Class 175 future speculation

[Wolfie]

Because the 197s are replacing the 175s,so it makes most sense for them to also take over the depot. There will no longer be any use for the 175s in Chester, so why keep then based there?

Exactly. The alternative would be the tail wagging the dog.

 

[skyhigh]

All of this could have been prevented if CAF just built their own depot for the 197s.

Right, so more expense for the contract to set up a brand new depot and staff it just so 175s can stay at the existing depot, which may be nowhere near where they end up operating (or indeed, they may go nowhere else but scrap). That sounds sensible...

Surely Siemens Ardwick could take on the maintenance or at least some of it if there is space, considering how well they maintain the 185s which are similar trains?

'Similar' as in the class numbers are 1x5?

Different manufacturers, different engines, different transmissions, different coupler, different TMS for a start...

 

[507020]

Right, so more expense for the contract to set up a brand new depot and staff it just so 175s can stay at the existing depot, which may be nowhere near where they end up operating (or indeed, they may go nowhere else but scrap). That sounds sensible...

If we’re being sensible, the idea is they won’t be going for scrap…

'Similar' as in the class numbers are 1x5?

Different manufacturers, different engines, different transmissions, different coupler, different TMS for a start...

A small fleet of 3 car 100mph DMUs, which both formerly operated the Blackpool North, Barrow-in-Furness and Windermere services, so they are clearly suitable for similar work.

 

[Starmill]

Right, so more expense for the contract to set up a brand new depot and staff it just so 175s can stay at the existing depot, which may be nowhere near where they end up operating (or indeed, they may go nowhere else but scrap). That sounds sensible...

Indeed. Was taking over Chester not a central part of of the agreement with CAF too? They could have simply said no deal to the Welsh Government if it had been taken off the table. Or more likely they would have pushed back new train delivery dates if they'd had to wait around for construction of a new depot from scratch.

 

[zwk500]

If we’re being sensible, the idea is they won’t be going for scrap…

Just to poke the bear, why is it impossible for scrapping them to be a sensible idea?

A small fleet of 3 car 100mph DMUs, which both formerly operated the Blackpool North, Barrow-in-Furness and Windermere services, so they are clearly suitable for similar work.

So because it's suitable for similar work the Siemens guys should be able to maintain an Alstom product? It's not like taking a Ford Focus to your nearest garage.

 

[Starmill]

If we’re being sensible, the idea is they won’t be going for scrap…

Why is it more or less sensible to keep older trains in service? Haven't there been myriad cases where older trains were used for a long time beyond the end of their serviceable life, thus costing more in maintenance than new builds in maintenance and depreciation would have? 142s, 317s, 313s and 315s are all having or had large sums spent on them in their final few years of service. 175s aren't as old, of course, so the numbers may yet add up differently. But is it impossible to believe that they wouldn't?

 

[507020]

Just to poke the bear, why is it impossible for scrapping them to be a sensible idea?

It is impossible due to the lack of electrification in this country necessitating the continued use of Diesel, while simultaneously any commitment to the continued use of Diesel for 40 years by the procurement of new pure DMUs is increasingly unacceptable (and also difficult as more manufacturers ditch the capability to produce them)

The most sensible idea would be for them to be imposed on a random operator which is in need of DMUs at the expense of fleet standardisation, but that would require the issue of an Alstom depot to be resolved. Perhaps just some consideration should have been given to the future of the 175s during the procurement of the 197s.

So because it's suitable for similar work the Siemens guys should be able to maintain an Alstom product? It's not like taking a Ford Focus to your nearest garage.

I’m sure Ardwick also maintains 323s, which are also not a Siemens product. This was also a purpose built depot for 185s, rather than taking over Chester. The issue is that a Ford Focus is one of the most common cars in Britain, so the likelihood of your nearest garage being a Ford garage capable of maintaining them is quite high. The 175s are a non-standard fleet.

Why is it more or less sensible to keep older trains in service? Haven't there been myriad cases where older trains were used for a long time beyond the end of their serviceable life, thus costing more in maintenance than new builds in maintenance and depreciation would have? 142s, 317s, 313s and 315s are all having or had large sums spent on them in their final few years of service. 175s aren't as old, of course, so the numbers may yet add up differently. But is it impossible to believe that they wouldn't?

