Are trains deliberately never timetabled for precisely midnight?

[Gaelan]

Having a look at timetable data, it seems like there are no trains timetabled (in either the working or public timetables) to arrive, depart, or pass a station at exactly 0000. I'm curious if anyone knows the background here - I assume this is deliberately done to avoid confusion or some technical limitations? Does this constraint cause any scheduling irregularities, e.g. otherwise-hourly trains leaving a minute early/late to avoid a midnight stop?

One guess is that CIF-format schedules seem to use 0000 for "no public time" (for example, stations that are skipped or pick-up/set-down only), and they want to avoid that ambiguity.

For what it's worth, there are a few (6 in the timetable I was looking at) trains scheduled to pass a timing point at 0000½, but never to arrive or depart.

 

[Peregrine 4903]

There is a technical limitation where TRUST and TOPS can't handle 0000. So no trains are timed to depart at midnight on the network.

 

[station_road]

London Underground used to have timetabled departures at midnight, which was shown as 2400 but I don't know if that still happens

 

[JonathanH]

London Underground used to have timetabled departures at midnight, which was shown as 2400 but I don't know if that still happens

I think they run through to 2829. The TfL website however describes last train times at midnight as 00:00, including the last Jubilee train I caught at Green Park last night.

 

[pdeaves]

Yes, it is deliberate (as Peregrine 4903 says). There are slight blips in the scheduling (a pattern being a minute 'out'), but being the middle of the night, the effect is negligible.

 

[jfollows]

London Underground used to have timetabled departures at midnight, which was shown as 2400 but I don't know if that still happens

For example, a page from the Metropolitan Line working timetable 344, see 24:00 at Finchley Road (downloaded from https://tfl.gov.uk/corporate/publications-and-reports/working-timetables):

 

[Bletchleyite]

Correct, trains are not timed for 0000 due to the potential for confusion as to which day midnight belongs to. If a clockface pattern would mean an 0000 train, it's timed as either 2359 or 0001 instead. There used to be a short introductory passage in the old printed national timetable discussing stuff like this.

 

[Peregrine 4903]

Correct, trains are not timed for 0000 due to the potential for confusion as to which day midnight belongs to. If a clockface pattern would mean an 0000 train, it's timed as either 2359 or 0001 instead. There used to be a short introductory passage in the old printed national timetable discussing stuff like this.

That's not the reason. The reason is as I said due to the fact that TRUST and TOPS cannot handle 0000.

 

[Bletchleyite]

That's not the reason. The reason is as I said due to the fact that TRUST and TOPS cannot handle 0000.

That's the reason that was given by the old NRT, a passage which probably predates TRUST and TOPS! Though it's indeed possible these systems are deliberately configured not to accept 0000 for that reason, as there's no reason an IT system couldn't otherwise handle midnight.

 

[Peregrine 4903]

That's the reason that was given by the old NRT, a passage which probably predates TRUST and TOPS!

I wouldn't be so sure about that, TRUST and TOPS are both very old.

Plus if TRUST were to ever be replaced you would have trains departing/arriving at midnight.

 

[Bletchleyite]

I wouldn't be so sure about that, TRUST and TOPS are both very old.

Plus if TRUST were to ever be replaced you would have trains departing/arriving at midnight.

Well, as I said it is what the old NRT says pretty much word for word. I don't think you would choose to have midnight trains for that precise reason, unless the planners have forgotten that passage!

I can't find it to quote online, but perhaps if someone here possesses one they could post a copy of the exact wording.

 

[Peregrine 4903]

Well, as I said it is what the old NRT says pretty much word for word. I don't think you would choose to have midnight trains for that precise reason, unless the planners have forgotten that passage!

I can't find it to quote online, but perhaps if someone here possesses one they could post a copy of the exact wording.

Either way, if that was the reason in the past its not the reason now.

 

[Bletchleyite]

Found it on an older thread discussing this:

"Do not worry about the ambiguity as to which day Midnight itself belongs, for, to avoid this problem, all times skip from
2359 to 0001 and neither 0000 nor 2400 is ever used!"

Do trains have a timetabled departure of 00:00?

Ive never actually seen a timetabled departure or arrival of 00:00, only do I ever see is 23:59 or 00:01. Is there a 00:00 that exists anywhere in the current timetable, or has one ever existed?

www.railforums.co.uk

That is such an archaic wording, using "for" in that way, that I wouldn't be at all surprised if it predated TOPS/TRUST and was just rolled forward each year as standard copy.

 

[jfollows]

Either way, if that was the reason in the past its not the reason now.

I couldn't find it in the 1974 timetable, but it's in the 1993 timetable (I will post a text version shortly):

EDIT Sorry, no, that's not the relevant text .... will go look again. No, I can't find it, sorry. It's not in any of the GBPTTs I have - 1974, 1977, 1985 & 1992.

 

[Bletchleyite]

Either way, if that was the reason in the past its not the reason now.

It's quite possibly both.

 

[Peregrine 4903]

It's quite possibly both.

Its not the case anymore, I can pretty much guarantee that.

 

[Watershed]

Trains which would otherwise reach a timing point at midnight have an allowance added (usually adjustment allowance, which isn't shown in the public data - unlike pathing, performance and engineering allowances), or their dwell extended at the previous calling point. If an adjustment allowance is added in before midnight, this is a somewhat rare circumstance where it's permitted to use a negative adjustment allowance (to compensate for that). If there's a call that would otherwise fall at/over midnight, it's common for it to be adjusted so that it shows as being earlier, i.e. 23:59.

