Longer dwell-times on extension stations?

[Deleted]

Is it me or do the Jubilee Line trains seem to remain longer at stations on the extension than on the old part of the line?

Is this the case and if so, I wonder why?

[Deleted]

Because they're busier?

[astock5000]

Could it be something to do with the doors on the platforms?

[Deleted]

Could be, although I don't think they would affect dwell time, might affect the overall journey time without ATO since the drivers have to creep up on them.

[Deleted]

Dec 30, 2008 18:35:10 GMT @tom747 said:

Because they're busier?

I've noticed this even at quiter times of the day.

[Deleted]

Dec 30, 2008 18:37:02 GMT astock5000 said:

Could it be something to do with the doors on the platforms?

I've wondered this, myself, but can't see what difference it ought to make.

[Deleted]

Dec 30, 2008 18:06:56 GMT @tubeflight said:

Is it me or do the Jubilee Line trains seem to remain longer at stations on the extension than on the old part of the line?

Is this the case and if so, I wonder why?

As I driver I believe it is you. Depending on how early I might be running will then depend on how long I am waiting at particular stations for a green signal. Simple.

[mrfs42]

Jan 12, 2009 1:52:04 GMT @peddoors said:

Dec 30, 2008 18:06:56 GMT @tubeflight said:

Is it me or do the Jubilee Line trains seem to remain longer at stations on the extension than on the old part of the line?

Is this the case and if so, I wonder why?

As I driver I believe it is you. Depending on how early I might be running will then depend on how long I am waiting at particular stations for a green signal. Simple.

Looking at WTT 6 there *is* a clear difference in booked station dwell times. WTT 6 (20/5/01) was the last Jubilee to have dwell times published in the WTT preamble - I've got some scanning to do this morning. I will scan and upload the relevant bit of information - to chart it would be too much of a faff for my little mind. ;D

Suggested dwell time info from WTT 6 - I'm not sure if this is now current as mentioned above - Clickety click, make of this what you will.

HTH.

[Ben]

The two longest times I can see on that list are 45 seconds, at Bond Street and Green Park. Myth busted, perhaps! I can only shudder to think what those times would have been if the 83s had soldiered on.

[Deleted]

Jan 12, 2009 9:42:32 GMT mrfs42 said:

Suggested dwell time info from WTT 6 - I'm not sure if this is now current as mentioned above - Clickety click, make of this what you will.

HTH.

Just had a look at that chart and found the dwell times on the extension quite strange and obviously worked out differently. On the old section all dwell times are all rounded 30,35,40 seconds etc. On the extension stations have 24, 27, 29 and 31 second dwell times.

[21146]

I thought it was the inadequate signalling, installed at the last minute for 2000, which causes blocking back.

[Tom]

It shouldn't be, as a lot of mods were done to improve capacity.

[21146]

Well the service interval on the extension certainly doesn't seem to compare with, say, the Central or Piccadilly Lines

[Tom]

I didn't say that the mods were intended to increase the JLE service interval to one comparable with the Central or Piccadilly Lines, merely that they were designed to increase capacity. This they did, from (IIRC) 20 to 24 tph.

[citysig]

Jan 26, 2009 4:01:02 GMT @jim said:

Just had a look at that chart and found the dwell times on the extension quite strange and obviously worked out differently. On the old section all dwell times are all rounded 30,35,40 seconds etc. On the extension stations have 24, 27, 29 and 31 second dwell times.

This is a theme that has run through the extension of the line. On the old side, when the signalling computer looks at late-running (or is interrogated for it at a later date) the time is rounded to half-minute intervals.

On the extension, they have the ability to see late-running down to the exact second.

When it comes to doing the number-crunching for how many trains they have run through the line in the peak (to satisfy those at Canary Wharf) it's shown as "every minute or so" on the old side, but precise timings are shown on the extension.

I've no doubt that when the old side is finally put into Neasden later this year (beginning of next-ish) all of the dwell times / headways / late-running calculations will be shown to the exact second.

I doubt very few trains actually achieve the exact published dwell time, so it does make it a pretty pointless exercise, but no doubt someone somewhere has the job of working out which trains did or did not acheive it. Keeps that someone in work I suppose, but it's hardly the way to run a railway.

[Deleted]

Jan 26, 2009 18:05:33 GMT @21146 said:

I thought it was the inadequate signalling, installed at the last minute for 2000, which causes blocking back.

a friend said that they used some parts from the old central line signalling, anybody know if that is true?

[Deleted]

Jan 27, 2009 16:21:11 GMT @delboy200 said:

Jan 26, 2009 18:05:33 GMT @21146 said:

I thought it was the inadequate signalling, installed at the last minute for 2000, which causes blocking back.

a friend said that they used some parts from the old central line signalling, anybody know if that is true?

Didnt they used part of the old signalling for the Jubilee Line extension when they abandoned moving block?

[Tom]

It's true - the trainstops are all modified HO trainstops with manual lubrication and a different wiring connection.

They were removed from the Central line, refurbished and modified with a litton socket to replace the old 'snake' cable, and installed on the JLE.

No-one else has used a self-oiler for years!

[Deleted]

Jan 27, 2009 15:15:18 GMT @citysig said:

I've no doubt that when the old side is finally put into Neasden later this year (beginning of next-ish) all of the dwell times / headways / late-running calculations will be shown to the exact second.

Will the timetables then be created to 1 second accuracy?

[mrfs42]

Jan 28, 2009 10:46:30 GMT @stephenk said:

Jan 27, 2009 15:15:18 GMT @citysig said:

I've no doubt that when the old side is finally put into Neasden later this year (beginning of next-ish) all of the dwell times / headways / late-running calculations will be shown to the exact second.

Will the timetables then be created to 1 second accuracy?

Or will it be like Wood Lane, where the workstations carry the basic WTT loaded into their area of purview and any necessary adjustments to be/being made by the regulator are shown in 1 second increments on the workstation, although the WTT is only printed to ¼ minute accuracy (like the Drain even with ∇ at both ends)?

[citysig]

Jan 28, 2009 10:46:30 GMT @stephenk said:

Will the timetables then be created to 1 second accuracy?

Jan 28, 2009 11:13:49 GMT mrfs42 said:

Or will it be like Wood Lane, where the workstations carry the basic WTT loaded into their area of purview and any necessary adjustments to be/being made by the regulator are shown in 1 second increments on the workstation, although the WTT is only printed to ¼ minute accuracy (like the Drain even with ∇ at both ends)?

It could be either, but I fear stephenk may be closer if the second-watching they do at present is anything to go by.

Can you seriously imagine a scenario where a train is consistently 3.5 seconds late at each station, and the driver is hauled over the coals to find out why he/she did not "perform" at each station. Or the train is taken out of service for a "download" of data to check why it could not achieve its booked running time.

[d7666]

Can you seriously imagine a scenario where a train is consistently 3.5 seconds late at each station,

Generic Seltrac S40 has features that will attempt to bring a train with that sort of delay back on to timetabled path without human intervention. Not only that train, but anything behind, and ahead, that would be impacted upon.

However, as with all software, generic features are not necessarily contained in the customer package, while other non-standard features may be added.

I will endeavour to find out if JNUP S40 has this feature enabled, and if so, within what bounds.

--
Nick

[DrOne]

Jan 26, 2009 18:29:04 GMT @21146 said:

Well the service interval on the extension certainly doesn't seem to compare with, say, the Central or Piccadilly Lines

When things are running well doens't the Jub run 24tph? Isn't this the same as the current peak Picc frequency? I do agree that the Picc always feels more frequent when I have to use both lines. Maybe the difference lies in the off-peak frequencies.