Longest theoretical passenger train

[Pdf]

Given recent discussions about dual 10-car 701s or 805s and 807s working in multiple (both of these examples were test runs btw) I was wondering what the longest possible passenger train that could run in the domestically in the UK would be. Presumably two long units that can run in multiple travelling between stations with very long platforms. Ignoring the economics for now since this is Speculative Discussion.

I know a subleased 373 was used on the ECML for a while with a few doors locked out, so that was probably the longest in reality.

 

[NSE]

Are you differentiating between Multiple Units and Loco Hauled? Current the Caledonian Sleeper is the longest I believe.

An interesting question, because I seem to recall people saying that you were limited on the number of cabs in the formation and that was six. So, a 377 in 12 car formation is the longest it can be (just ignoring all things such as platform lengths for the purpose of this question). But I know 12 car 377 operate with 4x /3 units, which would be eight cabs. Not sure if there is anything in the current timetable, but I’ve seen it happen. I read that on here but it was ages ago. Is that the case? I appreciate it could quite easily change with different and newer types of stock.

Anyway, I’m rambling! Back to your question. I think empty, you may be able to run some lengthy formations but in service, I doubt anything would top the Caledonian Sleeper as platform lengths and signal sections and all that become an issue.

 

[waverley47]

Theoretically, you could run 2x9 car 80X in passenger service (bodging the TMS extensively) as the maximum in passenger service is two units.

This would completely screw the TMS as I said, but if it was possible, you would have a 520m long train, too long for any platform on any route served.

If you had a 5 car and a 9 car coupled, it would reach about 390m, short enough for platforms at Euston and Edinburgh, but pretty much nowhere else. I am aware the 26m long IETs don't serve Euston, but why let facts get in the way of a good speculative discussion.

Other than that, it's either a single IET at 260m or the sleeper.

 

[py_megapixel]

This would completely screw the TMS as I said, but if it was possible, you would have a 520m long train, too long for any platform on any route served.

Minor point of order: it would comfortably fit the longest platform at Gloucester, served by IETs on Paddington-Cheltenham.

I have no idea if the signalling there could cope with it - it's usually operated as two platforms that just happen to be connected end-to-end on the same bit of track - but since we've already established that the TMS couldn't, I don't see why that should be an objection!

 

[edwin_m]

Minor point of order: it would comfortably fit the longest platform at Gloucester, served by IETs on Paddington-Cheltenham.

I have no idea if the signalling there could cope with it - it's usually operated as two platforms that just happen to be connected end-to-end on the same bit of track - but since we've already established that the TMS couldn't, I don't see why that should be an objection!

18 cars of IET would be about 450m, comfortably within the limits for freight trains (though not on all routes). In principle the signalling should be able to cope.

But where would a train run to from Gloucester? Edinburgh also double length platforms capable of holding a (normal) full length train at each end. I can't immediately think of anywhere else but no doubt someone will be along with a suggestion.

 

[hexagon789]

18 cars of IET would be about 450m, comfortably within the limits for freight trains (though not on all routes). In principle the signalling should be able to cope.

But where would a train run to from Gloucester? Edinburgh also double length platforms capable of holding a (normal) full length train at each end. I can't immediately think of anywhere else but no doubt someone will be along with a suggestion.

Perth?

 

[stan claire]

 

[SynthD]

The train software is the first limit. Axle counters is another, and fixing a 255 limit is a larger job than it may sound. Would it be hard to find a route where you can be clear of every junction before being able to stop at the next signal?

 

[renegademaster]

Their is a video out there somewhere of 3 Southeastern electrostar units coupled together rescuing a dead unit. Cant seem to find it.
Found it.
23 car 375 with 6 different units, rescuing a train with broken shoegear

 

[stan claire]

Their is a video out there somewhere of 3 Southeastern electrostar units coupled together rescuing a dead unit. Cant seem to find it.
Found it.
23 car 375 with 6 different units, rescuing a train with broken shoegear

That was the one I originally tried looking for but couldn't find it at first, that's by far the most cursed one I've seen

 

[devon_belle]

Not close to a theoretical maximum, I don't think, but a friend that used to commute Exeter - Andover told me a few years ago that during some extreme disruption his 9 car 159 connected to a 6 car which was stuck in front of it. I can't confirm whether it's true or not, as he is not a train fan and could have miscounted. But if true, that would be 345m. I wonder how the TMS coped with that.

Since the limit for those sorts of trains is 10 cabs (?), I don't think you could run a passenger train with more than 5 159s. There are, of course, longer theoretical trains that can be formed as mentioned above.

 

[class ep-09]

Not close to a theoretical maximum, I don't think, but a friend that used to commute Exeter - Andover told me a few years ago that during some extreme disruption his 9 car 159 connected to a 6 car which was stuck in front of it. I can't confirm whether it's true or not, as he is not a train fan and could have miscounted. But if true, that would be 345m. I wonder how the TMS coped with that.

Since the limit for those sorts of trains is 10 cabs (?), I don't think you could run a passenger train with more than 5 159s. There are, of course, longer theoretical trains that can be formed as mentioned above.

TMS on 159?

 

[Howardh]

If you have a train with an engine connected to a train with an engine and connected to another train with an engine, etc etc, and (say) a circular track, the "combined" train could be, well, infinite? Each separate part has it's own power supply, the only thing is getting passengers on and off?! So it's the length of platform that would be key to it all...??

 

[Bartsimho]

If you have a train with an engine connected to a train with an engine and connected to another train with an engine, etc etc, and (say) a circular track, the "combined" train could be, well, infinite? Each separate part has it's own power supply, the only thing is getting passengers on and off?! So it's the length of platform that would be key to it all...??

