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district, circle and hammersmith and city lines - reorganisation idea
My plan for the circle, district and hammersmith and city lines (feel
free to shoot it down) is based on the following: 1)existing frenquencys should be pretty much kept to. 2)olympia should have 6 trains an hour 3)lines shouldn't have lots of branches sprouting everywhere as confusing 4)lines should be kept reasonably short, so as to try to reduce delay here is a current off peak service diagram for the subsurface lines (note values such as 7.5 have been rounded up) ham----8---edg---16 | \ 14 \ | \ oly hsk ls | | |\ 4 10 8 8 8 \ / \ / \ eb-6-tg-12--ec-18-gr-26-t-12-ae-20-w-16-b-12-u / / 6 12 | | rich wim I propose these services: 4tph olympia-tower hill-hammersmith 4tph wimbledon-tower hill-hammersmith 2tph wimbledon-high street ken 4tph wimbledon-edgware road-whitechapel 2tph wimbledon-edgware road-upminster 2tph olympia-edgware road-upminster 4tph ealing broadway-tower hill 2tph ealing broadway-tower hill-barking 2tph richmond-tower hill 2tph richmond-tower hill-whitechapel 2tph richmond-tower hill-barking 8tph edgware road-tower hill-upminster to give: - ham----8---edg---16 | \ 16 \ | \ oly hsk ls | | |\ 6 10 8 8 8 \ / \ / \ eb-6-tg-12--ec-20-gr-28-t-14-ae-22-w-16-b-12-u / / 6 12 | | rich wim richmond/ealing broadway-barking line1 green hammersmith-wimbledon/olympia line2 yellow olympia/wimbledon-edgware road-upminster line3 pink edgware road-upminster line4 bright green This gives extra trains to olympia, that go further, and keep the current service levels about the same, cept a 2tph increase from earl's court to whitechapel (if this bit of line doesn't cope then olympia-high street ken shuttles could replace half of the hammersmith to olympia service) and a 2tph increase from high street ken to edgware road, where the line should cope. Termini would also have the same number of trains terminating, except olympia and whitechapel, receiving an extra 2tph terminating. line 1 and line 4 could be shown as one line, called the District Line (for obvious reasons), though if the District was split on the diagram then River line for line 1 and Bazalgette (bloke that made the sewage system) line for line 4. Line 2 and 3 are hard to name, as what could you call them without causing confusion? "Hammersmith, City and Wimbledon line"? a bit of a mouthful, as is "Wimbledon and Barking" tbh. One word names are nice and easy, maybe named after a person. any ideas on what to call them? Simon |
district, circle and hammersmith and city lines - reorganisationidea
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district, circle and hammersmith and city lines - reorganisation idea
snip
Sounds good on paper, but the only way to prove that this would ever work is to calculate how many trains would pass through the following junctions at peak times: Praed Street Junction Gloucester Road Junction HSK Junction Baker Street Junction Aldgate Junction Minories Junction Aldgate East Junction If you come up with the same number of trains as the junctions currently handle, or less, send it to TfL. If you come up with more, scrap it. |
district, circle and hammersmith and city lines - reorganisation idea
simon wrote: 4tph wimbledon-edgware road-whitechapel 2tph wimbledon-edgware road-upminster 2tph olympia-edgware road-upminster 8tph edgware road-tower hill-upminster Don't forget all of these would need to be 'C' stock which has a reduced capacity compared to 'D' stock. (and are there enough 'C' trains?) |
district, circle and hammersmith and city lines - reorganisation idea
simon wrote:
I propose these services: 4tph olympia-tower hill-hammersmith 4tph wimbledon-tower hill-hammersmith 2tph wimbledon-high street ken 4tph wimbledon-edgware road-whitechapel 2tph wimbledon-edgware road-upminster 2tph olympia-edgware road-upminster 4tph ealing broadway-tower hill 2tph ealing broadway-tower hill-barking 2tph richmond-tower hill 2tph richmond-tower hill-whitechapel 2tph richmond-tower hill-barking 8tph edgware road-tower hill-upminster Yeah, it's nice to see someone thinking about how things could be improved, but as has already been mentioned, a lot more C stocks would be required than are available! Basically, any of the services via Edgware Road would have to be C stock, as the D stocks are too long to fit in the platforms (and I believe they scrape the platforms!). I think there's also a restriction on C stocks going any further east than Barking, although I'm not sure of the reasons. Then you'd also have the problem of training the drivers of the relevant depots to learn the new parts, for example as a District man, I don't sign the route between Edgware Road and Aldgate via Kings Cross, and an Edgware Road driver doesn't sign the road west of Gloucester Road (including Earl's Court). Maybe such a re-organisation will come about when we eventually get a generic stock on the sub-surface lines? |
district, circle and hammersmith and city lines - reorganisationidea
(snip the idea)
