Victoria line slower that before !!

[vic09]

Hello this is my first post.
There was something that was bugging me for ages, and I just wanted to know why. On the Victoria line, I used to love the section between Green park and Oxford Circus Northbound, it felt like you was flying along that track really fast. It also pulled in to Oxford circus really fast. Now theyve put in this new signalling it now comes in really slow like at Victoria. Also it now takes longer to get from station to station. Does
Anybody know why??

[racka]

It is a speed restriction for train headway purposes. The contract is performance based, which means in basic terms there is a trade off to be done between interstation runtimes (the time for a train to get from station A to station B) and platform re-occupation times (the time between train A starting from a platform to train B becoming stationary at the same platform).

Generally, increasing interstation run times (trains running slower), improves the platform re-occupation time, since slower trains can run closer together. Achieving good re-occupation times at these critical areas of the line is important if you want to achieve a good performance 'score'. Unfortunately, this sometimes has the side effect of slower interstation run times (trains running slower).

Hope that answers your question.

[vic09]

Thanks for that do you know if it is permant or just temporary

It's all driven by scores. I've heard a legend, that once upon a time, railways moved people really fast, and moving people faster would help them..

[xercesfobe]

Has this anything to do regenerative breaking and load balancing? -By this I mean one train slowing and feeding power back as the other is taking power and accelerating?

XF

[londonstuff]

Mar 16, 2012 10:14:46 GMT racka said:

It is a speed restriction for train headway purposes. The contract is performance based, which means in basic terms there is a trade off to be done between interstation runtimes (the time for a train to get from station A to station B) and platform re-occupation times (the time between train A starting from a platform to train B becoming stationary at the same platform).

Generally, increasing interstation run times (trains running slower), improves the platform re-occupation time, since slower trains can run closer together. Achieving good re-occupation times at these critical areas of the line is important if you want to achieve a good performance 'score'. Unfortunately, this sometimes has the side effect of slower interstation run times (trains running slower).

Hope that answers your question.

To a non-signal technician the new Victoria line signalling system seems very strange. I've mentioned on here before about the headwall signals always being red and how this must slow things down, only to be told be those in the know that it won't.

However, I beg to disagree - I've been on the Vic a few times in the last couple of weeks, in peaks and out of peaks, on crowded trains and empty, northbound and southbound and often with 3 minute gaps between trains (I mention this last point only because the signalling presumably is then not held up by a train too closely in front).

My observations are thus:
The red aspect at each headwall remain at danger for much longer than it takes passengers to alight and board the majority of the time, leading to increased dwells. Often this is the case for over a minute or two. I was held at KX southbound the other day, with no disruption or any trains close ahead for about three minutes. This has happened several times and seems to be for no good reason.

The blue aspects also seem to be very arbitrary with them appearing at some stations and not others, including some stations that don't even seem to have a blue aspect (Warren Street NB I think, but not sure).

In general the trains do seem to be slower in the central area of the line but quicker in the stretches, e.g. Finsbury to H&Islington.

I'm also absolutely surprised that, according to Diamond Geezer today, the new timetable isn't going to be implemented until March 2012. I know these things take time, but surely...

The work has been ongoing with the Vic now since, what, 2008? 2009? with the early closures, etc. and from a casual viewpoint, apart from the new trains there doesn't seem to have been any measurable improvement, not least in journey time. I'm certainly not trying to be negative and would love those in the know - Dan and Racka? - to tell me that I'm wrong.

At least the victoria line drives at a set speed not like the Jubilee line! Maybe once the whole line is under the new Distance to go Signaling it might be allot quicker?

[vic09]

Yes good point I really do think that the Victoria is faster than the jubilee. I've allways said that the peds act as an illusion and make you think it's faster than what's its going. Once it gets outside thats it, it's like a snail.

[mrfs42]

Mar 16, 2012 21:49:23 GMT londonstuff said:

To a non-signal technician the new Victoria line signalling system seems very strange. I've mentioned on here before about the headwall signals always being red and how this must slow things down, only to be told be those in the know that it won't.

(takes a break from packing non-UndergrounD WTTs) - I recall that the current WTT has running and dwell times based on the previous WTT "allowing recovery while the new assets are bedding in".

Mar 16, 2012 21:49:23 GMT londonstuff said:

My observations are thus:
The red aspect at each headwall remain at danger for much longer than it takes passengers to alight and board the majority of the time, leading to increased dwells. Often this is the case for over a minute or two. I was held at KX southbound the other day, with no disruption or any trains close ahead for about three minutes. This has happened several times and seems to be for no good reason.