As this doesn't say in the UK the longest platform is 1,507 metres long at Hubballi Junction, Karnataka, India.

So it could fit 11 5-car class 800's coupled together or 67 mk5 coaches (So almost the entire set of coaches the Caledonian Sleeper owns)

 

[Trainguy34]

I'd hate to dispatch there!

As this doesn't say in the UK the longest platform is 1,507 metres long at Hubballi Junction, Karnataka, India.

 

[Bartsimho]

I'd hate to dispatch there!

It's a station in India so I'd guess less procedures and clearance would have to be sought after to dispatch.

The platform length is about triple the length between West India Quays and Heron Quays on the DLR (ignoring that Canary Wharf station is in-between them).

 

[devon_belle]

TMS on 159?

Maybe not then - not my area of expertise.

 

[MarkyT]

In 2022, the metre gauge RhB (Rheatian Railway) in Switzerland ran 25 units of their new Stadler 'Capricorn' rolling stock coupled together over the Albula line in a consist 1,906-metre-long. They succeeded in setting a new world record for the longest narrow gauge passenger train movement. The train management system clearly couldn't cope with such a scale of multiple working so they had 7 drivers aboard working together in real time contact via a field telephone system provided by a local civil defence organisation. The train did carry a small number of guests but was clearly not in any kind of normal passenger service and the line was closed to other regular traffic for the duration so there were no concerns about reversing at termini etc. The train was initially formed up within the Albula tunnel.

https://www.rhb.ch/fileadmin/user_upload/redaktion/Ueber_die_RhB/Medien/Dokumente/Medienmitteilungen/Medienmitteilungen_2022/20221029_MM_Weltrekordversuch_english.pdf

 

[MattRat]

Theoretically, you could run 2x9 car 80X in passenger service (bodging the TMS extensively) as the maximum in passenger service is two units.

This would completely screw the TMS as I said, but if it was possible, you would have a 520m long train, too long for any platform on any route served.

If you had a 5 car and a 9 car coupled, it would reach about 390m, short enough for platforms at Euston and Edinburgh, but pretty much nowhere else. I am aware the 26m long IETs don't serve Euston, but why let facts get in the way of a good speculative discussion.

Other than that, it's either a single IET at 260m or the sleeper.

Wouldn't 2x7 cars be a similar length to a 5 and 9? Which Avanti could run if 807s were allowed past Weaver Junction, for a non stop Euston to Edinburgh run.

 

[waverley47]

Wouldn't 2x7 cars be a similar length to a 5 and 9? Which Avanti could run if 807s were allowed past Weaver Junction, for a non stop Euston to Edinburgh run.

The LNER and GWR lengths are 26m per coach, and from memory the new Avanti ones are 24m, giving a 2x7 length of 340m give or take, so possibly, but incredibly unlikely.

 

[ac6000cw]

18 cars of IET would be about 450m, comfortably within the limits for freight trains (though not on all routes). In principle the signalling should be able to cope.

But where would a train run to from Gloucester? Edinburgh also double length platforms capable of holding a (normal) full length train at each end. I can't immediately think of anywhere else but no doubt someone will be along with a suggestion.

Cambridge in theory (P1+P4 is 470m).

Would it be hard to find a route where you can be clear of every junction before being able to stop at the next signal?

Freights are routinely much longer than 450m, so it shouldn't be.

 

[Pdf]

The LNER and GWR lengths are 26m per coach, and from memory the new Avanti ones are 24m, giving a 2x7 length of 340m give or take, so possibly, but incredibly unlikely.

Only the 810s being built for EMR have 24m coaches.

 

[liamf656]

Recently EMR performed a 14 coach rescue move using two 7 car 222s

Thameslink also had a 5Z99 just the other day, a 16 coach 700 formation. There were talks to use a third unit after the original consist had further problems, creating 24 coaches, but I don't believe this came to fruition

 

[The Ham]

It would be interesting to see what would be possible in a post HS2 works, given that would be running (presumably) 16*25m coach stock.

A 32 coach train (one rescuing another) would be quite something to see.

 

[dciuk]

Not close to a theoretical maximum, I don't think, but a friend that used to commute Exeter - Andover told me a few years ago that during some extreme disruption his 9 car 159 connected to a 6 car which was stuck in front of it. I can't confirm whether it's true or not, as he is not a train fan and could have miscounted. But if true, that would be 345m. I wonder how the TMS coped with that.

Since the limit for those sorts of trains is 10 cabs (?), I don't think you could run a passenger train with more than 5 159s. There are, of course, longer theoretical trains that can be formed as mentioned above.

This youtube video says up to 6 class 158 units can be coupled together (around the 2 minute 30 second mark) Not sure if anything is different with the 159's that would only allow 5.

 

[ac6000cw]

Recently EMR performed a 14 coach rescue move using two 7 car 222s

Thameslink also had a 5Z99 just the other day, a 16 coach 700 formation. There were talks to use a third unit after the original consist had further problems, creating 24 coaches, but I don't believe this came to fruition

2 x 12-car 700s would give you a roughly 485m long train with only 4 cabs, and I wouldn't be surprised if that has happened occasionally as a rescue or ECS move (but no knowledge of it). That's a bit longer than 2 x 9-car IET.

 

[Vexed]

2 x 12-car 700s would give you a roughly 485m long train with only 4 cabs, and I wouldn't be surprised if that has happened occasionally as a rescue or ECS move (but no knowledge of it). That's bit longer than 2 x 9-car IET.

There is indeed a video of a 2 x 12 car 700, from 2015 when they were undergoing testing.

 

[Peterthegreat]

I believe in days of yore (probably 70/80s or before) the absolute maximum for a passenger train in normal service was 20 coaches.