Class 701 'Aventra' trains for South Western Railway: progress updates

[TEW]

Any news on additional 701 diagrams for next week?

Another main suburban diagram is introduced. The effective additional diagram starts and ends at Guildford, although it swaps at Waterloo after the first train with a current diagram to cycle units around.

 

[WWTownEnth]

Another main suburban diagram is introduced. The effective additional diagram starts and ends at Guildford, although it swaps at Waterloo after the first train with a current diagram to cycle units around.

Thanks. Maybe we will get some main line strengthening as well next week the with the displaced 450s

 

[swr444]

I really hope they remove the 450s from the Reading route soon.

== Doublepost prevention - post automatically merged: 15 Apr 2026 ==

Looks like it's the diagram which has 2J05/2J12 + 2F87/2G22 on it which changes over next week

 

[Big Jumby 74]

Although you have to go back 12 years for when everything on the mainline suburban and Windsor lines was last 8 cars

Very true indeed. But without giving too much away here in relation to who was involved in the detailed planning of the SWT 10 car plan introduction (which didn't address all suburban services as is well known), much work was undertaken by many experienced railway people on the ground to maximise siding extensions and modifications, at every suburban location possible, including Wimbledon depot, Clapham Yard, Staines, Strawberry Hill, Guilford and Woking to maximise the number of sidings that could accommodate 10 car trains instead of 8 cars within the suburban area.

It was known at the time, that any further increase in 10 car formations post SWT days (as per the 701 plan) would not work within the stabling capacity that existed even after all that SWT work to accommodate all 10 car 458/5, 455/456 and 707 formations were up and running, and further stabling space would be required.

Feltham, I hear some shout ! A must have, and this was also looked in to many years ago in conjunction with BAA in relation to proposals for a new Airport service, along the Windsor side lines but this fell by the wayside for whatever reasons (lack of ££/realism etc possibly?), but even Feltham in todays incarnation (10 x 10 car roads) as welcome as it is, does not meet the needs of 10 car service provision in respect of the main suburban group of services, a large proportion of which have to be resourced from Wimbledon Depot Top Yard in order for the overall timetable plan to work.

It's a simple case of adequate pathways (for empty trains) when starting up the service each morning, combined with adequate stabling capacity for the formations concerned (10 car sidings), so as not to interfere unduly with neighbouring service groups, thus reducing risk to the overall plan if one such group suffers melt down on any occasion.

Feltham was a welcome addition to overall capacity needs, but in reality is in the wrong place - when taken against the pre 2017 timetable which was reasonably well balanced in respect of service provision each morning - ie: where empty trains came from to start up the service each day which had minimal impact on the passenger timetable.

I suspect there are still difficult decisions to be made in this matter, which will to some degree possibly impact on passenger capacity on some early (and late?) services, be that some shorter formations (ie 5 car 701) or possibly some services removed from the timetable to create pathways for additional empty moves to start the service up each day, particularly if pre covid service levels are to be re-implemented in a greater context.

That is why the 701/5's will always be part of the overall plan as was always intended. Any thoughts that they are not required should be binned, they form an integral part of the wider capacity plan, not only for passenger capacity, but also for stabling reasons.

 

[NSEWonderer]

I really hope they remove the 450s from the Reading route soon.

== Doublepost prevention - post automatically merged: 15 Apr 2026 ==

Looks like it's the diagram which has 2J05/2J12 + 2F87/2G22 on it which changes over next week

I hope not. Love a little desiro run on a Reading with them vs a 458/4 And so do passengers often as the chance for all 4 toilets to be out is rare on a desiro than a 458/4 these days not to mention the occasional traction package being out making it effectively a 455 on notch 2 when starting.

 

[swr444]

I hope not. Love a little desiro run on a Reading with them vs a 458/4 And so do passengers often as the chance for all 4 toilets to be out is rare on a desiro than a 458/4 these days not to mention the occasional traction package being out making it effectively a 455 on notch 2 when starting.

If only other crews were good enough to keep them on time. Was waiting at Virginia water the other day on the up 2S and the up reading rocks up 4 minutes late.

