victoria line frequency?

Trains every 60 seconds would mean running 60TPH jardine01...not possible.
30TPH would mean a train every 2 minutes which is acceptable.

Count the time a train takes to enter a platform, open the doors, passengers disembark, passengers board, doors close, brakes release and the train leaves the station. Let's say this is 60 seconds. Now you see it's impossible to have a train every 60 seconds...

Yes, at such frequencies they will be... and they'll need to be timetabled, and run, to within a few seconds

@nick023 it should possible to get 'stopped' time to about 45 sec - then there is no need for the first train to have cleared the platform before the next is running in (with signalling to permit this), so 60 tph should be doable - if not with current signalling.

A question I put to the Trains magazine forums as to max frequencies produced the following responses:

"In the early 1960s, CTA [Chicago] was running the State Street Subway (ABS with track trips) on an alternating 60-90 second headway (Englewoods were on the 60 second interval, with Jackson Parks running to the 90 second interval). Pre-cab signals, and also pre-State Street Subway (so before 1943) the Loop "L" was operated with trains double-berthing at stations in the peak. While it might have been slow-going, this meant the time between trains was probably on the order of at most 15-20 seconds from the time the first one took off till the follower got going." (artpeterson)

and

"More New York memory: After the 2nd Avenue elevated was abandoned and torn town, some of its traffic, including the rush hour Freeman Street expresses that shared tracks with the 7th Avenue and Lexington Avenue subway trains on the West Farms Bronx elevated structure, was shifted to the Third Avenue elevated. In the direction of rush hour, the express track and the local track each saw a train about every 120 seconds, departure from station to departure from station. The center reversable-direction express track was signalled to handle a 90-second headway, just like signalling on most subway lines. (Signalling does not mean that the close headway is acheived. In most cases, except those noted earlier, the headways were longer.) But all this equjpment had to turn around in downtown Manhattam which meant that the local track in opposite direction from the rush hour was seeing a train every minute, every 60 seconds. The local tracks were not signalled exept at switches. The reverse-direction trains thus ran on site, not very fast, sort of like the Chicago loop perfomance except for a much greater distance. All carried passengers and ran as locals making all local stops, including gate-car through expresses on the non-rush direction trip. " (daveklepper)

Have you? Is it? Why? Do you mean maximum non-internally delaying frequency? Too many trains, not enough time to board.



Is that because we have termini in London?

Trains per hour is not the be all and end all of providing a high performance railway. It would be possible to run 60 tph I am sure, but with a moving block system and low line speeds (so trains could run very close together, allowing trains to run very close behind each other.

I'm sure the Victoria Line post upgrade will support 33tph (109s between trains). I don't remember what the signalling headway is, but around 60s rings a bell (I'll check when I remember). Add in dwell times of 20-30secs gives 80-90s headway capability, but you wouldnt run to that because it would all go tits up with the slightest delay.

If they used to run higher frequencies on the Northern line why cant they not do it today? Obviously with the 1995 stock being limited in power it would be inpossible.

Not really, changes in signaling rules maybe, especially Moorgate control, but not really H&S rules.

However, one of the main reasons is that trains have got longer and so it takes more time for them to clear pointwork etc. They also have to approach platforms more slowly to make sure that they stop in the correct spot as there is often no 'spare' platform space.

With a layout like the loop at Kennington Charing Cross branch at each end of a line it should be possible to increase frequency over that seen on current lines with current signaling rules and ATO.

On the victoria line trains do sometimes come every 1 minute often once on train goes the other one comes in. But it is really annyoing in tunnels when we are often stuck there for 15 minutes sometimes because we are too close to the train ahead! However with 100% 2009 stock it was genrally the 1967 stock which were holding the 2009's up.

I'm sure the existing system offers signalling headways around 60s in the central area, so this is possible if the following train is running in just as the train in the platform starts to leave.



Go on, I'm intrigued how the 1967 stock can hold up the 09 stock when there are none on the line.