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Post by Tom on Oct 14, 2023 9:38:21 GMT
North Acton Junction, I think.
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Tom
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Post by Tom on Oct 13, 2023 10:36:10 GMT
A is Chesham.
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Post by Tom on Oct 8, 2023 21:05:35 GMT
The Aldgate layout is to be simplified soon. Renewed yes, simplified - we'll see!
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Post by Tom on Oct 3, 2023 19:17:22 GMT
All those evenings at City and Islington College 20+ years ago paid off!
Only thing to note is that it isn't/wasn't a signal cabin - not sure what it was though.
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Post by Tom on Oct 2, 2023 13:49:53 GMT
I also have very vague memories of something like 1 in a single digit over a distance of a few inches to get wheels over the running rail as part of trap points somewhere. I want to say Tower Hill/Minories sort of area but could be completely wrong. There were lifts like that on the old unbroken crossing noses for trains running towards the trap road, on one rail only. I don't think the track engineer would count it as a gradient though. Worth also remembering that the track engineers use "1 in x" to measure angles of crossings, rather than degrees, so it might have been a reference to the crossing angle rather than a gradient. (Edit: Just found the drawing and the rise was 1 in 80 and fall at 1 in 60 but they were both over quite short distances - the rail had to rise to 1 3/4" above the main line rail.)
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Post by Tom on Oct 2, 2023 13:45:48 GMT
Reminds me of Holloway Road.
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Post by Tom on Sept 30, 2023 8:54:05 GMT
Saturday 11 November is a software update for Jubilee Line and sub-surface areas, with no trains until approximately 13.10: Jubilee: no service 01.50-13.10 MET: no service Harrow-Aldgate until 13.10 District/H&C : no service until 13.10 This is actually a testing session, and it's a test that can only be done with a closure this big.
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Post by Tom on Sept 27, 2023 20:52:01 GMT
Sufficient training and no experience. Quite possibly so. Competence does not come from training alone; it is a product of training, experience, knowledge, and behaviours, demonstrated by consistent performance.
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Post by Tom on Sept 27, 2023 20:49:40 GMT
I would think that the 'outsourcing' of safety training has been a factor. Why have a highly trained specialist workforce, when you can just stop the trains and use contractors? Who suggested safety training had been outsourced? I don't remember reading that in the report.
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Post by Tom on Sept 26, 2023 19:16:56 GMT
Were these decisions and changes made following lineside workers being killed/injured? Yes. Mostly elsewhere in the industry than LU, but as the activities have decreased nationally LU has followed industry best practice and reduced the amount of track work carried out with trains running. These days concerns around being on or around live traction current has also been taken into greater consideration than had previously been the case. There was an incident on LU infrastructure last year where a train struck a worker on the track, who was incredibly lucky to have escaped with relatively minor injuries. Had the circumstances been ever so slightly different they would have probably been killed.
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Post by Tom on Sept 24, 2023 21:03:53 GMT
As Dstock7080 says, it was removed in stages in January 2019.
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Post by Tom on Sept 23, 2023 11:52:57 GMT
Two bay platforms at Willesden Junction long enough for 5-car Class 178s would require a lot of work on the station, which is why it was reduced to 1 bay. I can remember it as one bay back in the 1990s, when three-car class 313 untis were in charge!
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Post by Tom on Sept 23, 2023 11:51:19 GMT
I visited Copenhagen last year. Whilst on the train the signalling system failed and we came to an emergency stop in the tunnel, about 100m from one of the stations, and had to be detrained into the tunnel and back to the nearest station. Sadly I didn't get any decent pictures!
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Post by Tom on Sept 21, 2023 22:37:23 GMT
Maybe so, but there's still a need to install a platform extension. The bay road berth is 111m long (according to the NR sectional appendix), and there is only c.13.5m to the points which bring trains in from the Down DC or to the Up DC, which would make for an rather tight berth.
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Post by Tom on Sept 21, 2023 20:52:47 GMT
No, that's not really an option. There's only one bay road at Willesden Junction these days, and it is too short to accommodate an Underground train.