 

[Peter Sarf]

Very true indeed. But without giving too much away here in relation to who was involved in the detailed planning of the SWT 10 car plan introduction (which didn't address all suburban services as is well known), much work was undertaken by many experienced railway people on the ground to maximise siding extensions and modifications, at every suburban location possible, including Wimbledon depot, Clapham Yard, Staines, Strawberry Hill, Guilford and Woking to maximise the number of sidings that could accommodate 10 car trains instead of 8 cars within the suburban area.

It was known at the time, that any further increase in 10 car formations post SWT days (as per the 701 plan) would not work within the stabling capacity that existed even after all that SWT work to accommodate all 10 car 458/5, 455/456 and 707 formations were up and running, and further stabling space would be required.

Feltham, I hear some shout ! A must have, and this was also looked in to many years ago in conjunction with BAA in relation to proposals for a new Airport service, along the Windsor side lines but this fell by the wayside for whatever reasons (lack of ££/realism etc possibly?), but even Feltham in todays incarnation (10 x 10 car roads) as welcome as it is, does not meet the needs of 10 car service provision in respect of the main suburban group of services, a large proportion of which have to be resourced from Wimbledon Depot Top Yard in order for the overall timetable plan to work.

It's a simple case of adequate pathways (for empty trains) when starting up the service each morning, combined with adequate stabling capacity for the formations concerned (10 car sidings), so as not to interfere unduly with neighbouring service groups, thus reducing risk to the overall plan if one such group suffers melt down on any occasion.

Feltham was a welcome addition to overall capacity needs, but in reality is in the wrong place - when taken against the pre 2017 timetable which was reasonably well balanced in respect of service provision each morning - ie: where empty trains came from to start up the service each day which had minimal impact on the passenger timetable.

I suspect there are still difficult decisions to be made in this matter, which will to some degree possibly impact on passenger capacity on some early (and late?) services, be that some shorter formations (ie 5 car 701) or possibly some services removed from the timetable to create pathways for additional empty moves to start the service up each day, particularly if pre covid service levels are to be re-implemented in a greater context.

That is why the 701/5's will always be part of the overall plan as was always intended. Any thoughts that they are not required should be binned, they form an integral part of the wider capacity plan, not only for passenger capacity, but also for stabling reasons.

Oh yes. The 701/5s were ordered as 5car for a reason as you so neatly describe above.

The only reason to explore using the 701/5s as fixed pairs up-thread was for the interim use covering a lack of all 701/0s being in service. Once all 701/0s are in service then the option of fixed pairs of 701/5s is gone. Anyway it looks like the interim use of fixed pairs of 701/5s would not have avoided the extra training/conversion-course. So only any use for convenience until all 701/0s are in service.

And I note the use of 701/5s before all 701/5s come in is only a (vague ?) possibility not a definite.

We will wait to see if the last of the 701/0s are so difficult that some 701/5s beat them into service.

 

[WrongRoad]

Ah, so more than just coupling/uncoupling then.

And prep, due to the two extra cabs and any extra checks/train management work that would need to be done

 

[43096]

I hope not. Love a little desiro run on a Reading with them vs a 458/4 And so do passengers often as the chance for all 4 toilets to be out is rare on a desiro than a 458/4 these days not to mention the occasional traction package being out making it effectively a 455 on notch 2 when starting.

Does a 458/4 with a traction pack out not behave like the 458/0 in the same situation then? i.e. the other two traction packs on the unit are cranked up to full rating to compensate.

 

[Andy1673]

Another main suburban diagram is introduced. The effective additional diagram starts and ends at Guildford, although it swaps at Waterloo after the first train with a current diagram to cycle units around.

Likely it will be so
5O01 off Strawberry Hill CSD then 2O01 then ex-450s 2J05-2J12-2F87-2G22-2M21-2M28-2F27-2F36-2G37-2G48-2F47-2F56-2G57-2G68-2M67-2M74-2D75 GLD - overnight ->
GLD 2D06 then 1D05-1D14 and so on
Pair of 450s 5J07 off Clapham Yard then 2J07-2J14 and so on
So there will be one new 701 diagram and pair of 450 released

 

[Class15]

I hope not. Love a little desiro run on a Reading with them vs a 458/4 And so do passengers often as the chance for all 4 toilets to be out is rare on a desiro than a 458/4 these days not to mention the occasional traction package being out making it effectively a 455 on notch 2 when starting.

