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Post by jamesb on Jan 28, 2024 0:15:15 GMT
I came across an interesting post a couple of days ago in the Central Line Past and Present group on Facebook, and thought that members here might find it useful:
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Post by jamesb on Dec 15, 2023 0:10:02 GMT
I saw a letter today (dated 6th December) publicly displayed (taped to wall) at Roding Valley which stated "currently there are a high number of long term stopped units in the depots awaiting supply of traction motors and wheel sets which have been sent off to be reconditioned at the Railway Engineering Workshop (REW) in Acton. Unfortunately, there are delays in getting the motors and wheel sets back from REW which is causing the fleet to declare the high number of cancellations. However, our fleet colleagues are focussing on addressing the short-term casualty work, which means reconfiguring the trains, uncoupling 2 car units to make up a good 8 car train".
Hopefully it will get resolved soon, as it is noticeable especially at Roding Valley where a cancelled train can leave a very long gap of 30+ minutes - making it quicker to walk to Woodford or Buckhurst Hill...
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Post by jamesb on Dec 7, 2023 23:12:58 GMT
I wonder why so many trains are getting cancelled (more than usual...)? Is it anything to do with low railhead adhesion?
Incidentally, many of the trains that are in service are in a bit of a sorry state... I have seen a few trains running with graffiti on the outside of some carriages... Presumably they can't afford to take them out of service to be cleaned, because there is a shortage of trains...
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Post by jamesb on Nov 25, 2023 23:38:34 GMT
The train looks great. The LED lighting makes a big difference, along with the new seat covers. Although in the YouTube videos the train did briefly come to a sudden stop part way out of Hainault station! The announcements seemed very clear - did the train get new speakers as well?
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Post by jamesb on Jun 28, 2023 21:42:52 GMT
I had a slightly unusual experience this evening, at North Greenwich.
The service was suspended between North Greenwich and Stratford due to a signal failure at West Ham, so I got a westbound train towards central London from platform 2.
Firstly, the indicator board on platform 2 was displaying "Watford 15 min" as the 3rd departure.
Secondly, when my train departed, we were held outside Canary Wharf for a while (it felt like about 15-20 minutes). The (very informative) driver explained that the train ahead had developed a problem, so had to be reversed back into the platform at Canary Wharf and later said that it had become non-communicating. He referred to the signal failure at West Ham causing 'all sorts of problems'.
I wondered if the signalling system had been rebooted, and in the process the train ahead didn't come back online?
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Post by jamesb on May 28, 2023 18:12:38 GMT
Could just be coincidental, but the times I have seen the destination displays in the core not working have also been during delays.
Today, for example, there was a broken down train earlier at Custom House. The status of the line was severe delays. At Tottenham Court Road the boards weren't displaying real time information, instead showing 'severe delays on the Elizabrth Line'. When the train arrived they were displaying 'stand clear train not stopping'.
I wondered if the boards not working was connected to the broken down train, or if they intentionally turn them off when their are severe delays.
It is during delays that they are actually most useful, if they worked!
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Post by jamesb on May 11, 2023 19:02:08 GMT
IMO the main issue is about rapid communication with passengers in an emergency (or a perceived emergency), more than making external door valves visible. Could a generic automatic announcement be played every 15 seconds on a loop throughout the entire train when a passenger alarm is activated, such as "The driver is aware that the passenger alarm has been activated. Staff assistance is on the way"? Perhaps in a human, calm but authoratative voice... All that can be heard in the videos taken from inside the train is an urgent sounding beeping noise, which could feed into the anxiety rather than alleviate it. Having thought about my earlier post, maybe if a handle is pulled in more than one car, this could trigger the PEA system to go into 'panicking passengers mode' and default to playing a message to the entire train. The talk back facility doesn't seem to work well when passengers are panicking, multiple alarms are operated etc. If the driver has to leave the cab to investigate, they don't appear to be able to use the PA again until they have returned to cab. Maybe there could also be a readily accessible facility to operate the PA with a key from inside any car?