Interesting idea. My personal quibble is the loss of direct trains from South Kensington/Gloucester Road to Baker Street. You also have 2 extra trains per hour crossing on the flat at the key junctions (Edgware Road, Gloucester Road, Aldgate East). That may be a problem at Gloucester Road Junction in particular unless either inner "Circles" (i.e. Edgware Rd - Tower Hill - Upminsters) were timed to approach Gloucester Road station at the same time outer "Circles" were leaving for HSK - otherwise one or the other would get delayed by or would delay eastbound "Districts" heading for Victoria. Reinstating the second eastbound platform at Gloucester Road would help as it would allow inner "Circles" to arrive at Gloucester Road simultaneously with eastbound "Districts", with departures regulated from there. Unfortunately such a platform reinstatement would require expensive reconstruction (narrowing) of the island platform at Gloucester Road. -- Dave Arquati Imperial College, SW7 www.alwaystouchout.com - Transport projects in London |
district, circle and hammersmith and city lines - reorganisation idea
DistrictDriver wrote:
Basically, any of the services via Edgware Road would have to be C stock, as the D stocks are too long to fit in the platforms (and I believe they scrape the platforms!). I think there's also a restriction on C stocks going any further east than Barking, although I'm not sure of the reasons. UIVMM it's because C stock can't go as fast as D stock, so would cause delays. |
district, circle and hammersmith and city lines - reorganisation idea
Aidan Stanger wrote:
DistrictDriver wrote: Basically, any of the services via Edgware Road would have to be C stock, as the D stocks are too long to fit in the platforms (and I believe they scrape the platforms!). I think there's also a restriction on C stocks going any further east than Barking, although I'm not sure of the reasons. UIVMM it's because C stock can't go as fast as D stock, so would cause delays. I always thought it was a gauging issue at Dagenham East - some part of the C stock kept getting smacked by a platform edging stone or railing. I've seen C stock DMs with Upminster on their dest. blinds, so they've definitely been there in the past. |
district, circle and hammersmith and city lines - reorganisationidea
On 13 Feb 2005, TheOneKEA wrote:
Aidan Stanger wrote: DistrictDriver wrote: Basically, any of the services via Edgware Road would have to be C stock, as the D stocks are too long to fit in the platforms (and I believe they scrape the platforms!). I think there's also a restriction on C stocks going any further east than Barking, although I'm not sure of the reasons. UIVMM it's because C stock can't go as fast as D stock, so would cause delays. I always thought it was a gauging issue at Dagenham East - some part of the C stock kept getting smacked by a platform edging stone or railing. I've seen C stock DMs with Upminster on their dest. blinds, so they've definitely been there in the past. We went over this a few weeks ago (search for "dull questions about loading gauge"): once upon a time, there were speed restrictions on C stock out there, due to some sort of gauge business. However, (a) trains would have to slow down for the station starter anyway (no idea what that means!) and (b) the business is now taken care of. No idea about the speed thing, though. A stock to Upminster, is what i say! tom -- Restate my assumptions |
district, circle and hammersmith and city lines - reorganisation idea
Tom Anderson wrote:
We went over this a few weeks ago (search for "dull questions about loading gauge"): once upon a time, there were speed restrictions on C stock out there, due to some sort of gauge business. However, (a) trains would have to slow down for the station starter anyway (no idea what that means!) and (b) the business is now taken care of. (a) is probably in reference to an approach-released station starter; in a controlled area like Dagenham East (FG), the interlocking is probably designed to clear the relevant starter after the platform track circuit has been occupied for a short period. In an auto area, a timer circuit is used. |
district, circle and hammersmith and city lines - reorganisation idea
In article ,
Tom Anderson writes However, (a) trains would have to slow down for the station starter anyway (no idea what that means!) The station starter is the signal at the departure end of the platform; while it is red, the train can't (legally) start away. On LU the signalling is designed on the assumption that all trains will be stopping at every station[*]. If a train runs through a station at speed and passes a red signal, it is possible that the trip stops will not stop it in time to prevent an accident [+]. Therefore drivers are instructed to slow to 5mph (or in some places 10mph) when running non-stop through a station. [*] There are some specific exceptions, such as Turnham Green on the Piccadilly, and the signalling in these places is altered accordingly. [+] In general, a signal can only turn green if a train hitting the train stop of the following red signal *at line speed* will be stopped before the point of actual danger (e.g. another train). Designing for the maximum possible speed of all trains would be unduly restrictive, so designing to the speed limit of the line is a sensible compromise. -- Clive D.W. Feather | Home: Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org Fax: +44 870 051 9937 | Work: Please reply to the Reply-To address, which is: |
