Jubilee Line Terminus Dwelling Times

[Deleted]

Hi all.
On all of the other tube lines (Bakerloo, Central, Circle, District etc.) the trains tend to spend at least 5-6 minutes at the terminuses and often up to 11-12. However on the Jubilee Line this doesn't seem to be the case. I've never actually caught the train to Stanmore but certainly at Stratford, the trains stop for 4 minutes maximum. Is this due to a lack of terminus platforms so the Jubilee Line trains can't stop for more than 4 minutes before the next train comes along? (Although on the Jubilee Line this would have to mean services of 35-45tph to warrant this).

Is there any particular reason that the Jubilee Line services don't dwell for so long at the terminuses? Or is it something that all new lines are doing as to maintain a rapid transit system from all stations?

[Deleted]

Its all to do with Capacity. Visit Brixton during the peak; trains leave about every 2.5 minutes so with only two platforms, trains only have about 4 minutes dwell time.

At Stanmore, Jubilee trains sit for about 8 minutes.

[Deep Level]

I guess Stanmore can have longer dwelling times as not as many trains terminate there than at Stratford with other western termini at Willesden Green, Wembley Park & West Hamstead, where the only Eastern Termini are at Stratford & North Greenwich which is hardly used (well the last time I checked).

Has platform 3 at Stanmore opened yet?

[mrfs42]

May 23, 2011 18:13:00 GMT @martello736 said:

the trains stop for 4 minutes maximum.

Be careful how you measure this maximum; remember too that the platforms at Stratford have different transit times from the previous timing point.

Looking at the WTT, I would say that 4 mins whilst on paper the minimum time for an unassisted reversal, they are actually more the exception at Stratford than the rule: at a very quick glance 5¾ - 6 mins would seem to be the most frequent terminal stand time during evening busy, morning busy nearer 6¼ - 7½ mins.

[Ben]

Is it a reasonable approximation that a terminal platform on a metro line can handle a maximum of 15tph then? Assuming that the opperation is unassisted and that the driver has no longer than 500' to walk between cabs?

Terminal capacity and opperation seems a fascinating science.

[mrfs42]

May 24, 2011 11:28:32 GMT @engineer said:

There are many variables involved - Layout, Signalling, manual/ATO, arrangements for changing ends and assumptions for crewing, passenger loading and crowding, etc....

Indeed - don't forget the width and number of the door openings too....

[Deleted]

Interesting.

Thanks for all of the opinions.

As for the platform capacity, can a typic terminus platform handle 15tph? Surely this would mean 3 minutes stopped in the station and 1 minute changeover or something like that.

[mrfs42]

Please do.

[slugabed]

To Engineer:
Don't worry (from a reader's perspective) about long posts.
These last few posts on this thread have explained in a clear and concise manner,a complicated subject which most passengers never even consider but makes the running of a railway possible.
As a user of the Underground,rather than one working on the railway,I have found your posts really informative and easy to follow,and will certainly lead me to look out for things next time I use a terminus...
Keep up the good work!

[causton]

Concise? Not sure about that one but a very interesting read, there is a whole lot more than I had originally considered and I guess it is simple once you think about it, but there IS a lot to think about!

[Deleted]

Thanks engineer for all of the information.

So what would you say the minimum practical stopping time is? I mean ultimately the trains could stop at the station for as little as 20 seconds which would give as you said a frequency of around 24tph but what is the time that is most suitable and most likely to work on the tube?

[Deleted]

Thanks engineer. It's interesting that they use the 2 driver per platform option on W&C line in the rush. Not sure about other lines but I know the Bakerloo at E&C takes a lot longer to turn around. So as a layman, it's great reading a in depth expert analysis.

[Chris M]

May 25, 2011 17:59:02 GMT @martello736 said:

Thanks engineer for all of the information.

So what would you say the minimum practical stopping time is? I mean ultimately the trains could stop at the station for as little as 20 seconds which would give as you said a frequency of around 24tph but what is the time that is most suitable and most likely to work on the tube?

I'm about as far from an expert as you can get, but I suspect that there will be no single answer. It will depend on things like the configuration of the stocks (a C stock with more doors and wider gangways is much faster to empty than an A stock), the volume of people entering and exiting (a busy terminus like Stratford JLE will require more time than a quieter one like Mill Hill East), the nature of the people entering and exiting (seasoned commuters at Bank W&C will require less time than heavily encumbered tourists at Heathrow) and possibly even the position of the platform entrance and exit relative to the train (exit and entrance in the same place will cause congestion, having them at or beyond one end of the train will cause uneven loadings on the train - see Stratford Jubilee for example), although there isn't much variation in the position of these at termini across LU (Epping platform 2, High Barnet platform 2, and the Heathrow stations are the only ones I can think of that aren't at or beyond the end of the train).

[Deleted]

May 25, 2011 19:02:57 GMT Chris M said:

May 25, 2011 17:59:02 GMT @martello736 said:

Thanks engineer for all of the information.

So what would you say the minimum practical stopping time is? I mean ultimately the trains could stop at the station for as little as 20 seconds which would give as you said a frequency of around 24tph but what is the time that is most suitable and most likely to work on the tube?

I'm about as far from an expert as you can get, but I suspect that there will be no single answer. It will depend on things like the configuration of the stocks (a C stock with more doors and wider gangways is much faster to empty than an A stock), the volume of people entering and exiting (a busy terminus like Stratford JLE will require more time than a quieter one like Mill Hill East), the nature of the people entering and exiting (seasoned commuters at Bank W&C will require less time than heavily encumbered tourists at Heathrow) and possibly even the position of the platform entrance and exit relative to the train (exit and entrance in the same place will cause congestion, having them at or beyond one end of the train will cause uneven loadings on the train - see Stratford Jubilee for example), although there isn't much variation in the position of these at termini across LU (Epping platform 2, High Barnet platform 2, and the Heathrow stations are the only ones I can think of that aren't at or beyond the end of the train).

