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Post by 100andthirty on Jul 25, 2022 9:58:09 GMT
As always the issue is power measured in kilo Watts or Mega watts. The 2009 tube stock can draw much more power from the conductor rails than is allowed on the 1973 tube stock, and it uses it to good effect. But Victoria line has the benefit of modern signalling laid out to allow the trains to make use of that performance.
As t697 has said up thread, 1973 tube stock is capable of being faster but has to operate within the constraints of the signalling system. Modern trains with solid state traction equipment can be programmed to perform a little better within the constraints of the existing signalling system. Explaining this would take us way outside the subject of this topic.
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Post by 100andthirty on Jul 25, 2022 9:51:31 GMT
I suspect your first point is relevant. Hand notching could give a bit of extra oomph (a technical term!) which the automatic notching wouldn't have allowed.
Mod note: Quotes removed. Please be selective about the part of a post you wish to quote rather than the whole post verbatim, particularly if you are replying to the previous post in the thread.
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Post by 100andthirty on Jul 24, 2022 10:31:41 GMT
The thread title seems a little at odds with the content if the units were from 37 years ago. They were newer than the old locos. LU has looked at newer locos more recently but cash has always been a issue and it's always been much cheaper to upgrade the 1964/1973 locos. The 1985 locos were really poor for several reasons: 1) they were less powerful than the old locos - a bit of a snag when the old locos weren't all that powerful. They were built around reclaimed CO/CP stock motors which were less powerful that the Q stock type used on the older trains; 2) they were more technologically advanced than the old locos, which required a major uplift in skills for the maintainers - but there were only ever 6 of them which meant that many never really used their skills and 3) they weren't all that reliable. This led the Transplant folk to rely more and more on the old locos and they realised that they could deliver all that was required without the new ones. Hence the new ones being displaced.
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Post by 100andthirty on Jul 21, 2022 18:21:00 GMT
It was converted to act as the track recording train in about 1987. The computer wizardry has been updated several times since then. There was a grand plan to run the 1973 car on Southern Region tracks in order to calibrate it against British Rail's TRC. In order to enable this, the couplings at both ends of this car and the trailing ends of the 1960TS motor cars were converted to standard Southern buckeye couplers and centre buffer at main line height, with two pipe air connections and 27 way jumpers. This did happen once or twice but not for a long time, and of course all the trains it could have coupled to have now been withdrawn. The disadvantage of all this is that the R and S doors are rather short. One had to bend double to move from car to car.
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Post by 100andthirty on Jul 4, 2022 17:55:12 GMT
THIS is my Rail Express article from November 2014 re the potential cascading of stock re the Northern/Jubilee Lines... in the end the ITT for the extra trains specifically required them to, effectively have the same form, fit and function as the original trains. This was a challenge apropos the Alstom intellectual property as indicated in the article. They did in fact invite competitive bids from CAF as well as Alstom. It is a matter of great speculation as to why the contract was never placed. Mod edit [Antharro]: Quote partially removed. Please be selective about the part of a post you wish to quote rather than the whole post verbatim, particularly if you are replying to the previous post in the thread.
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Post by 100andthirty on Jul 4, 2022 17:47:05 GMT
marri260: It's an obvious requirement that the driver needs to see the signals. The new fleet introduces a number of changes. Firstly, it is some 7 m longer than the old train and in some stations the train will have to stop with the cab in the tunnel. This means that the driver might not be able to see the starter signal and the signal might need to be moved. Secondly, current crashworthiness standards means that the driver will sit further from the windscreen, and the sighing though the windscreen will be narrower than on 1973 tube stock. Again this might mean signals will have to be moved. Thirdly, at other locations the train will stop further back from the signal so the driver can see it. This might affect how track circuits are cleared, and might affect capacity. The first two really only require engineering capability to lay out drawings/some basic geometry. The third might need some limited signalling knowledge, but with the support of someone like this forum's Tom, Costain would be able to do the rest.