Continued use of 142s was just egregious, I dare say even as early as 1990. Perhaps if more 175s had been ordered to replace them, there would be less of a problem today. I don’t think the situation with the PEPs is comparable, with them being electrics. Obviously running a 45+ year old fleet not ideal, but they do remain serviceable and surprisingly reliable. There should be more urgency in removing 153s and 155s than 313s, despite them being 10 years newer.

 

[MattRat]

If we’re being sensible, the idea is they won’t be going for scrap…

A small fleet of 3 car 100mph DMUs, which both formerly operated the Blackpool North, Barrow-in-Furness and Windermere services, so they are clearly suitable for similar work.

Aren't some of those now run by 195s? Might be a bit of a backwards stock change, but freeing up 195s would help get rid of more Sprinters.

 

[Philip]

So because it's suitable for similar work the Siemens guys should be able to maintain an Alstom product? It's not like taking a Ford Focus to your nearest garage.

Whilst the mechanical aspects between 175 and 185 aren't identical, they are similar because both use hydraulic transmission and have similar engines. They are more closely related to each other than they are to Sprinters or Voyagers. Siemens engineers would need to be trained on the maintenance for a different train type but once that is done I think they should be fairly competent. We already know that they provide an excellent maintenance for the 185s and I reckon they could take on the workload of maintaining or partly maintaining the 175s, particularly now that more 185s are sticking to eastern routes and spending more depot time at York/Cleethorpes and less at Ardwick.

 

[43096]

The most sensible idea would be for them to be imposed on a random operator which is in need of DMUs at the expense of fleet standardisation, but that would require the issue of an Alstom depot to be resolved. Perhaps just some consideration should have been given to the future of the 175s during the procurement of the 197s.

Why do they have to be maintained by Alstom? There's plenty of fleets that are maintained by the TOC.

I’m sure Ardwick also maintains 323s, which are also not a Siemens product.

Ardwick don't maintain the 323s, they're based at Allerton (having previously been maintained at Longsight).

 

[LOL The Irony]

Just to poke the bear, why is it impossible for scrapping them to be a sensible idea?

Because there's a shortage of DMUs caused by, among other things, poor electrification strategy dating back to the implementation of the modernisation plan.

 

[Energy]

If we’re being sensible, the idea is they won’t be going for scrap…

A small fleet of 3 car 100mph DMUs, which both formerly operated the Blackpool North, Barrow-in-Furness and Windermere services, so they are clearly suitable for similar work.

You're assuming their future work is near to Chester, if they are replacing trains instead of supplementing them there will be space wherever they go.

 

[BayPaul]

The most sensible idea would be for them to be imposed on a random operator which is in need of DMUs at the expense of fleet standardisation, but that would require the issue of an Alstom depot to be resolved. Perhaps just some consideration should have been given to the future of the 175s during the procurement of the 197s.

They don't need to be maintained by alstom. But equally, there's no reason why alstom couldn't take over or build a depot in their new home.
There's a weird attitude on railforums that the network is run to find homes for trains, rather than the other way around. I suspect that a home will be found for them (my guess is Chiltern, allowing some 168s to be converted to 170s for cascade to Northern or EMR), but if not, then I'm sure that the reason is that it is better and more cost effective for us as taxpayers to scrap them.

 

[507020]

Because there's a shortage of DMUs caused by, among other things, poor electrification strategy dating back to the implementation of the modernisation plan.

Beeching of course came along only 6 years after the modernisation plan, so he is likely more to blame for this than the eponymous closures.

You're assuming their future work is near to Chester, if they are replacing trains instead of supplementing them there will be space wherever they go.

My assumption is that they’re most likely to work services where they’re already cleared, which would logically mean Northern services from Chester - Leeds and the Mid Cheshire Line, among others in the North West, which might free up 195s for some more frequent stopping services, but I’d bet on them supplementing, rather than replacing existing DMUs. There is a shortage after all.

