Unusual multiple unit couplings

[sad1e]

Class 315 and 365 in multiple working?

The provided image, dated 17th March 1997, depicts 365534 and 315803 passing Stratford, presumably heading to Ilford depot for maintenance. They appear to be coupled and under their own power. Bar the shape of coupler being the same, how was this possible whilst the trains were so different?

www.railforums.co.uk

Found this thread earlier that had a decent talk about 315's and 365's coupling and was wondering what other strange combinations would be possible in theory and which ones have been done in practice.

Presumably all of the Desiro city stock ( 700,707,717 ) can couple together as they're all of the same family although I've never heard or seen anything of this.

 

[stadler]

You can get some unusual Electrostar formations on empty stock workings. None of the different classes on Electrostar can couple in passenger service but they can certainly do so every now and again for empty stock workings. It happens multiple times a year.

375+377 happen occasionally for ECS workings only.

375+376 happen occasionally for ECS workings only.

376+377 happen occasionally for ECS workings only.

377+387 happen occasionally for ECS workings only.

I have not heard of it yet but i presume 379+387 workings may occasionally happen on ECS services now that Great Northern have both.

I know that a 319+455 formation and a 319+456 formation have both happened over fifteen or twenty years ago to rescue broken down units.

I presume that 700 and 707 and 717 stock can couple but i doubt it has ever happened. Maybe to rescue a broken down train. Would certainly be interesting if it has.

 

[norbitonflyer]

I presume that 700 and 707 and 717 stock can couple but i doubt it has ever happened. Maybe to rescue a broken down train. Would certainly be interesting if it has.

Neither 700 nor 717 are designed to couiple even to other members even of their respective classes in service, as the resulting train would be too long for any stations they serve. Emergency coupling only

 

[stadler]

Neither 700 nor 717 are designed to couiple even to other members even of their respective classes in service, as the resulting train would be too long for any stations they serve. Emergency coupling only

Yes obviously not in passenger service but it could certainly happen to rescue broken down trains. There was a couple of nights where two 700s worked as a 24 coach formation between Bedford and London when they were under test. I think this was done particularly to test the multiple working feature.

 

[frankmoh]

The Pacers, Sprinters and 170 can couple up with each other apparently.

I've seen Pacer and Sprinter together but not all 3 on one (presumably 6 car) train.

 

[reddragon]

The old SR stock all could inter work. A Class 33 or 73, with a class 201-7 or/and an EMU class 410-423 etc.

It happened with failures and was common during heavy snow, when a diesel could support an EMU in running it's service

Class 206 Tadpole was a class 201 with a class 416 driving trailer added

 

[Peter Mugridge]

...and here is one such instance; 2305 rescuing a failed 442 420 at Surbiton on 21st October 1989:

 

[reddragon]

Memories of extreme cold spell in 1987

A seasonal thread here. Does anyone have any memories of unusual traction or service patterns during the extreme cold and snowy spell around this time of year in January 1987? I do remember significant disruption and cancellation at the height of the spell on the Portsmouth Direct. While some...

www.railforums.co.uk

1987 is a good example

 

[eastwestdivide]

The old SR stock all could inter work. A Class 33 or 73, with a class 201-7 or/and an EMU class 410-423 etc.

It happened with failures and was common during heavy snow, when a diesel could support an EMU in running it's service

Class 206 Tadpole was a class 201 with a class 416 driving trailer added

I don't think the DEMUs could interwork with EMUs. The Tadpole DTs had to be rewired.
Also, the 4-SUB units couldn't interwork with the others, nor the 508s with the others. As the latter were introduced before the former were withdrawn, there was never quite a time when all the SR's EMU stock could couple and interwork in that way.
There were also other restrictions on coupling the EMU classes to do with current draw and gear ratios.

 

[nctd2306]

You can get some unusual Electrostar formations on empty stock workings. None of the different classes on Electrostar can couple in passenger service but they can certainly do so every now and again for empty stock workings. It happens multiple times a year.

Can older 377s (/1-/5) work in multiple in passenger service with the newer 377/6 and /7s?

 

[frankmoh]

I don't think the DEMUs could interwork with EMUs. The Tadpole DTs had to be rewired.
Also, the 4-SUB units couldn't interwork with the others, nor the 508s with the others. As the latter were introduced before the former were withdrawn, there was never quite a time when all the SR's EMU stock could couple and interwork in that way.
There were also other restrictions on coupling the EMU classes to do with current draw and gear ratios.

Well the 508s were not really meant for the Southern Region in the first place.

You also have perfectly normally coupling trains with some strange design decisions. The 414 was design to work with the 411 but had no cab-end gangways. Same story with the 456 and 455.

 

[norbitonflyer]

........., there was never quite a time when all the SR's EMU stock could couple and interwork in that way.

There was - before the first EPB appeared.

== Doublepost prevention - post automatically merged: 17 Oct 2025 ==

Well the 508s were not really meant for the Southern Region in the first place.

I thought they were. It was the change to Mk 3 emus that caused the two small PEP derived fleets to be consolidated into one fleet, rather than havibg two mixed fleets.

