WTT 36 April 2014

The Vic has been great for a couple of years now: very frequent trains, a minute or so between them, much cooler and much less crowded. 36tph is a different ball game through, especially when things go wrong.

wasnt there a feasibility study being done a few months ago to see if it was possible - I think I started a thread on it. Other than timetable changes and more staff and trains have there had to be any other mods to make this possible?

It may not sound like much of an increase in terms of seconds, but it is still a 10% reduction! which is the same reduction from 30 tph to 33 tph. With 36 tph, everything has to be that much tighter, and the slightest delay will have that much bigger an impact on the service. So I stand by my comment that 36 tph is a different ball game.

Actually it is it slightly less than a 9% reduction. The percentage change from 30 - 33tph is more than that from 33 - 36tph.

Will the 36 tph go hand in hand with a reduction in the end-to-end journey time, if the running time is less then the turnarounds won't be so tight. I stand by my comment that 33 tph was the big change, as not all trains could be accommodated in platforms. Introduction of stepping back at Walthamstow may actually make the operations easier than with 33 tph.

The Paris Metro line 1 manages a train every 105s without reliability seeming to suffer (although they do have platform edge doors and reversals beyond platforms at both ends).

I'm sure I read somewhere that the next step change would be to migrate from the current 1hr period of 33 tph each peak to operating 33tph for approximately 3hrs each peak. A step change from 33 to 36 tph in just 15 months is very impressive and speaks highly of the capabilities and reliability of both the new signalling system and the 2009 Tube Stock I suggest.

The info I got came directly from the timetables department at Broadway last week. There maybe a change in thinking since the new drivers that were meant to be starting their training on the line this week, have now been told they are going else-where and the line aren't getting any new drivers for a while, this in turn will effect the number moving from Brixton to Seven Sisters.

Why do the drivers need to move from Brixton to Seven Sisters?The depot's only been open a couple of years.

Train every 1 Minute 40 seconds compared to ever 1 minute 54 seconds what if their a failure!!?

andypurk - the thing is that the relationship between tph and reliability/deliverability is not a straight line but some sort of function, probably with steps rather than a smooth curve, so each 10% or whatever gets that much harder - more and more things need to work precisely (door speeds, point mechanisms, and so on) and more and more trains need to be delivered to time at junctions/crossovers/loops. A friend who was brought up on the Charlie Cope school of train operation recalled an attempt to run 42 tph on the Northern (presumably south of Kennington?) as an experiment to see what could actually be achieved as a theoretical maximum, but delivery to that level required stepping back and very tight platform control, which couldn't be justified financially.

@andy purk - Maybe "reliable" isn't quite the right word. I don't think there could ever be a clearcut yes/no answer to your question. Whilst there will be cases where a "10% more reliable set of assets" can enable you to run 10% more trains robustly throughout the service day, the problem is often that either the equipment or the staff cannot move 10% faster, as it were, and so that the next increment in service levels is unachievable except possibly on rare occasions, regardless of reliability improvements. It's at that point that the operation becomes "a whole new ball game", although precisely where that threshold will be crossed will depend entirely on the type of kit and operating practices involved, as you point out in your Northern/Victoria comparison.

I heard that the new timetable may not be introduced until the summer due so no need to worry about a change of rosters yet

42 trains per hour?!
What do you mean tight platform control? Surely running such a high frequency would boost passenger usage and hence fare income and help offset the costs? I would have thought the extra cost of new trains would be the real deterrent to running such an intensive service! Not to forget the extra heat caused by trains running every 102 seconds!



What depot is there at Brixton? I thought there's only 2 sidings I south of Brixton! What political motive ?

Thanks! However how would relocation be politically motivated?? It's not as if it would mean more jobs for South London residents!

I see, it's shame an unbiased Victoria line driver doesn't post and shed some light on the situation!

Three trains stable at Brixton overnight rather than two at present and stepping back at Walthamstow during the peaks.