They don't need to be maintained by alstom. But equally, there's no reason why alstom couldn't take over or build a depot in their new home.
There's a weird attitude on railforums that the network is run to find homes for trains, rather than the other way around. I suspect that a home will be found for them (my guess is Chiltern, allowing some 168s to be converted to 170s for cascade to Northern or EMR), but if not, then I'm sure that the reason is that it is better and more cost effective for us as taxpayers to scrap them.

It would be nice if they could be maintained by Alstom alongside Aventras, or other ex-Bombardier stock, if that could happen somewhere. The 175s are more suitable for Northern than 170s and would be a non-standard type for Chiltern, which isn’t as much a problem for Northern.

It would be more cost effective for the taxpayer to have blanket electrification and not be handing out dividends to shareholders and foreign railways, but still.

 

[skyhigh]

I’m sure Ardwick also maintains 323s

They don't.

== Doublepost prevention - post automatically merged: 13 Nov 2022 ==

A small fleet of 3 car 100mph DMUs, which both formerly operated the Blackpool North, Barrow-in-Furness and Windermere services, so they are clearly suitable for similar work.

I was commenting on the way it was said 185s were similar to 175s on a maintenance level, not on a suitability for certain work

== Doublepost prevention - post automatically merged: 13 Nov 2022 ==

Siemens engineers would need to be trained on the maintenance for a different train type but once that is done I think they should be fairly competent.

They would be as competent as any fitters trained on new stock. They may have a little helpful knowledge, but the differences between the 2 types will be pretty major.

 

[Elecman]

The train wash and under frame wash at Chester depot are programmed uniquely for the 175s not sure if anyone would be able to reprogram them for different units

== Doublepost prevention - post automatically merged: 13 Nov 2022 ==

Siemens don’t maintain any 323s at Ardwick they are done by Alstom at Longsight

 

[LOL The Irony]

Siemens don’t maintain any 323s at Ardwick they are done by Alstom at Longsight

I was under the impression that 323s were being done in house at Allerton, unless things have changed (again).

 

[Rhydgaled]

Is an Alstom depot even necessary?

Good question. I understand that Alstom is contracted to do maintainance and provide a certain number of units ready for service each day. Is that contract with the TOC who runs the class 175s or with the ROSCO that owns them? If the former, does the contract expire with the lease or does it transfer to another party? If the latter, then presumably maintainance would need to remain at an Alstom depot unless there is some other way to terminate the maintainance contract with Alstom.

Why is it more or less sensible to keep older trains in service? Haven't there been myriad cases where older trains were used for a long time beyond the end of their serviceable life, thus costing more in maintenance than new builds in maintenance and depreciation would have? 142s, 317s, 313s and 315s are all having or had large sums spent on them in their final few years of service. 175s aren't as old, of course, so the numbers may yet add up differently. But is it impossible to believe that they wouldn't?

Financial resources aren't the only resources that should be considered, but all too often it seems that financial considerations trump consideration of natural resources. A fair bit of energy is required to build a new train. For example:

Manufacturing the Aventras for SWR will produce around 500,000 tonnes of CO2, which is 18% of the annual emissions from all the electric trains in the UK for one year.

According to Wikipedia, there are / will be 90 class 701s and there are around 2,500 EMUs in the British fleet, so the 701s represent only about 3.5% of the EMU fleet in terms of number of units.

The most sensible idea would be for them to be imposed on a random operator which is in need of DMUs at the expense of fleet standardisation, but that would require the issue of an Alstom depot to be resolved. Perhaps just some consideration should have been given to the future of the 175s during the procurement of the 197s.