 

[nilvaj395]

...and here is one such instance; 2305 rescuing a failed 442 420 at Surbiton on 21st October 1989:

If we are counting these, there was that one time a 221 dragged a broken down 390!

 

[norbitonflyer]

You also have perfectly normally coupling trains with some strange design decisions. The 414 was design to work with the 411 but had no cab-end gangways. Same story with the 456 and 455.

The 41x classes (and the 40x classes before them) only had gangways if they had, or were intended to work with units that had, buffet cars. So the 4CORs and 4CEPs had them, but the 2HALs and 2HAPs did not. (The earlier 6PULs and 6PANs had a catering vehicle in each unit, so had no need of a gangway)

With the 45x's it was a whim of the design panel to get rid of gangways, resulting in the odd situation you describe. Even more strange was that the first such nongangwayed units, the 319s, needed their own bespoke front end as an emergency door was required because of the single track tunnels near Barbican

 

[eastwestdivide]

There was - before the first EPB appeared

Was there? I thought the pre-EPB stock also came in different and incompatible groups (A, B and C). D and E were the post-1951 groups which could interwork with some restrictions. Will try and find a source. Edit: see below.

Well the 508s were not really meant for the Southern Region in the first place

Regardless, they were on the SR at that time.

== Doublepost prevention - post automatically merged: 17 Oct 2025 ==

From Blood and Custard at

https://www.bloodandcustard.com/SR-4SUB.html

All the 4 SUB units could run in multiple with the 2 BIL /2 HAL /2 NOL /2 SL /2 WIM /3-Car Motor Units & 4 LAV units (up to twelve cars) but not with the 4 COR (etc) /5 BEL /6 CITY /6 PAN /6 PUL compatible range of units.

 

[norbitonflyer]

Was there? I thought the pre-EPB stock also came in different and incompatible groups (A, B and C). D and E were the post-1951 groups which could interwork with some restrictions. Will try and find a source. Edit: see below.


From Blood and Custard at

https://www.bloodandcustard.com/SR-4SUB.html

I didn't know that. So full compatibility ended in 1933 with the introduction of the PUL/PAN/BEL/CIT units.

 

[D3WY]

You can get some unusual Electrostar formations on empty stock workings. None of the different classes on Electrostar can couple in passenger service but they can certainly do so every now and again for empty stock workings. It happens multiple times a year.

375+377 happen occasionally for ECS workings only.

375+376 happen occasionally for ECS workings only.

376+377 happen occasionally for ECS workings only.

377+387 happen occasionally for ECS workings only.

I have not heard of it yet but i presume 379+387 workings may occasionally happen on ECS services now that Great Northern have both.

I know that a 319+455 formation and a 319+456 formation have both happened over fifteen or twenty years ago to rescue broken down units.

I presume that 700 and 707 and 717 stock can couple but i doubt it has ever happened. Maybe to rescue a broken down train. Would certainly be interesting if it has.

Im fairly sure 387 and 377s will qork together IF the 387 is boxed in with two 377s

Ie 377-387-377

So i overheard, someone may correct me on that. (Not that this is ever done anyway)

== Doublepost prevention - post automatically merged: 17 Oct 2025 ==

Can older 377s (/1-/5) work in multiple in passenger service with the newer 377/6 and /7s?

Yes, 6 series and 7 series are a "hybrid" so they have some 387 parts but the electronics are of a 377 so work fine together, I have driven a train with a 6 series one end and a 1 series the other, its just very weird when you change ends going from the newer 6 series and than bieng in a older more worn 1 series cab.

And it was odd having a 9 car train

 

[enginedin]

I see Scotrail running combinations that look a bit weird, like a 170 and a 158: https://www.realtimetrains.co.uk/service/gb-nr:Y66201/2025-10-17/detailed#allox_id=0 - but maybe these are less unusual than some of the other examples in this thread?

 

[MrJeeves]

377+387 happen occasionally for ECS workings only.

These are now common around Brighton, to take services into Lovers Walk.

Just the first 5 examples I found from trawling through the new open data feed we have for train consists:

https://www.realtimetrains.co.uk/service/gb-nr:Y33854/2025-10-18/detailed
https://www.realtimetrains.co.uk/service/gb-nr:Y11404/2025-10-18/detailed
https://www.realtimetrains.co.uk/service/gb-nr:Y35473/2025-10-17/detailed
https://www.realtimetrains.co.uk/service/gb-nr:Y35473/2025-10-16/detailed
https://www.realtimetrains.co.uk/service/gb-nr:Y33849/2025-10-15/detailed

 

[nilvaj395]

I see Scotrail running combinations that look a bit weird, like a 170 and a 158: https://www.realtimetrains.co.uk/service/gb-nr:Y66201/2025-10-17/detailed#allox_id=0 - but maybe these are less unusual than some of the other examples in this thread?

Apparently 153s and 170s have been coupled together on ScotRail for ECS moves but I also found a 156 and 170 together on an ECS move, which is rather strange.

https://www.realtimetrains.co.uk/service/gb-nr:Y72770/2025-10-12/detailed#allox_id=0

 

[TwinTurbostar]

Apparently 153s and 170s have been coupled together on ScotRail for ECS moves but I also found a 156 and 170 together on an ECS move, which is rather strange.

https://www.realtimetrains.co.uk/service/gb-nr:Y72770/2025-10-12/detailed#allox_id=0

153s and 170s ran in service together with London Midland and WMR.