But they can’t keep to time…

 

[TEW]

Likely it will be so
5O01 off Strawberry Hill CSD then 2O01 then ex-450s 2J05-2J12-2F87-2G22-2M21-2M28-2F27-2F36-2G37-2G48-2F47-2F56-2G57-2G68-2M67-2M74-2D75 GLD - overnight ->
GLD 2D06 then 1D05-1D14 and so on
Pair of 450s 5J07 off Clapham Yard then 2J07-2J14 and so on
So there will be one new 701 diagram and pair of 450 released

That's all correct.

 

[NSEWonderer]

If only other crews were good enough to keep them on time. Was waiting at Virginia water the other day on the up 2S and the up reading rocks up 4 minutes late.

Haha yeah some drivers don't appreciate how well the desiro brakes, you can get at nice stop without pushing it nor crawling at snails pace with them. I also find a decently on the ball guard does wonders.

== Doublepost prevention - post automatically merged: 15 Apr 2026 ==

But they can’t keep to time…

They can without overly pushing like crazy but yes you need a bit more things to go right with that being pretty much a quick wheelchair interval if any, on the ball guard and and driver that appreciates and is comfortable with Desiro braking. Indeed the 701s as a result with their superior acceleration after 15mph and better door speeds allows a more variety of driver ability to keep closer to time, but a 458 missing traction package aswell as often also have toilets out is arguably worse than the "slow" Desiro

 

[Big Jumby 74]

The only reason to explore using the 701/5s as fixed pairs up-thread was for the interim

It may pan out eventually that some /5's may effectively run as 10 car for long periods, subject to maintenance requirements, but until the overall stabling situation v proposed timetable is worked up in detail that won't be known.
I could waffle on about how stock cascades might be worked up by moving some a.m. start-up empty moves from Depot A to Depot B, which will then throw up spare capacity & pathways out of Depot A, which might be taken up by stock and moves from Depot C, which can't currently accommodate the requisite number of trains? But that's for another discussion.

== Doublepost prevention - post automatically merged: 16 Apr 2026 ==

you can get at nice stop without pushing it nor crawling at snails pace with them. I also find a decently on the ball guard does wonders.

It's also about confidence and prevailing conditions, especially for newbie drivers. For anyone (newbie drivers of 44 T road wagons etc) it will take time for them to build up confidence once out on their own. Everyone is different. Even seasoned drivers may take a while to adjust to a new traction type. All this applies to the back end as well of course.

 

[OneTrackMinded]

Funnily enough, the guess that 701/5s might run as fixed 10 car formations to begin with is correct:

The five-car trains, he tells MR, will start entering traffic towards the back of the summer. “We’re going to operate them in fixed formation as 10-cars to begin with. It gives us some flexibility to respond to demand because we’ve also got a duty
not to carry around too much fresh air.”

Establishing a secure connection ...

 

[wickham]

Funnily enough, the guess that 701/5s might run as fixed 10 car formations to begin with is correct:
View attachment 202441

Establishing a secure connection ...

As I suspected, but who is this "he" who has said this please ?

 

[OneTrackMinded]

As I suspected, but who is this "he" who has said this please ?

Lawrence Bowman, MD of SWR and NR Wessex.

 

[mansonlo49]

Funnily enough, the guess that 701/5s might run as fixed 10 car formations to begin with is correct:
View attachment 202441

Establishing a secure connection ...

quite funny，if use two 5 couples together why not just simply use a 10

 

[Goldfish62]

quite funny，if use two 5 couples together why not just simply use a 10

He's on the one hand saying they'll use 2x5 car units coupled together, then says he has a duty not to carry around fresh air. Doesn't quite make sense to me.

 

[OneTrackMinded]

He's on the one hand saying they'll use 2x5 car units coupled together, then says he has a duty not to carry around fresh air. Doesn't quite make sense to me.

It means they will use them to help with capacity during peak times.

 

[Big Jumby 74]

Funnily enough, the guess that 701/5s might run as fixed 10 car formations to begin with is correct:

If you are referring to my post (apologies if not ), but from my part not purely a 'guess' on my part, but an 'educated guess' based on my former professional knowledge of how service planning works.

quite funny，if use two 5 couples together why not just simply use a 10

As I mentioned up thread, there is simply not sufficient stabling capacity on the SW network for the entire suburban (701) fleet to run as fixed 10 car formations. There has to be flexibility to run some services as 5 car in order that the overall stabling of units each night fits within the overall available siding space at associated depots/locations.