Choosing a recipient at random doesn't sound at all sensible to me, but neither does scrapping them. The sensible thing would be to make a list of routes which are not electrified and they would provide a better service than the current outlook, and then to evaluate each to see which would be the best option (biggest benefits / most practical maintainance arrangements etc.) and go with that option. I can't help with selecting the best option, but the list could look something like this:

• GWR (Cardiff-Portsmouth as 5-car sets)
• Northern (various possibilities)
• XC/WMR (Cardiff-Nottingham and Birmingham-Hereford) bit of a curve-ball this one, and there might not be quite enough 175s to make it work, but the idea would be to do some franchise remapping so that the Birmingham-Nottingham/Leicester locals currently run by XC would become WMR/EMR services using 196s released from the BMN-HFD route
• TfW (any combination of MAN-SWA (until electrification to Swansea, CDF-Pembrokeshire, the Heart Of Wales and/or fast services along the North Wales coast - the main problem with them here is they are spread too thinly around W&B, take them off some routes to allow them to be paired up on others and they'd be an improvement over the current/planned 150s,153s, 197s and single 175s on these routes)
• TPE (particularly the Cleethorpes route, but all depends on timing of the electrification of the main TPE core) to release 185s to Northern to help get rid of 150s.
• EMR (if Liverpool-Norwich is still going to be split so that portion working is no longer required; or lengthened to 5/6-cars throughout)

Might be a bit of a backwards stock change, but freeing up 195s would help get rid of more Sprinters.

It very much depends on the route in question. I'm sure there is some stuff that the 195s work where a 175 would be more-appropriate, and equally there are probably some services which are better off staying with 195s. For example, what's working York-Blackpool at the moment? If it's 195s, then perhaps that could be a good one for 175s to take over and push 195s onto the remaining 150-operated diagrams through Warrington Central (and similar services elsewhere).

 

[Starmill]

Financial resources aren't the only resources that should be considered, but all too often it seems that financial considerations trump consideration of natural resources.

Sure, there's the embodied carbon to consider and that's of significant importance. However trains generally achieve much better recycling rates than most consumer goods so focusing on end of life trains is a really poor way to reduce our use of rare elements or carbon emissions. Trains cannot reasonably work for more than around forty years without the replacement costing more in carbon long term.

 

[RobShipway]

Good question. I understand that Alstom is contracted to do maintainance and provide a certain number of units ready for service each day. Is that contract with the TOC who runs the class 175s or with the ROSCO that owns them? If the former, does the contract expire with the lease or does it transfer to another party? If the latter, then presumably maintainance would need to remain at an Alstom depot unless there is some other way to terminate the maintainance contract with Alstom.


Financial resources aren't the only resources that should be considered, but all too often it seems that financial considerations trump consideration of natural resources. A fair bit of energy is required to build a new train. For example:

According to Wikipedia, there are / will be 90 class 701s and there are around 2,500 EMUs in the British fleet, so the 701s represent only about 3.5% of the EMU fleet in terms of number of units.


Choosing a recipient at random doesn't sound at all sensible to me, but neither does scrapping them. The sensible thing would be to make a list of routes which are not electrified and they would provide a better service than the current outlook, and then to evaluate each to see which would be the best option (biggest benefits / most practical maintainance arrangements etc.) and go with that option. I can't help with selecting the best option, but the list could look something like this:

• GWR (Cardiff-Portsmouth as 5-car sets)
• Northern (various possibilities)
• XC/WMR (Cardiff-Nottingham and Birmingham-Hereford) bit of a curve-ball this one, and there might not be quite enough 175s to make it work, but the idea would be to do some franchise remapping so that the Birmingham-Nottingham/Leicester locals currently run by XC would become WMR/EMR services using 196s released from the BMN-HFD route
• TfW (any combination of MAN-SWA (until electrification to Swansea, CDF-Pembrokeshire, the Heart Of Wales and/or fast services along the North Wales coast - the main problem with them here is they are spread too thinly around W&B, take them off some routes to allow them to be paired up on others and they'd be an improvement over the current/planned 150s,153s, 197s and single 175s on these routes)
• TPE (particularly the Cleethorpes route, but all depends on timing of the electrification of the main TPE core) to release 185s to Northern to help get rid of 150s.
• EMR (if Liverpool-Norwich is still going to be split so that portion working is no longer required; or lengthened to 5/6-cars throughout)

It very much depends on the route in question. I'm sure there is some stuff that the 195s work where a 175 would be more-appropriate, and equally there are probably some services which are better off staying with 195s. For example, what's working York-Blackpool at the moment? If it's 195s, then perhaps that could be a good one for 175s to take over and push 195s onto the remaining 150-operated diagrams through Warrington Central (and similar services elsewhere).

