own new(ish) fleet when it opened in 1977 (as planned), as by then enough 1973 Stock would be available to free up the last of the 1959s on the Piccadilly, and then when the Jubilee line gained its own purpose built fleet (which was then supposed to be 1978 Tube Stock, but eventually arrived as 1983 Stock) they could go to the Bakerloo giving it a modern fleet to replace 1938 stock there.
As Jackson and Croome wrote: Who could resist spending a little more public money to achieve such eminently desirable ends?
What actually happened was that 1983 Stock displaced 1972 Mark 2 stock back to the Northern line and 1959 stock from the Northern to the Bakerloo enabling the elimination of 1938 Stock from the Bakerloo... but then the desire came to convert the Bakerloo line to One Person Operation (no doubt assuming that this would be achievable without new trains, unlike on the Northern line). This meant that the 1959s on the Bakerloo were swapped with 1972 Mark 2 stock, which were then converted for OPO.
For the rest of the story I would recommend the February 2020 edition of Underground News, which gives more detail of what went where and when.
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Post by Tom on May 12, 2020 11:00:48 GMT
Original post edited as I'd said the same thing as countryman, at exactly the same time, it seems. But we're straying off topic now...
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Post by Tom on May 11, 2020 19:53:42 GMT
Was the peak of a shorter duration this morning? I can see it was crowded at all the usual hotspots (Canning Town for example) but was it the full 0600-0945 affair or was it all over by, say 0800?
As for the requirements, taking into account the latest statement from Government, the advice appears to be "Don't go to work unless you have to go to work, in which case don't use public transport, but if you have to, observe social distancing. Unless you can't, in which case wear a mask." Is that about right?
Personally the only trains I've seen since March 17th have been the Windsor branch shuttles at the bottom of my garden, and I don't expect this to change for the foreseeable future.
(Fellow mods - please feel free to smack me down if I've strayed over the boundaries into politics!)
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Post by Tom on May 10, 2020 17:48:42 GMT
aslefshrugged, you've made your point previously and it was noted then. If you have nothing to add to the conversation please feel free not to post in it. If you have something to add, play the ball and not the man as the saying goes.
Post (and subsequent post by londoner because it didn't make sense without context) moved to Deleted Threads.
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Post by Tom on May 10, 2020 17:35:44 GMT
I've not seen any of them but the trailer features an opening clip from Paignton (Queen's Park) station. The building is of little architectural merit and is a hideous 1970s asbestos sheet construction dressed up. The thought that it was used for series celebrating railway architecture makes me shudder.
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Post by Tom on May 9, 2020 22:14:52 GMT
Handling London's Underground Traffic by J.P. Thomas, if you can get your hands on it, is well worth a read. It's fast approaching a hundred years old, but has stood the test of time. Much of LU's current management would benefit from a copy.
Other more recent (but still long out of print) are P.E. Garbutt's How the Underground Works and H.G. Follenfant's Reconstructing London's Underground.
Personally I would disagree on Glover's edition of London's Underground - like many Ian Allen (sic) publications it would benefit from a decent proofreader's attention and Glover is somewhat out of date in what he describes. I seem to remember one edition was reviewed rather unfavourably in Underground News.
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Post by Tom on May 8, 2020 12:16:11 GMT
Ah yes, the 'other' FIS!
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Post by Tom on May 8, 2020 12:14:23 GMT
Keep it on topic please. Whilst public services are always a political hot topic, this thread (and this forum) isn't about politics.
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Post by Tom on May 7, 2020 22:19:30 GMT
As far as I'm aware none of the TOps off at the moment have been "furloughed" as they would have to be "unfurloughed" (is that a word?), creating unnecessary delays before they could return to work I thought Train Operators and other operational staff who were shielding for twelve weeks have been furloughed? Apparently once someone has been initially fuloughed they have to remain off for the minimum three weeks, however after three weeks they can be recalled to work at short notice, possibly 24 hours. Naturally this may not necessarily work for Train Operators.
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Post by Tom on May 7, 2020 22:15:32 GMT
And now that we go to Wimbledon I'm able to make some kind of comparison with the west end of the line. I left Wimbledon around 7.30am and it was dead as a Dodo. I picked up about 30 people between Wimbledon Park and Earls Court - and that was with a ten minute road as I know what time the train in front of me left Wimbledon. The contrast with the east end of the line couldn't be more stark! I wonder if that's a reflection of the social demographic in the area - with Wimbledon being generally ABC1 (solidly middle-class, office jobs, able to work from home or travel by car) and the East End being C2DE (working class, manual workers, reliant on public transport) - with the notable exception that Upminster is probably more ABC1 than C2DE?