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Post by jamesb on May 8, 2023 13:36:29 GMT
Are there any restrictions on what people are allowed to carry with them on the tube? If well meaning workmen carrying builders tools were not present (as had been reported), it seems less likely that people would have smashed windows and climbed out of the train with such haste.
Using these tools while the train was in a tunnel, for example, could have very different consequences.
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Post by jamesb on May 6, 2023 23:31:43 GMT
It is very difficult to comment on situations like this without speculating. I'm sure that the numerous videos on social media will help with the investigation. The twitter post I just saw, containing 3 videos, has been viewed 1.3 million times since Friday evening! Helpfully, the dot matrix display clock is clearly visible at various points in the different videos.
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Post by jamesb on May 6, 2023 14:02:04 GMT
Could a generic automatic announcement be played every 15 seconds on a loop throughout the entire train when a passenger alarm is activated, such as "The driver is aware that the passenger alarm has been activated. Staff assistance is on the way"? Perhaps in a human, calm but authoratative voice...
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Post by jamesb on May 4, 2023 21:35:25 GMT
Is the derailment of an engineering train within the boundaries of the depot something that the RAIB would investigate?
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Post by jamesb on May 3, 2023 19:48:38 GMT
I commuted home to Roding Valley via Hainault earlier this evening, and passed a single wagon just outside Hainault that looked like it was in the process of being re-railed. It looked like it had lots of blocks underneath it, and there were lots of people with orange high vis vests.
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Post by jamesb on Apr 30, 2023 12:21:42 GMT
The replacement bus today (? CL5) was advertised on the TfL website as Stratford - Snaresbrook - South Woodford - Woodford but was actually going as far as Loughton. Presumably this is to take the pressure off Woodford? It seemed to stop at Roding Valley, Buckhurst Hill and Loughton.
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Post by jamesb on Feb 19, 2023 22:20:46 GMT
Over the past couple of weeks, I have seen two trains stopping abruptly on approach to North Greenwich in the evening peak - presumably because people are leaning on the doors as the train slows down. The trains are often quite packed, especially when there are minor delays.
After a short period, the train is restarted and slowly pulls in - on these occasions, it was only the second half of the last carriage that wasn't in the platform.
On my evening commute home, I have seen an external yellow light come on for a couple of seconds a few times as the train pulls into North Greenwich, and yet it hasn't come to a premature halt. So then I wondered if it was actually anything to do with people leaning on the doors at all/something else/if the train only stops if the door closed indication is lost for more than a couple of seconds?
It makes more sense for the train to stop if a door closed indication is lost when a train is pulling out of the station (in case a person/object is trapped in the door and getting dragged) or when the train is travelling between stations (in case a door opened for some reason), but when the train is pulling into the station, braking, and only half a carriage from stopping correctly, it seems much less likely that there would be a need (?for the software) to apply the emergency brakes?
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Post by jamesb on Dec 17, 2022 20:17:39 GMT
I bet that displeased many passengers who now had to vacate their seats and wait for the next train via Wanstead on a bitterly cold platform that has some snow om it. It did! But the driver was excellent in keeping the passengers informed, which makes a big difference. The same is not always true on the platforms, unfortunately. Today, a shuttle seems to be running between Epping - Leytonstone, Hainault via Newbury Park - Ealing Broadway, and North Acton - West Ruislip. The same thing happened earlier last week. Not ideal for people with reduced mobility/pushchairs/luggage - transferring at Leytonstone from eastbound platform 3, down the stairs, and up the stairs to platform 2 where the Epping service runs from. The status today is "severe delays due to train cancellations and earlier faulty trains" which implies that 'train cancellations' is separate to 'faulty trains' - a lack of staff?
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Post by jamesb on Dec 16, 2022 20:57:11 GMT
'Train cancellations' seems to be a regular occurence lately, and is a bit of a catch all phrase that avoids explaining why the trains are cancelled.