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Post by 100andthirty on Jul 3, 2022 12:23:52 GMT
Hi all, hope you don’t mind humouring my slightly random question? Was a stock cascade ever considered as a way of assessing issues on different lines? As I understand it, additional stock is one component that could facilitate proposed service pattern and frequency changes in both Northern and Piccadilly lines. Was there ever consideration to prioritise an order for enough newtfL trains for an enhanced/split Northern line, which would allow the 106 1995ts to serve the Piccadilly (in combination with resignalling and takeover of the Ealing Broadway branch)? Be assured that all sorts of ideas were brainstormed when developing the plans for the deep tube stock. Transferring 1995 tube stock was one of the more problematic ideas, quickly binned, as the trains aren't TfL's and the maintenance is contracted out. It would have also harmed the idea of increasing capacity though the extra 7 m of train length. Splitting the Northern line in two remains an objective that can only be realised when Camden Town is properly remodelled, at least at platform level, to enable easy cross platform interchange between the branches. One suspects that none of this will happen until the time comes to replace the trains, though perhaps the idea of replacing the Jubilee trains and transferring the 1996 tube stock to the Northern line having reverted them to 6-car might be resuscitated. I doubt if anyone is paying too much attention right now in the absence of a firm funding agreement.
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ATO
Jun 15, 2022 18:14:45 GMT
Post by 100andthirty on Jun 15, 2022 18:14:45 GMT
Another drawback with ATO is if the train underruns at a station where the Starting Signal is red, the Target Speed for the next signaling section is obviously zero and there is a limited time in which you have to switch to Coded Manual and pull up to the signal/fully berth train into the platform before being "code tripped". In this instance, it's safer/more practical to wait for the starter signal to clear or radio the signaller for authority to fully berth the train, preferably in CM but it may be necessary to do this in Restricted Manual if the signaller gives you authority to do so. It depends on the location, but you should be able to pull up to a red aspect without being code tripped. In auto areas it's not a problem, but in controlled areas the code can be removed from under a train when it's been proved at rest for a set period of time - either because the signalling system has called for an overlap when the train runs in, and now it's at rest it doesn't need to lock that overlap (allowing for a shunt move to a siding, for instance), or the turnaround berth code timer has run. This takes the code off the front of the train ready for it to be applied to the other end if the train reverses. From memory the overlaps time out after fifteen seconds and turnaround timers after 30 or 60. When it comes to rain, the worst type is not heavy rain but a light, misty rainfall - despite many years of trying various fixes the ATO still struggles with light rain, when it starts to brake, has a bit of wheelslip or slides, loses where it is and pulls up in a heap as others have described. Regarding rain, What Tom has described is an issue for all ATO systems. The SELTRAC systems can select lower braking rates (and, on SSR, motoring rates) to try and minimise wheel slip or spin. Research continues on having reliable/safety rated speed/position determination that doesn't rely on wheel rotation. Some use Doppler radar, others use accelerometers but this is in addition to the tachometers, not instead of. There's probably a debate to be had at system level about how much wheelspin/disagreement between tachos is allowed before trains come up in a heap! The ATP system designers tend, reasonably, to be rather conservative.
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Post by 100andthirty on Jun 14, 2022 18:43:20 GMT
t697.........get out there influencing the 2024 TS project team!
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Post by 100andthirty on Jun 14, 2022 11:46:19 GMT
Modern trains more power hungry, air-conditioning etc. Siemens themselves quote that the new trains consume 20% less energy - but I don't doubt what Dstock7080 is saying, as it's been a rule of thumb for generations that a new fleet of trains uses more power than that is replaces. So how is the 20% saving achieved? Is the power drawn in short, large intensive spikes, requiring upgrades to the supply, but for the rest of the time draw is much lower? Or is it to do with the regenerative braking and the overall/average energy? There is a variety of things that contribute to the impression that the need to upgrade the power supply is in conflict with the lower power consumption of the trains. The big contributor to reduced energy is the regenerative brake. The Victoria line is a good example of how more performance is delivered with less power. The maximum current allowed was increased to 4500 A to accommodate peak traction and braking power flows. But coasting was enabled, reducing power demand. In short, the peak capacity went up from 27 trains/hour (TPH) to 36 TPH. Run time was also reduced, meaning that 27 TPH was delivered with 37 1967 TS trains and 36 TPH with 41 2009 TS trains. All this led to a 30% increase of capacity and the impact on power consumption (electricity consumption not peak current) was a 16% reduction. On the Piccadilly line not all these benefits will be delivered until the signalling is replaced and ATO introduced.
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Post by 100andthirty on Jun 10, 2022 6:50:33 GMT
It seems that the new trains will be initially restricted to perform as 1973 tube stock that they replace, but those trains still remain restricted as the 1959 tube stock that they replaced. The 1959 tube stock was a post-war build of 1938 tube stock, and inter-worked with some of those trains, so I presume had similar performance. Does that mean that the new trains will perform as Piccadilly trains have over almost 90 years! Surely the new trains will know their location and, once the old trains have all gone, could have improved performance in areas resignalled since the 1973 stock was delivered? Amazingly 1959 tube stock had worse performance than 1938 tube stock. This meant that the remaining 1938ts on the Piccadilly had to be restricted (series only on one motor car if I recall directly. This was an issue for the S stock where a whole variety of restrictions on different parts of the SSR could have led to very restricted 0erformance ( e.g., very poor performance north of Finchley Road). An automatic flag switch system was superimposed on the CSDE system, which already had a suitable safety rating. As far as I recall the performance selected was C stock flag down and A stock flag up. I'm sure t697 will be along to explain more. Perhaps this can be done for the Piccadilly line trains.