Of course, when overmidmight trains get retimed, you have to check that this doesn't cause any midnight timings! It's a surprisingly annoying task for operators with a lot of overmidnight trains (which inherently get amended a lot due to engineering works).

 

[JRT]

As an aside (not railways)
I remember local buses in Bradford used 2400 as midnight, particularly for the "midnight specials " on Friday and Saturday nights, well that was a long time ago.
National Express used BOTH 2359 and 0001 for midnight for fare purposes to avoid ambiguity (particularly day returns) as their "day" runs midnight to midnight.

 

[Wilts Wanderer]

Technically the working timetable and TRUST goes from 2359h to 0001. It is 0000 and 0000h that are never used. However planners must also be wary of anything arriving at a passenger call at 2359h as this would round up to 0000 in ‘public times’ - so it is normal to adjust the GBTT arrival time back to 2359, or to add {1h} mins to the WTT schedule so the arrival is 0001. There are several ways of doing it.

 

[Gaelan]

Plus if TRUST were to ever be replaced you would have trains departing/arriving at midnight.

I wouldn’t count on it—beyond TRUST itself, there are dozens of not hundreds of systems that consume timetable data, all of which could have been built around the assumption that nothing happens at midnight. You *could* go to the trouble of announcing the change and giving everyone sufficient time to make sure it wouldn’t break their system, but that’s a ton of effort and potential for issues for not much gain.

== Doublepost prevention - post automatically merged: 17 Apr 2023 ==

Technically the working timetable and TRUST goes from 2359h to 0001. It is 0000 and 0000h that are never used. However planners must also be wary of anything arriving at a passenger call at 2359h as this would round up to 0000 in ‘public times’ - so it is normal to adjust the GBTT arrival time back to 2359, or to add {1h} mins to the WTT schedule so the arrival is 0001. There are several ways of doing it.

I did find some trains timed to pass timing points at 0000h - not at my laptop at the moment, but I’ll look up which ones later tonight.

 

[Bletchleyite]

That could well be interpolated times by Realtime Trains?

 

[Peregrine 4903]

I wouldn’t count on it—beyond TRUST itself, there are dozens of not hundreds of systems that consume timetable data, all of which could have been built around the assumption that nothing happens at midnight. You *could* go to the trouble of announcing the change and giving everyone sufficient time to make sure it wouldn’t break their system, but that’s a ton of effort and potential for issues for not much gain.

== Doublepost prevention - post automatically merged: 17 Apr 2023 ==


I did find some trains timed to pass timing points at 0000h - not at my laptop at the moment, but I’ll look up which ones later tonight.

I get that but TRUST/TOPS is the one that prevents it from happening. And its quite time consuming process for TOC/NR Planners so is one from an efficiency viewpoint considered a gain.

 

[Gaelan]

That could well be interpolated times by Realtime Trains?

I’m not looking at RTT, I’m looking at the JSON data from Network Rail.

 

[Man_with_beard]

Today's modern computer tech can't register 00:00 for a departure screen yet my windows PC, phone, Tablet can all display 00:00... Something is seriously wrong here, maybe they're using the wrong programming. Don't the computers that operate departure boards run off windows? I'm sure I once saw the windows xp logo on a sleeping monitor at Birmingham new street some 20 years ago??

 

[Watershed]

Today's modern computer tech can't register 00:00 for a departure screen yet my windows PC, phone, Tablet can all display 00:00... Something is seriously wrong here, maybe they're using the wrong programming. Don't the computers that operate departure boards run off windows? I'm sure I once saw the windows xp logo on a sleeping monitor at Birmingham new street some 20 years ago??

There's a difference between a clock showing 00:00 (which is really just an interpreted version of a Unix timestamp in all likelihood) and a highly compressed data structure where 0's are used to denote 'blank' or 'no call'.

 

[30907]

I am fairly certain that the change, whatever the rationale, coincided with the standardisation of the 24-hour clock in 1965. Prior to that the column heading would have said "night" for eg the 12.0 Victoria to Brighton.

 

[Horizon22]

I've been told previously that 0000 is avoided because it cannot be handled by key systems, one of which is TRUST. The core system details are of course over 40 years old yet is embedded in a lot of the running of the railway.

No major issue instead planning for 2359 or 0001.

== Doublepost prevention - post automatically merged: 17 Apr 2023 ==

As an aside (not railways)
I remember local buses in Bradford used 2400 as midnight, particularly for the "midnight specials " on Friday and Saturday nights, well that was a long time ago.
National Express used BOTH 2359 and 0001 for midnight for fare purposes to avoid ambiguity (particularly day returns) as their "day" runs midnight to midnight.

On the Central line diagrams for the Woodford branch it uses the term "until 2400" which I presume is to stop passengers confused about what 0000 actually means as opposed to 2400 which is presumably easier to understand for the majority of people!

 

[zwk500]

I did find some trains timed to pass timing points at 0000h - not at my laptop at the moment, but I’ll look up which ones later tonight.

the 'h' from an NR time means 00:00:30, which is acceptable for passing times (as they don't have publicly advertised times).

 

[snowball]

My father, who was in the army in WWII, told me about 60 years ago that the military always avoid timing operations for 0000 or 2400 to avoid confusion over what day they refer to. I'm sure this was not because of the limitations of any computer system.

 

[TT-ONR-NRN]

My father, who was in the army in WWII, told me about 60 years ago that the military always avoid timing operations for 0000 or 2400 to avoid confusion over what day they refer to. I'm sure this was not because of the limitations of any computer system.

But as 2400 is not a real time, surely 0000 is the same day as 0001?