TfW class 398 Stadler Citylink tram trains

[Daniel Boone]

It's not, but it makes sense to start with the Bay services especially early on when the fleet will encounter new service issues (as happened with the 756s early on) but you can't run them on that route until the Bay wires go live.

Fair enough, running them on ponty-bay diagrams does seem to be their goal at the moment and you're right about the logic.

 

[MikePJ]

Bay wires are supposed to go live on 23rd March.

 

[VR494]

New software has been introduced this week which appears to have helped with the coupling issues and units responding to each other.

Test drivers also reporting back that they have had a much more positive week, although not all the diagrams have run.

There’s still a long way to go, but driver training are hoping to pilot something towards the end of March, early April if all goes to plan. There’s still trade unions and other items to go as well.

Believe what you want, but don’t expect one anytime soon. The other issue mentioned have not gone away.

 

[tfw756rider]

New software has been introduced this week which appears to have helped with the coupling issues and units responding to each other.

Test drivers also reporting back that they have had a much more positive week, although not all the diagrams have run.

There’s still a long way to go, but driver training are hoping to pilot something towards the end of March, early April if all goes to plan. There’s still trade unions and other items to go as well.

Believe what you want, but don’t expect one anytime soon. The other issue mentioned have not gone away.

At least there has been some small progress though - any is moving in the right direction. Your contributions are much appreciated.

 

[56xx]

In the light of the issues with the 398s discussed elsewhere, I'm wondering if TfW will bring forward plans to move the 398s to the Coryton/Penarth/Caerphilly services, releasing the 3-car 756s for use elsewhere. This will need some electrification on the Penarth branch, which is owned by Network Rail. The cheapest option would be to install single-wire tramway-style catenary (at 25kV) between Cogan Junction and Penarth. As the maximum speed here is 35mph, there's no need for anything more substantial. Of course, Network Rail may object on the basis that it's nonstandard, but the line doesn't serve any freight and nor is it ever likely to.

This is what really needs to be done to keep the 398s where they really belong and release the 756s to where they really belong.
Hopefully Network Rail will concede if TfW request.

 

[Cardiff123]

This is what really needs to be done to keep the 398s where they really belong and release the 756s to where they really belong.
Hopefully Network Rail will concede if TfW request.

Even if NR agreed to it, the response from the UK Treasury whether to fund it, will be the usual, default "No".

 

[VR494]

Even if NR agreed to it, the response from the UK Treasury whether to fund it, will be the usual, default "No".

I believe this was the original barrier that resulted in the Welsh Government buying the valley lines from Network Rail.

The 398 project if done correctly, could make a real difference. Unfortunately, they have been let down by a number of key impact factors ranging from a depot that is restricting in its operational functionality and the lack of adequate electricity.

The 398’s have a range of around 6-9 miles on battery, taking into account the battery and its reserve, the reality is around just 6 miles of actual use. Honestly, if these things end up being delayed around Cardiff, the potential for a major delay and disruption is highly likely. Rescue units are going to have the same limited battery capacity, and you can see where this is going.

The OLE installed can only work with custom built rolling stock, limiting the ability be flexible in the future as well.

If only someone had taken a step backwards and actually looked at what they were ordering and been relatively realistic, it’s mind blowing.

Listening to the board’s ambition, they may even be looking to order more of these things as well to cover other CVL lines in the future. Enjoy your flirts while they last, they are destined for other things in years to come.

 

[John R]

The OLE installed can only work with custom built rolling stock, limiting the ability be flexible in the future as well.

Are you referring to the fact that it is discontinuous, which if so is a given, and we are likely to see a lot of bi-mode stock ordered in future (see also Fife and Borders).

Or is there something else about it that makes it only useable by a certain type of emu. The 756s seem to handle it ok (?)

 

[VR494]

Are you referring to the fact that it is discontinuous, which if so is a given, and we are likely to see a lot of bi-mode stock ordered in future (see also Fife and Borders).

Or is there something else about it that makes it only useable by a certain type of emu. The 756s seem to handle it ok (?)

Only the 756 and 398 units have the required beacon readers and software to operate under the discontiguous OLE.