Thanks. Ok though, lets just say that we have a train with 3 sets of 2.5m doors per car (wide!) The terminus has 4 large entrances / exits spread out along the platform so that all entrants and exiters are evenly spread out. The train is wide and the gangways are large. The train has fast acceleration and a maximum operating speed of 70mph. And lets just throw the spanish solution in (doors opening on both sides of the train) for good luck. What would the time be then?

[mrfs42]

May 25, 2011 17:59:02 GMT @martello736 said:

Thanks engineer for all of the information.

So what would you say the minimum practical stopping time is? I mean ultimately the trains could stop at the station for as little as 20 seconds which would give as you said a frequency of around 24tph but what is the time that is most suitable and most likely to work on the tube?

Fastest station stop I have ever timed (and then emailed to myself from my phone) was 16. 2 seconds.

[norbitonflyer]

May 24, 2011 23:04:52 GMT @engineer said:

Stepping back off one platform

All that's just been described might be achievable in a dwell of 1 1/2 or two minutes,

Positively snail-like! I timed the Drain this evening at Bank - wheels stopped to wheels start was 51 seconds - would have been less but we had to wait for the signal to clear.

A link from a thread back in August showed a standard scissors layout terminal in Japan turning two trains round every 3m30., which equates to 34 tph.

Bank has, I think, always had stepping back in the morning peak because an entire trainload of people (unlike any other line, no-one can have got off at any intermediate stations!) are heading foir the exit beyond the buffer stops and the driver has, salmon-like, to swim against this flow to change ends. With stepping back, he can let the surge die down, safe in the knowledge that his predecessor will take the train out.

It is quite normal, if you boarded at the back at Waterloo, for the train to have left before you have walked half its length. The driver, going against the flow, will have made even less progress.

[Deleted]

So 34tph, wow that is a lot! But surely it is more practical to only allow a train around every 5-6 minutes on each platform for delay prevention and a bit of backup should anything go wrong.

[tubeprune]

engineer has done an excellent job of explaining how the turnround at a terminus works. I can add that using the two platforms at Brixton, using 1967 Tube Stock, you can get a 126 second headway, including a small allowance for variations. This gives a 28.5 trains per hour throughput and it is the pinch point for the whole line. I expect that the new signalling and new stock will reduce this to less than 120s. Then the pinch points will be the dwell times at places like Victoria and Kings Cross.

[Deleted]

Jun 5, 2011 15:49:37 GMT tubeprune said:

engineer has done an excellent job of explaining how the turnround at a terminus works. I can add that using the two platforms at Brixton, using 1967 Tube Stock, you can get a 126 second headway, including a small allowance for variations. This gives a 28.5 trains per hour throughput and it is the pinch point for the whole line. I expect that the new signalling and new stock will reduce this to less than 120s. Then the pinch points will be the dwell times at places like Victoria and Kings Cross.

Adding to this thread, I would state that the realistic max capacity of a 2 track terminus with scissors crossover is typically platform re-occupation time + 30 secs. The 30secs allows for door closing time, and operating margin. Brixton fits this scenario perfectly as the platform re-occupation time is/was 96secs, and the headway is 126secs. For the post upgrade planned 33tph to occur, I would expect that the platform-reoccupation time would need to be approx. 80secs.

The examples earlier in thread from Hong Kong are interesting. Chai Wan on the MTR Island Line now "only" handles 120 sec headways with 182m trains. The very long door closing sequence (trilingual door closing announcements and lots of beeping) starts before the inbound train has cleared the crossover. I was unable to see if any countdown timers or other methods initiated this time saving action.

[trivran]

Say you had a Four-Track Terminus, Two Platforms directly facing out and two platforms facing in on a balloon loop round onto the outward track. Using norbitonflyer's 51 second time rounded up to 1 minute, that's 60tph on one platform and 240tph for the whole station. Wishful thinking..

[Deleted]

For whoever it was that asked - yes the 3rd platform at Stanmore is in use now TBTC is in control of the whole line. The timetable was modified (WTT10) to make use of it.

WTT11 coming very soon, so the 4 min dwell will be less as stepping back will be used at Stratford

[jardine01]

Is the new Jubilee line Timetable in operation yet?

[Deleted]

The new TT is indeed in operation, aswell as Stanmore platform 3, you can tell because the trains are really flying along now.

[mcmaddog]

Aug 1, 2011 14:33:47 GMT @delboy200 said:

The new TT is indeed in operation, aswell as Stanmore platform 3, you can tell because the trains are really flying along now.

Was that today or yesterday? I was on it yesterday afternoon and it see-sawed on/off power all the way from Baker Street to Finchley Road.

[DrOne]

I travelled Canada Water - Bond Street today and the ride was great. Apart from Canada Water-Bermondsey, throughtout the train seemed to easily reach and maintain good speed and stopped very crisply. I need to try the rest of the line but today certainly felt more efficient. Hope it is sustained.

[trivran]

Has anyone ever been on it when thedriver has been coasting?

[jardine01]

I traveled from Westminister to Green Park and It is much faster apart from Baker street to St Johns Wood were it was going quite slowly allot of on off power. Are these trains quicker of the mark now with the new timetable?