Are the trains cancelled because of faulty trains, or because of a lack of available drivers, or a mixture of both?
At Leytonstone this evening, I got off an eastbound Hainault via Newbury Park train, which remained in the platform for a good few minutes because there was no driver. The driver who was waiting to be relieved said that we would wait on the platform until the new driver came. Unfortunatley, no driver did come and with two Epping branch trains immediately behind, the destination was changed to South Woodford and the original driver continued to the sidings at Woodford. At Leytonstone, it all felt a bit last minute.
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Post by jamesb on Nov 6, 2022 18:54:16 GMT
I had a similar experience at Stratford, on a Paddington bound train.
The train seemed to wait for a while and the driver announced that there was a problem switching over to the new signalling system. He then said that we would pull up to the next signal and try to switch over to the new system again, but that if it wasn't successful, we would be diverted to Liverpool St mainline platform.
So we left the platform and waited for a minute just outside the station. Thankfully, the switch was successful and we continued to Whitechapel.
Just teething problems hopefully!
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Post by jamesb on Sept 4, 2022 19:53:44 GMT
Will London Underground be impacted by the rising energy costs, given the hugely significant rises? It is my understanding that power has been supplied to the network from the National Grid since Lots Road Power Station shut in 2002. I came across a public document on TfL's website ( TfL Energy Purchasing - Crown Commercial Service) that had a few interesting points (if I have interpreted the document correctly): - TfL uses annually the electricity of about 420,000 domestic electricity consumers - The Crown Commercial Service purchases electricity 'en masse' for TfL and other public sector organisations, giving it greater leverage to get a good price. - The electricity is purchased in advance at an agreed price, a year at a time, and about 2 and a half years before it is actually supplied. Meaning the electricity that is used for the next couple of years has already been purchased, at prices before cost of energy went through the roof. But presumably, electricity to supply the network after 2024/2025 will have to be purchased sooner or later... Even with the collective bargaining power of the Crown Commercial Service, it is hard to see how such a huge consumer of electricity could avoid the impact sooner or later?
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Post by jamesb on Sept 3, 2022 22:54:23 GMT
I wonder why some (the majority) were replaced but a few of the 90s version have remained? The replacements were a bit brighter but you still have to be near enough to read the text. Were the replacements linked to the Metronet station refurbishments, back in the day? The new displays are too small and the letter heights far inferior to the previous displays. I think there are a few different dot matrix boards now in existance. I tried to link to third party photos of them but it didn't work. 1) The original 90s display (with green and orange LEDs) 2) A similiar proportioned display with all orange LEDs, that replaced some of the 90s displays (? in the Metronet era). As I recall, the 90s displays seemed to be working but were replaced anyway at many stations. The LEDs are a bit brighter. At around this time indicator boards also appeared in the ticket hall (which seem of very limited use, especially at Roding Valley)! 3) More recently, smaller ones such as those at Bank. I agree that these are too small to read - unless you are standing right in front of them.
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Post by jamesb on Sept 3, 2022 17:51:38 GMT
I wonder why some (the majority) were replaced but a few of the 90s version have remained?
The replacements were a bit brighter but you still have to be near enough to read the text.
Were the replacements linked to the Metronet station refurbishments, back in the day?