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Post by Tom on May 5, 2020 20:11:27 GMT
I have to admit I sought confirmation from Google Maps and it didn't just support my answer but confirmed it rather categorically!
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Post by Tom on May 5, 2020 19:15:12 GMT
Yes, though technically it shouldn't be possessive.
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Post by Tom on May 4, 2020 23:07:46 GMT
And it was ever thus!
It's easier than saying 'number 18 lever' - though I would never write it like that in anything official - it would always be No. 18 lever or Lever no. 18.
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Post by Tom on May 4, 2020 21:05:15 GMT
I was heavily involved, yes.
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Post by Tom on May 4, 2020 19:12:36 GMT
So, what about mechanical locking? Well, conveniently I'm pretty well placed to answer that one, having tested all the mechanical locking alterations undertaken by LU in the last five years.
One frame was completely relocked from scratch and I did the majority of the testing for that off site, on a frame used only for testing purposes. Beforehand, in a similar manner to circuit logic, you sit and review the mechanical locking arrangements. Usually this involves working out in your head what the locking should be, and comparing that to the version in the design, then trying to understand and justify the differences between your solution and theirs.
When you go to the test frame, you check the mechanical locking is correct to the dog chart (the drawing which shows the positions of all the locking pieces) and then try to move each lever in turn. It should only move with the pre-conditions (known as the lever leads) required for it to be able to move met. For instance, let's say that No. 19 lever can only move if no. 18 lever is reversed. Can 19's move with 18's normal? Can 19's move if 18's is mid-way between normal and reverse? It should only move when 18's lever is fully reversed. (Repeat for all over levers) Once 19's lever is reversed, it should lock 18's reverse. Does it? When is the locking removed? It should only unlock 18's lever when 19's is fully normal.
Another example is that 16's lever reverse locks 18's lever normal. Does it? If 16's is reverse, Does it lock other levers unnecessarily - can I still move levers 13, 14, 16, and 20 freely?
Once I was satisfied, the locking is disassembled and taken to site. When it was refitted, I went through a simplified testing routine to make sure everything still locked correctly according to the locking table - this took about 20 minutes on a small frame.
The majority of alterations I have been involved with have been mods to existing locking. It's a bit different as you review the locking arrangements but don't test the lever leads too widely - you take those as given, and if they're wrong they tend to be fairly self-announcing.
When it's an alteration, you're there watching over the locking technicians as they alter the locking in many cases, so you know exactly what locking pieces are being removed and installed. Next, I take out all the fuses to the outside world (so I can't accidentally throw points) and disconnect the electric locks, so that I know I'm not having any mechanical locking masked by electrical locking. (This doesn't stop you from being masked by other pieces of mechanical locking though - more on that later.) When it's all in, I tend to test the alteration first to make sure it works, then get the locking tech to secure the screws holding the locking pieces in place. Then, check it all corresponds to the locking table - which on a bigger frame can need two people and take several hours - Uxbridge takes about three hours and there is a lot of masking where you can't see a lock because of another lock doing the same thing. The only way to get around that is to take the other pieces of locking away - which isn't advised, so I have to use another alternative method, which is the comparison against the dog chart to confirm that the locking is there, even though I can't prove the locks are physically interacting.
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Post by Tom on May 4, 2020 18:51:04 GMT
Absolutely. Capacitor fed track circuits on average take about 20 minutes per track, FS2550 take about an hour per track.
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Post by Tom on May 4, 2020 18:30:18 GMT
It depends a lot on whether or not you have a new interlocking, or it's an alteration to an existing one. Generally on an existing interlocking you spend more time proving the presence of correct functionality associated with the change, rather than absence of unintended functionality (though I have been known on occasion to do some negative testing, as time permits). Prior to the commissioning the Principles Tester will undertake a thorough review of the design and the signalling being introduced. Does it comply with all the standards? Has the designer omitted something? Are there unusual conditions which need to be accounted for? Are there any logic conditions 'masked' by the operation of other conditions, and how will I separate them out to prove each one? This review period often includes a period of to and fro discussion between the tester and the designer. When testing a new installation we would undertake what's known as 'flood' testing as an initial test. Flooding means drop every track circuit, break the detection on every set of points, etc, so that none of the interlocking's inputs are present. This is ideally done without the interlocking connected to the railway, but instead to a test desk, but beware, this is what they used when the train derailed at Waterloo, so you have to be careful. Here's an example of a test desk, used at King's Cross back in 2015: This was a relatively small interlocking, and there were still 66 function inputs to be simulated. Imagine doing that with a site like Acton Town! With the test desk connected, try and clear a signal. Nothing should happen. Introduce each condition you need in turn, until you have all the conditions you need to clear that signal. If the signal clears when it should with all other conditions broken, you have proved the absence of unintended functionality for that signal to clear. You then repeat it for all other signals, then do the same with their approach and back locking, etc. Usually at this point, you'd take the test desk away and connect the interlocking to the railway. Does each track circuit/point/signal/trainstop correspond correctly to the interlocking? If it does, read on... Once you get more and more proof of the correct functionality on a signal by signal basis, you move to more dynamic testing. Can I do parallel moves? Does a second train approaching a signal before a junction prevent the previous route from correctly unlocking? Can I lock a junction up with a single fault? Does a route unlock prematurely? From then, it's more akin to 'playing trains' - you simulate train moves, try combinations of things, how close you can get trains etc. After that - connect up the control system (which may or may not have been tested as an integral part of the vital signalling), and check there are no race conditions or response delays. Finally, bring in test trains. These are your final tests, and are used to double check that real-life operational response times don't have any untoward effect.