Well, you know what my thoughts are.. If the trains are running to a former set of intermediate times and are now a lot more nippy given that the regen can be switched on with the old girls being sent out to grass, it is only natural that the dwell times seem longer - the trains simply get there quicker! I presume that the starters are still held to time and will clear to timetable (rather than have the regulator intervene for each and every one)

Mar 16, 2012 21:49:23 GMT londonstuff said:

The blue aspects also seem to be very arbitrary with them appearing at some stations and not others, including some stations that don't even seem to have a blue aspect (Warren Street NB I think, but not sure).

AFAIAA VWS 1425 (Warren St NB starter) *does* have a blue aspect; and as regards transition areas Pimlico SB starter (A394) will not have a blue aspect, as below there is still old-style signalling.

Mar 16, 2012 21:49:23 GMT londonstuff said:

In general the trains do seem to be slower in the central area of the line but quicker in the stretches, e.g. Finsbury to H&Islington.

Presumably that is a function of still running to old dwell times?

Mar 16, 2012 21:49:23 GMT londonstuff said:

I'm also absolutely surprised that, according to Diamond Geezer today, the new timetable isn't going to be implemented until March 2012. I know these things take time, but surely...

Having been very pleasantly surprised with the changes in Jubilee 11 compared to Jubilee 10, I await similar style developments on the Vic with interest.

..er.. don't you mean March 2013? Presumably that will allow for the new signalling to go to Brixton and then a suitable 'shakedown' period (washes mouth out with soap and water).

The Victoria is the best line in terms of speed and power of the trains.
I don't get why the Jubilee line is so slow outside? The Central goes full speed outside

[cityboy]

There's another Vic closure 30/01-01/04. Presumably this will upgrade the new signals all the way to Brixton. there's then another 06-07/05 which is for the signalling to the depot. From memory, some time after that, but also in May, the new timetable will come into play. Can someone with insider knowledge confirm?

Edit; I've just read that Tfl forecast a 16% decrease in journey times. This must in part come through higher speeds once the new timetable is introduced.

[Dstock7080]

New WTT34 scheduled to operate from 22 April.

[superteacher]

It's only relatively recently that the speed has been slowed from Green Park to Oxford Circus.

I don't buy this headway stuff though. Maybe in the peak when running a 30tph plus service, but 27tph off peak shouldn't require a slow down.

[Rich32]

Mar 16, 2012 23:03:51 GMT mrfs42 said:

Mar 16, 2012 21:49:23 GMT londonstuff said:

To a non-signal technician the new Victoria line signalling system seems very strange. I've mentioned on here before about the headwall signals always being red and how this must slow things down, only to be told be those in the know that it won't.

(takes a break from packing non-UndergrounD WTTs) - I recall that the current WTT has running and dwell times based on the previous WTT "allowing recovery while the new assets are bedding in".




Well, you know what my thoughts are.. If the trains are running to a former set of intermediate times and are now a lot more nippy given that the regen can be switched on with the old girls being sent out to grass, it is only natural that the dwell times seem longer - the trains simply get there quicker! I presume that the starters are still held to time and will clear to timetable (rather than have the regulator intervene for each and every one)

That from my observations is what is happening, although there are regulator interventions as observed, by quite a few red to green changes.

Blue aspects are at most signal posts on the converted parts (WAL to PIM), but not all - HBY n/b station starter being one example. The appearance of a blue aspect will depend on whether there is an intermediate block marker between it and the next signal. No block marker, no need for a blue aspect (AIUI).

Mar 16, 2012 21:49:23 GMT londonstuff said:

<snip>
In general the trains do seem to be slower in the central area of the line but quicker in the stretches, e.g. Finsbury to H&Islington.

I'm also absolutely surprised that, according to Diamond Geezer today, the new timetable isn't going to be implemented until March 2012. I know these things take time, but surely...

The work has been ongoing with the Vic now since, what, 2008? 2009? with the early closures, etc. and from a casual viewpoint, apart from the new trains there doesn't seem to have been any measurable improvement, not least in journey time. I'm certainly not trying to be negative and would love those in the know - Dan and Racka? - to tell me that I'm wrong.

Apparently the new timetable in March 2013 will make use of the speedier timings, but the current one still sticks to the 67 timings, e.g 3/4 mins between Finsbury and Seven Sisters or Highbury, where in reality 90seconds/2mins is far more realistic.

[Dave A]

Strangely enough, I was just looking at my Oyster history, and it showed that; using the line, more or less daily, from Victoria - Highbury & Islington (and vice versa) for the last few months, the average journey time is 16 mins versus 13 in the other direction. I presume this speed restriction isn't in place in the other direction then?

Also, I notice that I tend to be held in platforms for longer going Northbound (but that may be because I'm usually going home from work). ;D