The 756’s maybe destined for mainline deployment at a later date. It’s likely more 398’s will be ordered. Penarth and Coryton will likely be getting 398’s at some point in the future allowing 3 car 756 onto Cardiff-Bristol services.

 

[John R]

Only the 756 and 398 units have the required beacon readers and software to operate under the discontiguous OLE.

The 756’s maybe destined for mainline deployment at a later date. It’s likely more 398’s will be ordered. Penarth and Coryton will likely be getting 398’s at some point in the future allowing 3 car 756 onto Cardiff-Bristol services.

Ok, but you make it sound like a big thing that will be a showstopper, whereas that was known from the get go, and there is no intention to use any other ac stock on the network. And even if there was, I would imagine the retrofit of such a facility would be perfectly possible. (Of course, such units would have to be bimode too, which would severely limit options anyway).

Discontinuous electrification, and multi-powered units are likely to be the norm for future rolling stock provision outside the South East. As evidenced by the BEMU tender getting under way in Scotland.

 

[VR494]

Ok, but you make it sound like a big thing that will be a showstopper, whereas that was known from the get go, and there is no intention to use any other ac stock on the network. And even if there was, I would imagine the retrofit of such a facility would be perfectly possible. (Of course, such units would have to be bimode too, which would severely limit options anyway).

Discontinuous electrification, and multi-powered units are likely to be the norm for future rolling stock provision outside the South East. As evidenced by the BEMU tender getting under way in Scotland.

There’s a big difference between a BMEU and a tram-train. The 756’s are fantastic units and don’t get the credit they deserve to be honest. Even the WSP is fantastic on them.

The 398, is a tram and certainly not a train in terms of robustness. The braking system is also completely different, and time will tell if current train drivers will be able to adapt to the changes in driving style required on these.

Tfw also went for the high floor variant, and it has the provisions of AWS and TPWS to run on a heavy rail infrastructure. They didn’t counter into the equation the need for a third power source such as a diesel generator, which some European countries have on theirs. Neither did they realise that using them as a train intensively 95% of the time would cause issues.

In my opinion they have their place on the street, and should be kept away from the railway. But that’s my old school argument having been on the railway a long time. Yes, I’ve seen changes and advances in technology, but nothing as ridiculous as sending a tram up the valleys, full of old mine shafts and calling it a train.

 

[John R]

Yes, but one minute you’re confirming that the key difference is the technology required to pan up and down that makes them bespoke, and when I challenge that you say it’s because they are tram trains and list all their faults.

The OLE installed can work with tram trains or heavy rail stock - and indeed does, so listing the faults of the 398s isn’t relevant to the OLE used.

 

[chargesmith]

Rail magazine article about the 398s:

Transport for Wales explains benefits of tram-trains - all hoped to be in service this year

TfW in final stages of testing tram-train units before they enter service on Core Valley Lines in South Wales.

www.railmagazine.com

CEO is still saying they should be in service this year. Interestingly they are saying drivers will be involved in opening doors.

 

[VR494]

Yes, but one minute you’re confirming that the key difference is the technology required to pan up and down that makes them bespoke, and when I challenge that you say it’s because they are tram trains and list all their faults.

The OLE installed can work with tram trains or heavy rail stock - and indeed does, so listing the faults of the 398s isn’t relevant to the OLE used.

No current EMU except the 756 or 398’s can use the OLE on the TAM or CAR lines. A bespoke system is installed on the network which only these units are designed around. If tfw wants more trains, they will need to be bespoke to the network.

The way the trains and trams interact with the PES sections using beacons instead of APC magnets, the fact the trains use battery and are fast charged by the OLE instead of running on the juice, and the power draw limits on capacity means a fleet of pure EMU’s are not suitable unfortunately without a redesign.

The areas the pantograph raises and lower automatically mean drivers would have to do this on the move to.

The only realistic option to run these things will be to and from the Bay. The risk of getting gapped out over network rail infrastructure is very real, and due to the cost of delays and the issues around rescuing one was the reason why they were denied permission to test them between STJ and CDF.

There’s also the issue of an ADD in service, the unit is then on battery even under the wires and they only have 1 pantograph.

They need modifications, either upgrade the batteries which probably won’t be possible due to cooling or retrofit with a diesel generator.