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Post by jamesb on Aug 25, 2022 20:24:51 GMT
I am way out of my depth here and have a very simple mind (confirmed by just answering about 1/3rd of the questions on an IQ test, probably incorrectly, as part of a job application!), but I have read that Bombardier have several families of traction motor products, and it is the MITRAC1000 family that is used on the "SSL and VLU" (I presume VLU refers to the Victoria line). I found the overview product brochure for MITRAC1000 here. I found it quite interesting, but I am not sure if it adds much. Presumably, the 92S AC motors would be something along these lines? As a lay person, when I read about "improved performance" it initially made me think of the train accelerating more quickly, or the train travelling faster. But having read a bit more about it, "improved performance" can refer to many things, some of them quite technical - like energy efficiency, reduced life cycle costs/maintenance etc.? Improved reliability we will (hopefully) notice - in terms of less cancelled trains/less broken-down trains. I get the impression that the actual speed and acceleration of the modern London Underground train (?1992ts onwards) is influenced by a whole range of factors above and beyond the technology on the train itself, and is probably already at the upper limits of what is feasible – given the power supply, track, limited space/safety, and comfort of the passengers etc.? Mod edit [Antharro]: Quote 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 jamesb on Aug 23, 2022 21:12:06 GMT
I travelled on the W&C line recently and saw a wheelchair bay, which felt like a bit of a sneak preview of what might appear on the central line. The train also had a new cab security device fitted to the J door (appearing to be similiar to what has been discussed previously - districtdavesforum.co.uk/thread/29860/cab-security?page=6) I wonder if this will also be fitted as part of the 92ts refurbishment?
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Post by jamesb on Aug 21, 2022 0:11:02 GMT
The general point was that transplanting motors which are more powerful into a train that is 30 years old could have unintended consequences, so I hope some testing takes place in a crush loaded train! Are the new motors more powerful though ? This is DC motors replaced by AC motors and all the associated power electronics gubbins. Does not automatically imply more powerful - the project might specify this. AC motors have different characteristics to DC motors and any planned point to point running time changes could simply be taking advantage of these differences, plus AC motor traisn require significantly less maintenance time so they can probably squeeze 2 or more complete trains for traffic out of the fleet (once the whole lot are done). I do not recall seeing any power or other performance values quoted for the new kit, not in this forum, nor anywhere else. I might have missed it if I did not get a search keyword right of course. Can you cite some authoritative actual performance values for 92TS in their upgraded form ? Good point - I don't know, and I don't have any actual performance values, aside from the anecdotal comments further up in the thread: A mate of mine who is a Test Train Op has confirmed the trains are faster and perform much better. I may have confused 'increased performance' with more powerful. 1.3m/s^2 maximum acceleration seems to be mentioned for 2009 and S stock, and if the current 92ts is also the same, perhaps the new AC motors (/software) won't change that. Having tried to read various past posts, I have seen it mentioned that anything greater than 1.3m/s^2 (? 1/8th 'g') is uncomfortable for passengers, given it isn't a fairground ride... so that might be another reason capping the maximum acceleration, whatever the motors are actually capable of. Given the age of the Central line trains compared to the later Victoria line/sub surface stock, it is actually quite impressive that they are already capable of 1.3m/s^2 acceleration!
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Post by jamesb on Aug 19, 2022 17:12:35 GMT
I do not recall other train fleets having the same 'Kangaroo Hop' mode as the 1992ts. Maybe its more of a problem on this fleet than older fleets because the doors are externally hung and later fleets had the door mountings designed to reduce the frequency of this issue? I too haven't experienced the same 'Kangaroo Hop' on other lines. I wonder if the shape of the doors, and the larger windows, make it more of an issue on the 92ts? My understanding is that newer trains (2009/SS stock) have a sensitive edge which negates the need for a door leaf to be able to be pushed open to free an obstruction, because the sensitive edge would allow an obstruction to be detected, prompting the doors to be reopened by the driver. So on newer trains the doors don't have the same pushback mechanism? (I recall that on the 2009ts the sensitive door edge caused no end of problems in the early days, but the design was subsequently tweaked). The general point was that transplanting motors which are more powerful into a train that is 30 years old could have unintended consequences, so I hope some testing takes place in a crush loaded train! 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 jamesb on Aug 18, 2022 21:34:05 GMT
It is great if the performance is improved but the 1992ts seems more prone to motors cutting out when people lean on the doors - causing the train to jerk (or occasionally crawl along at a snails pace until the driver stops and restarts).
So I wonder if the train having a bit more punch when it pulls out of the station might exacerbate that problem - especially in rush hour?
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Post by jamesb on Aug 13, 2022 9:53:52 GMT
So the rail network is actually quite resilient, which is reassuring!