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Post by 100andthirty on Jun 9, 2022 16:51:43 GMT
I heard someone recently refer to a train failure as a significant thermal event. I said "do you mean in caught fire?" The response was "yes".
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Post by 100andthirty on Jun 5, 2022 11:57:17 GMT
The plan was always to get back to the length of a 1959 tube stock 7-car train - about 7 m longer than the 1973 tube stock - 113 m vs 106 m. A bogie car has a similar bogie centre dimension to a 1972 tube stock - about 1 metre shorter than a 1973 tube stock.
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Post by 100andthirty on May 6, 2022 16:22:27 GMT
I have yet to see any show involving the railway- even those, like this one which is focussed on the railway where the continuity is perfect. My guess is that the budget is so tight that if they "forget" to take a particular shot, there in no money to go back and film it again It’s not so much the budget, more the access. Most of the overnight shoots were arranged around other possessions and staff availability, which are planned quite far in advance. Sometimes it also simply isn’t possible, for whatever reason, to get the required shot. Whilst not perfect, this is by far the best of the many series on the Tube over the years. Whilst I should acknowledge that I appear in it, the production team have worked very hard to create a great finished product - my honest opinion, not biased by any appearances or otherwise. We should also remember that some of those involved in the production may or may not be members of this forum, and read comments presented.MoreToJack - I agree with your sentiment. I was making the point as an observation, not to be critical and the odd lapse does nothing to spoil my enjoyment of the show. I was delighted to hear that it is the Yesterday channel's most viewed original production; well deserved.
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Post by 100andthirty on May 6, 2022 11:49:03 GMT
I have yet to see any show involving the railway- even those, like this one which is focussed on the railway - where the continuity is perfect. My guess is that the budget is so tight that if they "forget" to take a particular shot, there in no money to go back and film it again
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Post by 100andthirty on Apr 17, 2022 18:25:11 GMT
Many of of the LT Museum's Hidden London Hangouts on YouTube have visited disused tunnels. The Angel episode is an example.
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Post by 100andthirty on Apr 16, 2022 13:48:43 GMT
Or, to ask that question, are any S8 being dealt with at the S7 depots ? Not currently, no. As for the rest of your post, you are assuming that the solution to the problem is run all the defective wheelsets through a wheel lathe. It could be the case that the defective wheelsets could be so far out of tolerance that they cannot be corrected by re-visiting a wheel lathe.... Or, it could be the case that the last turning took the wheels down to the minimum diameter for a newly turned wheel.
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Post by 100andthirty on Mar 26, 2022 15:55:27 GMT
As I understand it, on Central line there will be few, if any locations where wheelchairs will be able to board or alight without the assistance of a ramp manoeuvred by a staff member (excessive gap due to the configuration of the doors/lack of sills). Said staff member will, no doubt help find space. This is more of an issue on other lines where level access is provided and no staff assistance is required Yes well especially at the former LNER (etc) stations to the east of Leyton the larger than usual gap between train and platform still exists - this dates from when mainline trains (which are wider than tube trains) used the route. (Utopian cloud cuckoo-land comment:) Since the route nowadays is only used by Central Line tube trains so if there was a magical money tree somewhere then these stations could, I suppose, be made fully accessible (without staff assistance) by means of the tracks being realigned to reduce the lateral gaps and also change the track height to facilitate a same-level platform / train interface. Oh and at some of them lifts etc., being installed. It would also require a significant modification to the train doorways. On all tube trains, except central line (and W&C) the floor extends to or just beyond the external line of the door. On Central line the floor is inboard of the door. Allowing a nominal 75mm between platform and door, this means that the gap on the 92 tube stock is in the order of 95mm to 100mm.