The CEO needs to get his head around this and stop flogging a dead horse. There is no way they can train everyone by the end of 2026 to drive these.

The engineers are telling them it’s not going to work, however maintaining a fixed attitude that we will continue forward and ignore advice and hope for the solution is not the way to go about it.

 

[Chris125]

But that’s my old school argument having been on the railway a long time.

So ultimately this boils down to 'heavy rail good, light rail bad' because that's all you know? That's not an objective argument, it's just a form of 'not invented here' syndrome.

 

[Benjwri]

The risk of getting gapped out over network rail infrastructure is very real, and due to the cost of delays and the issues around rescuing one was the reason why they were denied permission to test them between STJ and CDF.

They didn’t test them between Cardiff and Severn Tunnel Junction because they were worried about them running out of battery on the continuously electrified mainline?

 

[VR494]

So ultimately this boils down to 'heavy rail good, light rail bad' because that's all you know? That's not an objective argument, it's just a form of 'not invented here' syndrome.

Why would heavy rail workers who currently have good working conditions want to be introduced to light rail, that is not so heavily regulated, but that’s another topic on its own and for Aslef to sort out in the not so distant future no doubt.

== Doublepost prevention - post automatically merged: 17 Feb 2026 ==

They didn’t test them between Cardiff and Severn Tunnel Junction because they were worried about them running out of battery on the continuously electrified mainline?

No, the problem was more to do with assisting one and they didn’t want to loose the capacity of the relief lines.

 

[John R]

Why would heavy rail workers who currently have good working conditions want to be introduced to light rail, that is not so heavily regulated, but that’s another topic on its own and for Aslef to sort out in the not so distant future no doubt.

Ah, so is the real underlying reason for your dislike of the units coming clear now.

In what way are the TAM lines less heavily regulated? It still falls under ORRs remit, and I don’t think it is planned to reduce the lines to light rail status?

 

[Dai Corner]

Why would heavy rail workers who currently have good working conditions want to be introduced to light rail, that is not so heavily regulated, but that’s another topic on its own and for Aslef to sort out in the not so distant future no doubt.

I thought it was agreed years ago that the TAM lines would continue to be operated on heavy rail principles with full signalling and safety-critical guards.

 

[The exile]

Tfw also went for the high floor variant, and it has the provisions of AWS and TPWS to run on a heavy rail infrastructure. They didn’t counter into the equation the need for a third power source such as a diesel generator, which some European countries have on theirs. Neither did they realise that using them as a train intensively 95% of the time would cause issues.

Karlsruhe says “hi”. OK, just dual voltage with no batteries (and no diesel), but almost always running as trains (and on longer runs with even greater climbs than on the Valleys routes). Now much of the inner-city sections are in tunnel, there’s even less tram-style running (though the tunnel sections are still tramways).

 

[Tom125]

This is now quite telling ... seems the issue is a public sector organisation going through a necessary re-organisation (heavy to light rail) vs the status quo. This bit is always the hardest bit: confusion, fear, worry (when the change really begins), ride though it and in 3 years you'll be looking back proudly at what been achieved in the valleys: you'll have a well run light rail network which transforms the communites it serves (after all that's what it's about: the passengers and residents of the Cardiff area and Cardiff valleys). I speak from experience leading a public sector organisation: people hate change and they fight it.

 

[6opher]

I thought it was agreed years ago that the TAM lines would continue to be operated on heavy rail principles with full signalling and safety-critical guards.

It is being run on heavy rail principles hence why the units are not trams. They are tram-trains with heavy rail bogies to allow them on the current heavy rail lines.
There will be a second person (guard) on the units when on heavy rail but not sure if they keep the safety critical part of their role. I would think so but who knows if that’s the case once (or if) the drivers do the doors.

== Doublepost prevention - post automatically merged: 17 Feb 2026 ==

This is now quite telling ... seems the issue is a public sector organisation going through a necessary re-organisation (heavy to light rail) vs the status quo. This bit is always the hardest bit: confusion, fear, worry (when the change really begins), ride though it and in 3 years you'll be looking back proudly at what been achieved in the valleys: you'll have a well run light rail network which transforms the communites it serves (after all that's what it's about: the passengers and residents of the Cardiff area and Cardiff valleys). I speak from experience leading a public sector organisation: people hate change and they fight it.