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Post by Tom on Sept 20, 2023 19:42:40 GMT
Yes, it still is. It was covered by the LT Museum's Hidden London Hangouts series on YouTube recently.
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Post by Tom on Sept 19, 2023 21:00:12 GMT
From the few videos of 1983 stock operations I've seen on YouTube they don't fill the platforms entirely, being six-car trains. Were there any operational difficulties when the 1983 stock shared duties with the longer 1972 stock trains? The difference was around seven metres (1983 Stock 106m versus 1972 stock at 113m). The line would have been designed for the longer stock (if not eight car trains), without the plethora of platform furniture and barriers that we are used to today and until 1988 both stocks were crew operated, though with the guard in the saloon on 1972 stock and in the rear cab in 1983 stock. I doubt there would have been many difficulties as the stopping positions would have been provided for the longer trains.
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Post by Tom on Sept 19, 2023 17:44:40 GMT
You beat me to it!
The info I have is 17.03.89 - units 3263 and 3551, which displaced 1959 stock units 1232 and 1055 to the Northern on 23.03.89.
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Post by Tom on Sept 13, 2023 16:53:08 GMT
Closing the Bakerloo Line for more than two years in order to reconstruct the depot recalls fears of a couple of years back My big fear is that we would have a repeat of a different experience from a couple of years back. The reconstruction of South Harrow sidings was originally planned to take nine months, but ended up taking more than two years.
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Post by Tom on Sept 6, 2023 7:31:54 GMT
Could either of these be adapted to accommodate exams and shed days whilst the current depot is closed for reconstruction? That would leave only the programme lift which may be one train a fortnight, and need to move between battery locos over TBTC signalling to Neasden, Ruislip or Acton Works. Neither is really suitable - Queen's Park has no road access, no crane, and current rails at ground level. Think of it more as covered sidings than anything else. London Road is arguably better but again has very poor road access (it's a tight turn and narrow access from London Road, possibly only achieveable from one direction) and is unsuitable for anything larger than a Transit van. The existing depot buildings would need to be demolished and the stores facilities inside would need relocating.
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Post by Tom on Sept 6, 2023 7:27:09 GMT
If you think the Bakerloo line gets hot during the day, you should experience it overnight with no trains moving and no air movement. It is unpleasantly hot.
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Post by Tom on Sept 4, 2023 10:42:13 GMT
Ignoring the depot, what "modified power supply, signalling and tunnel ventilation" work is needed to accommodate new stock, at least in the tunnels? Likely need for signals to be repositioned for the sight lines from the new cab. Ideally in a blockade-style scenario this would include moving signals and track circuit boundaries rather than the compromise solution of co-acting signals and delayed replacement controls we so often see.
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Post by Tom on Sept 3, 2023 8:17:12 GMT
That aside, spare parts must be near impossible to obtain owing to the fleet being over 50 years old but based on a design nearer to 60 years old. On the contrary, because 1972 stock is more electro-mechanical than electronic, it should be easier to obtain spare parts - you just have to have them re-manufactured. Unlike later stocks where certain microprocessors are obsolete or it runs on a software platform that nobody supports any more.
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Post by Tom on Sept 2, 2023 15:23:27 GMT
I assumed the approaches in part may be something to do in part with the 73 stock. They used to pull in quicker back in the day, especially pre refurb. Based on the date of birth on your profile, I doubt you will have strong memories of the performance of pre-refurbishment 1973 stock. I had several cab rides in them during my work experience in the late 1990s and I don't remember much about how they performed compared to a refurbished unit!
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Post by Tom on Aug 24, 2023 8:10:49 GMT
Looking to Plaistow from West Ham for the main photo.
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Post by Tom on Aug 23, 2023 21:09:36 GMT
I can't remember what the exact current arrangements are but I would not use the ILO drawings to make decisions in an incident, and nor would any controller - there are specific drawings for this sort of thing which are not made public. In practice it's not uncommon to take off a current section either side of the one you want to turn off, or to open section switches to make part of a section dead - which appears to have been the case here. Depending on the switches that were opened this would have prohibited reversing via the sidings.
What I don't understand is how you think section V05 (your description, not how it is officially known) would be fed from V06? The two sections are independent of each other.