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Post by 100andthirty on Mar 25, 2022 12:21:32 GMT
Do wheelchair users fare well in the rush hours? My thoughts are that at some stations they will find it difficult to board a train as it will be rammed full of passengers - and in that condition it will simply not be possible for enough passengers to move out of the way to create space for the wheelchair. Oh and at off-peak times do wheelchair and pushchair passengers clash / fight for space as they sometimes do on buses? Or is there nearly always sufficient space for them both? As I understand it, on Central line there will be few, if any locations where wheelchairs will be able to board or alight without the assistance of a ramp manoeuvred by a staff member (excessive gap due to the configuration of the doors/lack of sills). Said staff member will, no doubt help find space. This is more of an issue on other lines where level access is provided and no staff assistance is required
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Post by 100andthirty on Mar 22, 2022 21:54:49 GMT
The sections of saloon by the articulated sections are quite long, I don’t know if they’ll be the same 6 seats long either side, but that will increase dwell times for loading and unloading, it’ll be like having a double ender middle cab each articulated section… It’s a long bit of saloon with no doors in essence… The next pair of double doors is two windows past the articulation, so less than 6-seats. In the bridge cars, there's planned to be two seats between the gangway and the first doorway. Siemens make all their bogies in Graz, Austria. I'm sure they have a central location where they make traction equipment, but I don't know where. The first train is being built in Vienna, a large factory used to manufacturing aluminium vehicles. I don't believe anyone has yet declared whether Goole will be able to manufacture the bodies or whether they will assemble everything on bodies manufactured elsewhere.
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Post by 100andthirty on Mar 6, 2022 16:43:35 GMT
When LU was investigating driverless trains back in my day, there was a non-negotiable requirement that the track (area between boundary fences) would be maintained as a people free zone. At stations, the use of Platform Screen Doors achieved that objective. In the open, secure fencing either side of the railway and at bridge parapets was also a means of achieving that objective. Where the railway shares tracks with other lines (i.e.) north of Queen's Park, the railway is hard to make people free given the lines that leave and join. In the previous work, it was assumed that these areas would have a staff member on the train looking out.
Apropos double length platforms, both faces would need PSDs if the people free principle were maintained. Stations with obstructions at both ends are the challenge - Kensal Green, Willesden Junction as already mentioned and Stonebridge Park.
I keep returning to the cost:benefit business. Political opinions are offered on the basis that there's a good business case. As I've said before, the overwhelming benefit is derived from new trains, signalling and ATO. Driverless is worth <think of a phrase meaning "not a lot" beginning with B>. The cost of doubling the length of platforms north of Queen's Park r tunnelling would just wipe out any benefits
That said, in the current situation, if I were the Mayor, I'd be supporting the PM and telling him how much it would cost, with an incremental benefits delivery programme involving new trains, signalling ATO and then PSDs. By the time the trains signalling and ATO is delivered both the Mayor and the PM and commissioner would be long out of office, the new team can quietly forget the last part of the programme.
The other myth of driverless trains is that it "breaks the power of the unions". Even driverless lines need staff, just in different jobs. Those people are likely to be union members and if they are not in place the trains won't run.
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Post by 100andthirty on Mar 3, 2022 20:53:34 GMT
well yeah why not look at glasgow subway - that has no sudewalks in tunnels its possible evacuate via front or rear doors at ends - simllar to singpore where ramps installed to allow evucation to track As for Glasgow, it is running very late. The contract for the upgrade was placed in 2016, the first train was due for delivery by 2019 by which time the new signalling and comms had been expected to be in place to allow the new trains to run. In fact the new train only entered the tunnel for the first time last December, and the current plan is to run the new trains with the old signalling for a while. I'm not holding my breath for unattended operation any time soon.
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Post by 100andthirty on Mar 3, 2022 20:50:24 GMT
Surely all they need is a short document that says "to upgrade to 'driverless' will cost X, cause Y disruption and save Z in anual running costs for reasons a, b and c. It is therefore uneconomical. If the DfT would like to proceed, please sign a blank cheque." TfL has been talking about and estimating for driverless trains off and on for over 30 years. Many reports have been completed. The overwhelming majority of any benefit of moving from driver operated trains to driverless is delivered by the conversion to ATO. ATO delivers significant performance capacity and regularity benefits. Having unattended trains means that the whole track area needs to secure. that's one reason why platform screen doors are considered essential. Then there's a layer of systems and communication required to help manage situation where the train stops away from the platform and the passengers have to be rescued. PEDs might just be justifiable on safety benefit alone, but for the rest, keeping a train operator on the train provides a flexible, thinking presence to help sort out things if the train fails. in short, moving to ATO has a very positive business case. Taking the next step to driverless hasn't. This is a consistent outcome of all the studies carried out by different people, including those who would enjoy the technical challenge.