No it will not be a light rail network at all hence why these hybrid units are being used. I don’t see all the heavy rail track being ripped up and replaced. Does anyone?

 

[Tom125]

It is being run on heavy rail principles hence why the units are not trams. They are tram-trains with heavy rail bogies to allow them on the current heavy rail lines.
There will be a second person (guard) on the units when on heavy rail but not sure if they keep the safety critical part of their role. I would think so but who knows if that’s the case once (or if) the drivers do the doors.

== Doublepost prevention - post automatically merged: 17 Feb 2026 ==


No it will not be a light rail network at all hence why these hybrid units are being used. I don’t see all the heavy rail track being ripped up and replaced. Does anyone?

Doesn't change the sentiment: TfW need to rid the negative attitude around these tram trains with employees that is toxic to an organisation. Engineers with solve the technical issues: they are problem solvers and I rank them as some of the most creative and intelligent people I've ever met. TfW however should be reminding all staff who their first duty is to: the safety and movement of the travelling public.

 

[Dai Corner]

It is being run on heavy rail principles hence why the units are not trams. They are tram-trains with heavy rail bogies to allow them on the current heavy rail lines.
There will be a second person (guard) on the units when on heavy rail but not sure if they keep the safety critical part of their role. I would think so but who knows if that’s the case once (or if) the drivers do the doors.

== Doublepost prevention - post automatically merged: 17 Feb 2026 ==


No it will not be a light rail network at all hence why these hybrid units are being used. I don’t see all the heavy rail track being ripped up and replaced. Does anyone?

To clarify, I was talking about the operating rules rather than the number of pounds of steel in each foot of rail when I referred to 'heavy rail'.

 

[6opher]

Doesn't change the sentiment: TfW need to rid the negative attitude around these tram trains with employees that is toxic to an organisation. Engineers with solve the technical issues: they are problem solvers and I rank them as some of the most creative and intelligent people I've ever met. TfW however should be reminding all staff who their first duty is to: the safety and movement of the travelling public.

Don’t care about sentiment. I’m just talking reality (I think)
I actually don’t get the negative attitude towards them. Passengers will just be in a saloon getting from A to B on more frequent journeys. Complaining when they haven’t even stepped foot on one. At least wait until they are out. The mind boggles but each to their own.

 

[tfw756rider]

Don’t care about sentiment. I’m just talking reality (I think)
I actually don’t get the negative attitude towards them. Passengers will just be in a saloon getting from A to B on more frequent journeys. Complaining when they haven’t even stepped foot on one. At least wait until they are out. The mind boggles but each to their own.

I also wouldn’t be taking everything that VR person is saying as correct either as I’ve seen plenty of things that I know are wrong.

"That VR person" (@VR494), in their short time with us so far, has generously provided us with a lot of "behind the scenes" information that they didn't have to provide us with.

What are the plenty of things that you know are wrong?

 

[800001]

398032 observed this afternoon at Asfordby (Old Dalby test track).

 

[Cardiff123]

I believe this was the original barrier that resulted in the Welsh Government buying the valley lines from Network Rail.

Yes it was, because by 2014/15, with large swathes of the electrification that was promised in 2011/12 getting cancelled, Welsh Govt realised that the only way to get the Valley Lines electrified was to take responsibility for it themselves and secure EU structural funds to fund it.

Listening to the board’s ambition, they may even be looking to order more of these things as well to cover other CVL lines in the future. Enjoy your flirts while they last, they are destined for other things in years to come.

If that happens, Cardiff - Barry Island & Bridgend would be severed from the Valley Lines after how many decades? Through running to Queen Street is a key passenger flow from Barry.

 

[VR494]

There is no status quo, well unless you’re based at a certain depot down west. And from what I can see the staff are keen to move on and learn the new traction. I have an opinion on tram-trains, so do many senior colleagues, who are experienced enough to know they are not fit for this kind of work. We are not Germany or Manchester and the area is very unique. Would it benefit from a metro, definitely, however the valleys are completely deprived and there is nothing left in terms of work.