 

[nilvaj395]

153s and 170s ran in service together with London Midland and WMR.

Interesting, I had always known about them working together in LM days, but not that it had carried on into WMR. Sidenote, on the forums, there is a picture of a 170 with both a 153 and a 150, as well as a 156 and 170 being coupled back in the First Scotrail era. It's seemingly very rare now though to see a 153/156 with a 170 on ScotRail, and only on ECS moves.

Was there any actual documented case of a 170 coupled to a pacer, or has this forever remained something that has never occurred, even though it's "technically possible"?

 

[stadler]

Interesting, I had always known about them working together in LM days, but not that it had carried on into WMR. Sidenote, on the forums, there is a picture of a 170 with both a 153 and a 150, as well as a 156 and 170 being coupled back in the First Scotrail era. It's seemingly very rare now though to see a 153/156 with a 170 on ScotRail, and only on ECS moves.

Was there any actual documented case of a 170 coupled to a pacer, or has this forever remained something that has never occurred, even though it's "technically possible"?

The issue is that the Scotrail 156 (and the Scotrail 153 too) and the Scotrail 170 have two different incompatible PIS systems. So they can easily couple and work together in passenger service but there will be no automated announcements or working screens. Because of that they try to avoid it. It used to be much more common to see a Scotrail 156 and Scotrail 170 coupled before they changed the PIS system. But the Scotrail 158 and Scotrail 170 still use the same PIS which makes coupling in passenger service work fine.

Central Trains used to couple their 170 units to all kinds of Sprinter stock. I have seen 150+170 and 153+170 and 156+170 and 158+170 workings in Central Trains days. They also very regularly coupled all different classes of Sprinter stock together.

I have heard a rumour that Northern occasionally had some 142+170 and 144+170 formations on ECS workings. I have also heard a rumour that Transport For Wales occasionally had some 142+170 and 143+170 formations on ECS workings. But i have yet to see any photographs or videos or any other evidence of it.

 

[Highlander1]

The issue is that the Scotrail 156 (and the Scotrail 153 too) and the Scotrail 170 have two different incompatible PIS systems. So they can easily couple and work together in passenger service but there will be no automated announcements or working screens. Because of that they try to avoid it. It used to be much more common to see a Scotrail 156 and Scotrail 170 coupled before they changed the PIS system. But the Scotrail 158 and Scotrail 170 still use the same PIS which makes coupling in passenger service work fine.

Central Trains used to couple their 170 units to all kinds of Sprinter stock. I have seen 150+170 and 153+170 and 156+170 and 158+170 workings in Central Trains days. They also very regularly coupled all different classes of Sprinter stock together.

I have heard a rumour that Northern occasionally had some 142+170 and 144+170 formations on ECS workings. I have also heard a rumour that Transport For Wales occasionally had some 142+170 and 143+170 formations on ECS workings. But i have yet to see any photographs or videos or any other evidence of it.

Scotrail have 170/158 pairings diagramed. They can often be seen working together through Fife and on Inverness to Edinburgh services. There are no diagrammed 170/156 services. Only Glasgow Queen Street conductors and drivers would sign both 156 and 170s anyway so they could only be used in passenger services to Anniesland, which would be slight overkill for capacity.

 

[Strathclyder]

When both were in service with ScotRail (so going back at least 15 years), 314+322 pairings occurred, but only on ECS moves between Shields Depot & Glasgow Central.

scot-rail.co.uk » Photo » 314 + 322 coupled in Glasgow Central

314+318 combos weren't unheard of either, but this usually only happened in the event of failures or ECS movements.

 

[matchmaker]

Scotrail have 170/158 pairings diagramed. They can often be seen working together through Fife and on Inverness to Edinburgh services. There are no diagrammed 170/156 services. Only Glasgow Queen Street conductors and drivers would sign both 156 and 170s anyway so they could only be used in passenger services to Anniesland, which would be slight overkill for capacity.

When ScotRail had 150s I have seen a 170/150 combo. The 170/158 combo is common.

 

[py_megapixel]

The Pacers, Sprinters and 170 can couple up with each other apparently.

I've seen Pacer and Sprinter together but not all 3 on one (presumably 6 car) train.

I have a vague idea (sorry, can't remember where from so might be completely wrong) that Pacer+170 formations were banned quite soon after the 170s arrived because they caused some sort of electrical problem (I think with the fire alarm in one of the units?)

 

[norbitonflyer]

When ScotRail had 150s I have seen a 170/150 combo. The 170/158 combo is common.

170/159 was used for a while on SWT

 

[TwinTurbostar]

Interesting, I had always known about them working together in LM days, but not that it had carried on into WMR.

Yep, even after the 170s had gained the 'temporary' WMR livery, with the 153s still in LM colours.

 

[DaveyJones]

The Class 221 and Class 390 are compatible for emergency working