district, circle and hammersmith and city lines - reorganisation idea
Clive D. W. Feather wrote:
[*] There are some specific exceptions, such as Turnham Green on the Piccadilly, and the signalling in these places is altered accordingly. In the case of Turnham Green, both lines do have home signals - the EB line's homes are A631^A and A631^B, and the WB's are A630^A and A630^B. Would the overlaps on these homes simply be longer than usual, to allow a train to alternately stop or pass through at linespeed? [+] In general, a signal can only turn green if a train hitting the train stop of the following red signal *at line speed* will be stopped before the point of actual danger (e.g. another train). Designing for the maximum possible speed of all trains would be unduly restrictive, so designing to the speed limit of the line is a sensible compromise. This doesn't make much sense. Are you saying that if a train passes a red signal at linespeed or higher and gets tripped, the signal in rear could change to green if the entire train manages to exit that signal's overlap? |
district, circle and hammersmith and city lines - reorganisation idea
TheOneKEA wrote:
Clive D. W. Feather wrote: snip [+] In general, a signal can only turn green if a train hitting the train stop of the following red signal *at line speed* will be stopped before the point of actual danger (e.g. another train). Designing for the maximum possible speed of all trains would be unduly restrictive, so designing to the speed limit of the line is a sensible compromise. This doesn't make much sense. Are you saying that if a train passes a red signal at linespeed or higher and gets tripped, the signal in rear could change to green if the entire train manages to exit that signal's overlap? A signal is controlled by all the track circuits between it and the end of the next signal's overlap. Therefore a signal will show red whilst there is an occupied track circuit either between it and the next signal or in the next signal's overlap. -- Cheers for now, John from Harrow, Middx remove spamnocars to reply |
district, circle and hammersmith and city lines - reorganisation idea
In article . com,
TheOneKEA writes [*] There are some specific exceptions, such as Turnham Green on the Piccadilly, and the signalling in these places is altered accordingly. In the case of Turnham Green, both lines do have home signals - the EB line's homes are A631^A and A631^B, and the WB's are A630^A and A630^B. Would the overlaps on these homes simply be longer than usual, to allow a train to alternately stop or pass through at linespeed? Yes. Just as with a signal between stations. The overriding principle is that a train stop hit at line speed should stop the train before the point of danger. [+] In general, a signal can only turn green if a train hitting the train stop of the following red signal *at line speed* will be stopped before the point of actual danger (e.g. another train). This doesn't make much sense. Are you saying that if a train passes a red signal at linespeed or higher and gets tripped, the signal in rear could change to green if the entire train manages to exit that signal's overlap? Yes. But, in that case, the situation will still be protected. Um, let's see: |-O 1 |-O 2 |-O 3 |-O 4 |-O 5 -+---A---+---B---+---C---+---D---+---E---+---F---+---G---+---H---+---I- Let's assume that braking distance from line speed is 1.4 times the signal spacing. So: 1 is red if A, B, C, D, or E is occupied 2 is red if C, D, E, F, or G is occupied 3 is red if E, F, G, H, or I is occupied etc. Suppose there's an obstruction at F. Signal 3 will be red because it's within its block. Signal 2 will be red because a train tripped at signal 3 won't stop until somewhere in G. Signal 1 can be green because a train tripped at signal 2 from line speed will stop somewhere in E. Now suppose a train runs past signal 1 at well over line speed and hits the trip at signal 2. Signal 1 will be red at this point because the train is occupying B and C. The train brakes but, because it was speeding, it doesn't stop until somewhere in F. As the rear of the train passes the E-F boundary signal 1 will revert to green *but* the situation is still protected by signal 2 at red. Clear? Or have I answered the wrong question? -- Clive D.W. Feather | Home: Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org Fax: +44 870 051 9937 | Work: Please reply to the Reply-To address, which is: |
district, circle and hammersmith and city lines - reorganisation idea
Clive D. W. Feather wrote:
In article . com, TheOneKEA writes In the case of Turnham Green, both lines do have home signals - the EB line's homes are A631^A and A631^B, and the WB's are A630^A and A630^B. Would the overlaps on these homes simply be longer than usual, to allow a train to alternately stop or pass through at linespeed? Yes. Just as with a signal between stations. The overriding principle is that a train stop hit at line speed should stop the train before the point of danger. Thanks, that was what I thought. This doesn't make much sense. Are you saying that if a train passes a red signal at linespeed or higher and gets tripped, the signal in rear could change to green if the entire train manages to exit that signal's overlap? Yes. But, in that case, the situation will still be protected. Um, let's see: snip Clear? Or have I answered the wrong question? I understand now. But it doesn't seem sensible to place the signals that close together, or only hold one signal in rear of the signal protecting an obstruction at danger. |