Moving on, an agreement called DRI3 has set up the future valley drivers and gaurds for massive changes to their working environment. This does not affect the mainline, who outvoted them on something that they should never have been allowed to be included in. The majority of senior drivers will be gone soon anyway, when the time comes, and that will be 398 rollout no doubt.

You for sure can expect more delays with these compared with the flirts. Customers have waited years on the valleys to have decent trains, now they have them they will soon be taken away and replaced, it’s a shame.

Valley drivers are also in for a shock when they see what is to come on these, and they are being told they are trains, tram drivers will be employed to do the latter bits etc by union guys, who are more concerned in getting out of working trains altogether.

The truth is they won’t, the current drivers are doing that bit too! And once signed up on line of sight for the bay, it will gradually get introduced elsewhere on the valleys. By then you are already trained and there is nothing you can do about it.

I’ve heard over and over as long as they pay me 70k I’d drive anything. Current drivers will be downgraded in the future, and tfw will save thousands in wages per unit on the network, lowering the cost per mile for passengers.

When the time is right they are going to order more soon for the rest of the CVL, and the flirts will be moving to the mainline. Yes Rhymney line enjoy your toilets!

Mainline will then get dissolved into GBR and you have the valleys, light rail system running as an entire system on its own. All signalling controlled from Taffs well. Tfw will then franchise it off as a completely different network to the highest bidder, stick a different colour T on the network, passing on the operating costs form the government.

The issues mentioned with the 398’s are valid, and the team are working away trying to meet a deadline. More cash is needed and sadly it’s not coming in the quantities they would like.

I’d happily welcome a second opinion to correct the incorrect assumptions made here. All opinions were based on operational experience with the units and seeing designs and procedures first hand.

Luckily I’ve not got long left in this industry, and like many other colleagues we wish them all the best. But don’t say we didnt tell you about it!

 

[tfw756rider]

There is no status quo, well unless you’re based at a certain depot down west. And from what I can see the staff are keen to move on and learn the new traction. I have an opinion on tram-trains, so do many senior colleagues, who are experienced enough to know they are not fit for this kind of work. We are not Germany or Manchester and the area is very unique. Would it benefit from a metro, definitely, however the valleys are completely deprived and there is nothing left in terms of work.

Moving on, an agreement called DRI3 has set up the future valley drivers and gaurds for massive changes to their working environment. This does not affect the mainline, who outvoted them on something that they should never have been allowed to be included in. The majority of senior drivers will be gone soon anyway, when the time comes, and that will be 398 rollout no doubt.

You for sure can expect more delays with these compared with the flirts. Customers have waited years on the valleys to have decent trains, now they have them they will soon be taken away and replaced, it’s a shame.

Valley drivers are also in for a shock when they see what is to come on these, and they are being told they are trains, tram drivers will be employed to do the latter bits etc by union guys, who are more concerned in getting out of working trains altogether.

The truth is they won’t, the current drivers are doing that bit too! And once signed up on line of sight for the bay, it will gradually get introduced elsewhere on the valleys. By then you are already trained and there is nothing you can do about it.

I’ve heard over and over as long as they pay me 70k I’d drive anything. Current drivers will be downgraded in the future, and tfw will save thousands in wages per unit on the network, lowering the cost per mile for passengers.

When the time is right they are going to order more soon for the rest of the CVL, and the flirts will be moving to the mainline. Yes Rhymney line enjoy your toilets!

Mainline will then get dissolved into GBR and you have the valleys, light rail system running as an entire system on its own. All signalling controlled from Taffs well. Tfw will then franchise it off as a completely different network to the highest bidder, stick a different colour T on the network, passing on the operating costs form the government.

The issues mentioned with the 398’s are valid, and the team are working away trying to meet a deadline. More cash is needed and sadly it’s not coming in the quantities they would like.

I’d happily welcome a second opinion to correct the incorrect assumptions made here. All opinions were based on operational experience with the units and seeing designs and procedures first hand.

Luckily I’ve not got long left in this industry, and like many other colleagues we wish them all the best. But don’t say we didnt tell you about it!

All of the information about the 398s that you have contributed to this site has been much appreciated (at least by some of us!), and all the best to you too.