Doing some digging, according to Network Rail (https://www.networkrail.co.uk/campaigns/hot-weather-and-the-railway/) it would seem that speed restrictions are imposed during the hottest part of the day (at least on the National Rail network) when the forecast air temperature is over 36 degrees.
So it makes a bit more sense that things aren't disrupted today (when the predicted high is 35 degrees).
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Post by jamesb on Aug 13, 2022 8:30:03 GMT
What is the temperature threshold for heat related TSRs to be introduced? Today, according to BBC weather, it will be up to 35 degrees in London, but there doesn't seem (on the TFL website) any mention of potential disruption.
Yet 35 degrees doesn't seem to be that far away from the temperatures we saw in July, which caused widespread disruption and strong recommendations not to travel.
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Post by jamesb on Jul 22, 2022 12:25:33 GMT
Oh right. I didn't find that when I looked at the TfL website after reading the initial tweet from Greater Anglia (which has since been deleted!), but it's good that it did appear (even if it later disappeared!). Could be a lesson for me not to spend too much time perusing Twitter! The communications of the potential closure today was a bit messy. The first heard about it was from Greater Anglia in a Tweet (nothing on TfL website). When questioned about whether or not the Tweet was a mistake, the Greater Anglia person replied "afraid not - this is what we've been told by their control room". TfL seemed to manage to make themselves look even worse by the drip feed of Tweets from various sources, in advance of anything official from TfL. And then the whole thing was reversed! The e-mail that I received from TfL came after I had seen the tweets. I would have valued a banner on the TfL website, stating "potential disruption on the central line this evening" linking to a page explaining a shortage of staff caused by sickness, but stating that "we are doing our best to find a solution, and we will keep you updated. Check back here for further updates. In the meantime, please plan an alternative to the central line from 5.30pm onwards". The status page said 'Part closure, Reduced service' 'Thursday 21st July, From 1800, no service between Leytonstone / Ealing Broadway / West Ruislip and between Woodford and Hainault. Please complete journeys from the central area by 17:30 then use alternative rail or bus routes, or alternative London Underground connections. Use Bus connections from the Elizabeth Line at Ilford / Manor Park to the Central Line at Newbury Park. Use bus connections from the Piccadilly line at Park Royal for Hanger Lane, or North Ealing for West Acton.'
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Post by jamesb on Jul 21, 2022 17:52:23 GMT
The communications of the potential closure today was a bit messy.
The first heard about it was from Greater Anglia in a Tweet (nothing on TfL website). When questioned about whether or not the Tweet was a mistake, the Greater Anglia person replied "afraid not - this is what we've been told by their control room".
TfL seemed to manage to make themselves look even worse by the drip feed of Tweets from various sources, in advance of anything official from TfL. And then the whole thing was reversed! The e-mail that I received from TfL came after I had seen the tweets.
I would have valued a banner on the TfL website, stating "potential disruption on the central line this evening" linking to a page explaining a shortage of staff caused by sickness, but stating that "we are doing our best to find a solution, and we will keep you updated. Check back here for further updates. In the meantime, please plan an alternative to the central line from 5.30pm onwards".
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Post by jamesb on Jul 20, 2022 16:42:25 GMT
Of course, it is common sense that if the rails are at all at risk, going slower is sensible (doing everything slower in the heat was generally the advice of the day). According to this BBC news article slower trains exert less force on the track, which reduces the chances of buckling happening. That would imply that the main safety aspect of the speed restriction was more about preventing buckling from happening in the first place? While the speed restriction would obviously reduce the impact of passing over a defect (or allow the train to stop in advance of it) if the risk of the track buckling, even with trains running at a reduced speed, was that high one would imagine that the trains would not have been allowed to run at all, given the unprecedented UK temperatures. Great respect to those with the engineering knowledge of how these things all work - such as being able to calculate a safe speed for the trains to traval at etc. Especially since they pass a few meters from the end of by back garden!
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