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Post by Tom on Aug 20, 2023 14:27:46 GMT
That sounds like a tough ask to shave 30 seconds off the headway. I suspect it might be doable at some stations, but it'll still leave a 27tph pinch point at places like Kings Cross.
A lot of the auto sections are laid out with two home signals and blockjoints positioned to allow an easy installation of a third home signal should the need arise.
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Post by Tom on Aug 19, 2023 21:13:08 GMT
I really wish TFL were able to negotiate a deal now with the 4LM team(supplier) to rapidly extend their signalling system to the Piccadilly rather than messing about trying to eke fractional gains from the existing almost time expired signalling on the line. I appreciate there is definitely a case for commonality between 4LM and the Piccadilly line, however there are a few things to consider why a deal hasn't and probably won't be done. Firstly, TfL is very keen not to put themselves into a position where they are reliant on a single supplier, and, as a public sector organisation, they're not generally permitted to single source either. by the end of 4LM the split between suppliers will be: 1/11 lines (Piccadilly) LU designed and largely able to self-support for spares. 2/11 lines (Bakerloo and Waterloo & City) LU Designed with some reliance on Siemens for spare parts. In the case of the Waterloo and City line, the original design was done by Siemens (Westinghouse) but extensively modified by LU. 2/11 lines (Central and Victoria) Siemens (Westinghouse) designed, with significant reliance for spare parts (and in some cases system support and upgrades). 6/11 lines (everything else) Thales designed with almost 100% reliance for not just spare parts but also system support and upgrades. I imagine there would be considerable resistance to the idea of TfL putting any more of their eggs in the Thales basket - especially considering the possibility that Thales may well be taken over by Hitachi ( though I note it it currently under review by the Competition and Markets Authority) and the potential vulnerability of Thales' product line should such a takeover occur. Secondly, whilst the Piccadilly line signalling has now largely exceeded the original design life of 40 years, the principles of LU wayside signalling haven't massively evolved in those 40 years. The components are more or less the same and could be replaced on a functionally equivalent basis for a further 20 years without difficulty. The original signalling control system has been recently replaced with a system which can be supported for the next 20 years. If there is a desire to save money (which there undoubtedly is thanks to the Covid funding crisis) it could be argued that limited public funds should be spent in the most efficient way - which is to undertake targeted spending on the areas which need it for either asset condition or capacity constraints, rather than a wholesale replacement of the signalling.
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Post by Tom on Aug 18, 2023 16:30:30 GMT
I think there are several ways it could have been described - broken down train (without reference to what sort of train), or even 'late finish of engineering work' bearing in mind it's an Engineer's train. I don't think needlepoint precision on the description was either necessary or helpful for most passengers, though it's the sort of thing we (as enthusiasts) often take great interest in.
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Post by Tom on Aug 13, 2023 19:40:28 GMT
24tph = 150 seconds interval, 27tph = 133 second interval, so need is to despatch each train 17 seconds faster. How will further time be saved? Can more platform staff chase passengers along, or will more passages off the platform be needed, or will more home signals allow trains to get safely closer together? Exactly. Interval, or headway, consists of run time from from the sighting point to the signal, through the signal's control area, to when the back of the train passes out of the control area. The running time through the control area includes, where appropriate, dwell time - so home signal headways are almost always greater than starting or intermediate signal headways. The location of Kings Cross, at the end of a long, reasonably high-speed inter-station run, means signal overlaps on the home signals need to be longer to cater for the higher speed - plus there's the added complication of the crossover a short distance beyond the platform. All these things conspire to give the home signals a quite large headway. So part of the solution is either to get better at managing the dwell time, which I would suggest isn't going to be enough to get the time needed, or make some changes to the signalling, which also won't achieve the improvement required on its own. In theory, improved acceleration and braking performance helps but in reality train performance will be limited to match 1973 stock as the signalling is mostly designed around that stock's acceleration and braking characteristics. A number of changes were made about 20 years ago to try and make the overlaps protecting the crossover more robust - but it's likely that either some additional signals, some more speed control, or a combination of both will be required to further improve the headway.
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