district, circle and hammersmith and city lines - reorganisation idea
In article . com,
TheOneKEA writes I understand now. But it doesn't seem sensible to place the signals that close together, Signal spacing is chosen to meet various requirements, including maximum throughput of trains. For example, on LU there are usually several signals approaching a station, because this allows a train to draw up close as the previous train departs. This is *better* than spacing the signals further apart, but could mean that there are four or five red signals behind a train under some circumstances. or only hold one signal in rear of the signal protecting an obstruction at danger. Why? If one red signal can protect the obstruction, what's the need for more? -- Clive D.W. Feather | Home: Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org Fax: +44 870 051 9937 | Work: Please reply to the Reply-To address, which is: |
district, circle and hammersmith and city lines - reorganisation idea
Clive D. W. Feather wrote:
Signal spacing is chosen to meet various requirements, including maximum throughput of trains. For example, on LU there are usually several signals approaching a station, because this allows a train to draw up close as the previous train departs. This is *better* than spacing the signals further apart, but could mean that there are four or five red signals behind a train under some circumstances. I've seen numerous examples of this around the system and guessed that the rationale was something similar to what you've just stated. or only hold one signal in rear of the signal protecting an obstruction at danger. Why? If one red signal can protect the obstruction, what's the need for more? You just showed that under certain circumstances, one signal is not enough to protect an obstruction (or at least I think you did...) |
district, circle and hammersmith and city lines - reorganisation idea
TheOneKEA wrote:
Clive D. W. Feather wrote: Signal spacing is chosen to meet various requirements, including maximum throughput of trains. For example, on LU there are usually several signals approaching a station, because this allows a train to draw up close as the previous train departs. This is *better* than spacing the signals further apart, but could mean that there are four or five red signals behind a train under some circumstances. I've seen numerous examples of this around the system and guessed that the rationale was something similar to what you've just stated. or only hold one signal in rear of the signal protecting an obstruction at danger. Why? If one red signal can protect the obstruction, what's the need for more? You just showed that under certain circumstances, one signal is not enough to protect an obstruction (or at least I think you did...) You only need one signal to proect an obstruction. Additional signals mean that a following train can enter a platform more closely behind the one departing whilst still maintaining a safe distance between them. |
district, circle and hammersmith and city lines - reorganisation idea
In article .com,
TheOneKEA writes Why? If one red signal can protect the obstruction, what's the need for more? You just showed that under certain circumstances, one signal is not enough to protect an obstruction (or at least I think you did...) Um, no. You have to make *some* assumptions when designing a signalling system. The ones LU make a (1) train stops will stop trains in the design distance; (2) trains won't be exceeding the speed limit at the point they pass a red signal in the worst situation. Within those assumptions, one signal is all that's needed. There may be two or more, but only one is doing the protecting. -- Clive D.W. Feather | Home: Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org Fax: +44 870 051 9937 | Work: Please reply to the Reply-To address, which is: |
district, circle and hammersmith and city lines - reorganisation idea
In message . com,
TheOneKEA writes [*] There are some specific exceptions, such as Turnham Green on the Piccadilly, and the signalling in these places is altered accordingly. In the case of Turnham Green, both lines do have home signals - the EB line's homes are A631^A and A631^B, and the WB's are A630^A and A630^B. Would the overlaps on these homes simply be longer than usual, to allow a train to alternately stop or pass through at linespeed? Yes. A Non-stopping Picc train doesn't have any speed restriction on the fast lines through Turnham Green. The normal 'rule' is 5 mph at a station starter. However, if we (the Picc) are run down the local (District) line from Acton to Hammersmith, we can pass the starters at 25 mph., so there must be some adjustments of the overlaps there too. -- Steve Fitzgerald has now left the building. You will find him in London's Docklands, E16, UK (please use the reply to address for email) |
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