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Post by 100andthirty on Feb 22, 2022 11:54:48 GMT
Both the 1986 tube stock and 1992 tube stock had the body ends constructed separately from the rest of the car and were fitted later. 1986 tube stock used composite materials for the body ends and 1992 tube stock used aluminium. I think it's well known that many of the body ends "didn't survive very well" (delicately put!). The joints between the body and the ends were sealed with what was claimed to be a "flexible for life" sealer. I remember escorting a senior employee from the supplier around one of the depots and explaining about the flexible for life sealer, before stopping adjacent to a body end, and digging out a piece of filler which I snapped in two in front of him. The material had set solid and wasn't sealing anything. This was the reason for all the tape!
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Post by 100andthirty on Feb 16, 2022 14:41:59 GMT
Aluminium does corrode, but unlike most steel, the corrosion sticks to and protects the metal underneath. Another factor is that the volume of aluminium oxide is much bigger than one might expect. And if water, mixed with, say, cleaning fluid gets lodged in "nooks and crannies" then some comparatively large amounts of aluminium oxide powder can be produced. I remember this being demonstrated in chemistry lessons at school many years ago.
the original glazing system for 1992 tube stock involved bonding the windows to the body rather like the process for securing most modern car windscreens. This requires an excellent chemical bond to the glass and to the aluminium aperture. This involved meticulously preparing the aperture and treating the surface that receives the adhesive with a suitable etch primer to deliver a much better bond than would be achieved if the adhesive was applied to the bare aluminium. Based on what was found both in replacing loose windows and later when the new window frames were fitted, attention to detail on both the quality of the manufactured apertures and the quality of the etch priming was sometimes not up to the standard. Thus there were some of the "nooks and crannies" that allowed water to collect.
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Post by 100andthirty on Feb 15, 2022 7:33:15 GMT
Many welded aluminium bodyshells are manufactured with no window apertures and they are cut out later.....think giant can opener!
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Post by 100andthirty on Feb 14, 2022 18:52:13 GMT
From what I remember (having been in the cab of the Green train several years later) the cab layout was very similar to that of 1983 Tube Stock - hence running it on the Jubilee line. At the time various parts of the Central line used 33⅓Hz track circuits (the Ealing Broadway branch was one such section) and the 1986 stock with various experimental electronic devices would have probably been prohibited due to Electro-Magnetic Interference concerns. Indeed, the control desk was the same as in 1983 tube stock as extras were bought and free issued for the 1986 tube stock. In addition LU managed the contract with Plessey (now Siemens) for the control and monitoring system so that it could ensure that the electronic systems across the three trains from two different manufacturers would talk to each other. 1986 tube stock was helpful in a number of ways. It showed that welded aluminium bodies would work well, that steering bogies were a step too far and that overhead door operators using rubber belt drives (as per the concurrent class 508/317 designs) didn't work well on the curved doors of tube stock. The most efficient structure was the version supplied by BREL. Sadly when they won the contract, they adopted the Metro-Cammell layout instead. And finally, the first two trains of 2009 tube stock were, effectively prototypes. Once their testing work was complete, they were returned to Derby to be brought up to the standard of the others. They changes were VERY extensive.
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Post by 100andthirty on Feb 10, 2022 6:39:36 GMT
ChrisL. Bogies were originally from Kawasaki. They were replaced just over 10 years ago with bogie frames by Siemens. The latter have been trouble free.
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Post by 100andthirty on Feb 5, 2022 17:54:42 GMT
The work to modify the trains might be prohibitive - fitting standard Correct Side Door Enable equipment, fitting a more permanent tripcock, etc just off the top of my head, but there are probably other alterations required. If the Bakerloo passenger numbers are lower, then perhaps a six car formation rather than seven? The are designs available for the modifications Tom mentions as these systems are fitted to the W&C cars. Buth they're just the tip of a rather large iceberg. 1992 tube stock was designed based around 2-car units and most of the expensive systems (traction equipment auxiliary converter, compressor) are distributed across the two cars in each unit. So just using one of them leads to lots of modification. Even the notion of converting a car into a trailer car to be inserted in a B-C unit is far from trivial. There is nothing extant to control just the friction brakes on a trailer car. None of the suspension is set up to support a trailer car and it might well need to be ballasted to maintain the weight. Then there's the issue of steps and gaps at the curved platforms. 1972 tube stock has sills that extend slightly from the bodyside. 1992 tube stock doesn't have these. Thus all 1992 tube stock steps/gaps will be about 50mm worse than on 1972 tube stock.
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Post by 100andthirty on Jan 31, 2022 20:43:01 GMT
That's what I make it........about 2.3%
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