It means they will use them to help with capacity during peak times.

Correct. That will form part of the plan I would think. There always was, and likely still is, some diagrams that only see visits to Waterloo in the shoulder peak times, and so might be candidates for 5 car only, which would also assist the overnight stabling issues to which I have commented above.

 

[43096]

Lawrence Bowman, MD of SWR and NR Wessex.

Who needs to get out and about to see what is actually going on on his patch.

Running new trains with “TfL Rail” on the PIS system is frankly shambolic.

 

[Stephen42]

And I note the use of 701/5s before all 701/5s come in is only a (vague ?) possibility not a definite.

We will wait to see if the last of the 701/0s are so difficult that some 701/5s beat them into service.

If there are 701/5s before all 701/0s it's likely to be very minimal on the 701/0 front. Plenty have come from store for considerable periods of time and entered service. The plan is to complete the 10-car rollout before doing the 5-cars (from the planning manager on SWR careers site):

Introducing the Arterios is a complex train planning challenge that involves prioritising the locations where their increased capacity is most needed, while carefully balancing this with the training of Drivers and Guards. We work closely with the Rostering, Fleet, and Operations and Safety Training Centre (OSTC) teams to ensure we produce a workable timetable that aligns with our train and traincrew availability. Once we’ve completed the ten-car roll out, we’ll be moving onto the introduction of the five-car units, which will require additional work.”

As others have mentioned, there will be plenty of five-car unit activities before they enter passenger service. Many of these will ideally happen before the 701/0 rollout is complete to avoid a long gap between the two. It's important not to over interpret any particular event or activity. Based on paths in the system so far it's plausible the next 701 delivery to Wimbledon might actually be 701/5(s) not a 701/0, should be clearer tomorrow night.

 

[NSEWonderer]

Does a 458/4 with a traction pack out not behave like the 458/0 in the same situation then? i.e. the other two traction packs on the unit are cranked up to full rating to compensate.

Well you also have to include that a 458/4 unlike a 458/0 is regeared to 100mph which makes starting acceleration differ to 458/0.

 

[nctd2306]

Well you also have to include that a 458/4 unlike a 458/0 is regeared to 100mph which makes starting acceleration differ to 458/0.

458/0s were geared for 100mph weren't they?
In my experience of/4s, they still keep to time on Reading and Windsor services pretty well, even with a motor out. I'd imagine it's the all stations round the Hounslow loop services where they struggle more.

 

[norbitonflyer]

Running new trains with “TfL Rail” on the PIS system is frankly shambolic.

Where do they say that? There is no intercghanghe between SWR and Crossrail/Elizabeth Line. (Although the SW London boroughs were all expected to pay for it, there are few, if any, journeys from this part of the world which can make use of the new core. Other than to ride it when it was new, for track-bashing completeness, I can count on the fingers of one foot the number of times I have made use of it).

 

[adelante_burns]

Where do they say that? There is no intercghanghe between SWR and Crossrail/Elizabeth Line. (Although the SW London boroughs were all expected to pay for it, there are few, if any, journeys from this part of the world which can make use of the new core. Other than to ride it when it was new, for track-bashing completeness, I can count on the fingers of one foot the number of times I have made use of it).

The PIS shows a page with status updates for all TfL services, regardless of whether there are stations on the SWR network that have interchange with them.

 

[WimFit]

Well you also have to include that a 458/4 unlike a 458/0 is regeared to 100mph which makes starting acceleration differ to 458/0.

The 458/0’s were geared exactly the same as the 458/4’s are.

 

[TT-ONR-NRN]

Where do they say that? There is no interchange between SWR and Crossrail/Elizabeth Line. (Although the SW London boroughs were all expected to pay for it, there are few, if any, journeys from this part of the world which can make use of the new core. Other than to ride it when it was new, for track-bashing completeness, I can count on the fingers of one foot the number of times I have made use of it).

Well there is, at Reading.

 

[absolutelymilk]

Who needs to get out and about to see what is actually going on on his patch.

Running new trains with “TfL Rail” on the PIS system is frankly shambolic.

Presumably he has decided to prioritise getting the rest of the 701s into service before minor tweaks to the PIS, which seems like a reasonable decision.