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Post by Tom on May 4, 2020 15:07:11 GMT
Hope good products and good installation get selected. Come on - how long have you been here now?
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Post by Tom on May 4, 2020 15:06:12 GMT
Typical. I forget to check in on a thread and all sorts of interesting stuff gets discussed! The current plan is for a straight 33 1/3 to 125Hz conversion of relevant circuits on the Rayners Lane branch, which would basically be limited to track circuits and signal selection (control) circuits. It would be implemented in much the same way as was done on the Bromley-by-Bow to Upney(?) section of the District line, with new feed kiosks and changing of relays as required. Personally, I think a straightforward signal main conversion would have been easier and more effective (there are issues where you mix 33 1/3 and 125Hz supplies on the same piece of kit), but there was a reluctance to install new 125Hz frequency converters in the substations. @aetearlscourt is quite right that there are issues with the supply of relays at the moment - this is a known issue and will have to be overcome. EBI200 track circuits fell out of favour very quickly after they were first introduced - there is an element of me that believes they were used in preference to FS2550 to make a point about dual sourcing and not being tied to Siemens (Invensys) after some poor performance elsewhere on the SSR which then backfired. My personal feeling is that a 2550 with blockjoints is the best track circuit I've ever worked on - though they can be a bit fiddly to set up, whereas a Capacitor fed track is very simple to set up and test but the fault finding can be a bit involved. Regarding t697 's point about signal sighting - yes, lot has changed since the days of crew operated 1959 stock! Signal Sighting on LU wasn't massively considered until the advent of more modern stocks such as 1992TS, where a number of signals required co-actors to be fitted for close visibility. It really took off as an industry following the collision at Ladbroke Grove in 1999, though there are still some some really badly sighted signals out there. It's worth remembering back then we went from crew operated 59TS to crew operated 73TS which theoretically had better visibility thanks to the curved windscreen. Subsequent OPO conversion on the Piccadilly line caused changes to stopping positions as now the front cab had to be in the platform, rather than the rear cab for the guard's benefit, though in the tube this didn't have many issues in practice as there was only a limited range of positions available to install a signal. Where it mattered more was outside stations where the signal positioning wasn't really optimal before but now was made worse by additional furniture such as monitors or mirrors, and there was a greater chance of what became known on BR as 'ding-ding and away' SPADs where the driver lost the independent check on the signal aspect provided by the guard. A few high-SPAD sites have been provided with co-actors or additional repeaters over the years, though it is interesting that very little modification has been done to the majority of the Piccadilly line's safety signalling (with a few exceptions such as Heathrow) since the early 1980s.
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Post by Tom on May 4, 2020 12:17:09 GMT
The BR version of the London Connections map had certainly moved to black shading by the early 1990s.
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Post by Tom on May 4, 2020 12:14:49 GMT
Field End Road, Eastcote.
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Post by Tom on Apr 29, 2020 20:23:30 GMT
I'm not directly involved but I think they will be no longer than the 7 car 1959TS the present fleet replaced. But I accept that doesn't necessarily eliminate some signalling change. If nothing else, the replacement of the last 33 1/3 Hz DEVs with something else. Yes - we're already most of the way through eliminating the 10kHz Delta circuits and I had a discussion about doing the track circuit immunisation today. There's also talk of around 100 signals to alter/move as the cab sight lines will be worse than existing, just as we did for S stock.
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Post by Tom on Apr 28, 2020 19:45:47 GMT
No, please , no... not another train that doesn't fit around the existing infrastructure. We'll find (yet again) that it will give a trade-off between a few more passengers per train and the loss of a train berth somewhere along the line, with signal positioning optimised for trains of the existing length.
(Actually, bring it on - I had several years of gainful employment thanks to the individual that decided S stock should be longer than their predecessors!)
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