I don't believe that Liverpool - Norwich is going to be split now. With regards to TPE, I believe that is a none starter. It would be more likely that the class 175 units go to Northern to replace the class 150 units.

I cannot see GWR replacing class 165/166 units on Cardiff - Portsmouth route. If they went to GWR, they could go to replace some of the class 158 units and the class 150 units.

 

[61653 HTAFC]

TPE (particularly the Cleethorpes route, but all depends on timing of the electrification of the main TPE core) to release 185s to Northern to help get rid of 150s.

If getting rid of 150s is the aim, why involve the heavy, thirsty 185s at all? Surely you'd just use the 175s and an internal cascade?
185s to Northern is just the suggestion that refuses to die. DfT would have an aneurysm at the thought of having to subsidise the additional fuel and track access costs!

 

[Rhydgaled]

Trains cannot reasonably work for more than around forty years without the replacement costing more in carbon long term.

Yes, trains will generally need to be replaced after 35-40 years of service, but the 175s are only just passing 20 years in service so they've got a good bit of life left in them yet. We're talking 2035-2040 before they need replacement.

I cannot see GWR replacing class 165/166 units on Cardiff - Portsmouth route. If they went to GWR, they could go to replace some of the class 158 units and the class 150 units.

Why not? Unless there are still places on the GWR network where the 166s/165s cannot go it would seem that the 16x (released from the Portsmouth route) would be better suited to the sort of local stopping work that 150s are suited too than the class 175s with their end doors which are most suitable for long-distance inter-urban (regional express) services like Cardiff-Portsmouth or lengthy regional/rural routes like the Heart Of Wales where most stations have very few passengers.

If getting rid of 150s is the aim, why involve the heavy, thirsty 185s at all? Surely you'd just use the 175s and an internal cascade?
185s to Northern is just the suggestion that refuses to die. DfT would have an aneurysm at the thought of having to subsidise the additional fuel and track access costs!

There are alot more 185s than there are 175s. Even the class 185 fleet is not suffiicent (in terms of number of units, it might be in terms of capacity given the 185s are all 3-car and 23m long vehicles rather than the 20m of class 150s) to replace all 78 Northern class 150s. That's why I said it would also depend on the timing of TransPennine electrification; when the core is done TPE will only have the Clethorpes route plus 1tph to each of Saltburn, Scarborough and Hull that require diesel traction. There is no way they will still need 51 straight DMUs (the 185s) at that point so rather than split the fleet why not send all the 185s away and bring in new EMUs (my vote goes to additional 397s, but in longer formations and with better seats) and a smaller diesel fleet (the 175s)? If they cut the Cleethorpes services back to Piccadilly (rather than cutting across through Castlefield and on to Liverpool) and could get availability of the Nova fleets in the right place they might even be able to run all of that with just the 802s and mark 5s in which case Northern could have all the 185s plus the 175s. Also, giving Northern the 185s once TPE is finished with them keeps them in the same sort of area meaning there might not be the issue of having to find somewhere else to maintain them.

 

[61653 HTAFC]

Yes, trains will generally need to be replaced after 35-40 years of service, but the 175s are only just passing 20 years in service so they've got a good bit of life left in them yet. We're talking 2035-2040 before they need replacement.


Why not? Unless there are still places on the GWR network where the 166s/165s cannot go it would seem that the 16x (released from the Portsmouth route) would be better suited to the sort of local stopping work that 150s are suited too than the class 175s with their end doors which are most suitable for long-distance inter-urban (regional express) services like Cardiff-Portsmouth or lengthy regional/rural routes like the Heart Of Wales where most stations have very few passengers.


There are alot more 185s than there are 175s. Even the class 185 fleet is not suffiicent (in terms of number of units, it might be in terms of capacity given the 185s are all 3-car and 23m long vehicles rather than the 20m of class 150s) to replace all 78 Northern class 150s. That's why I said it would also depend on the timing of TransPennine electrification; when the core is done TPE will only have the Clethorpes route plus 1tph to each of Saltburn, Scarborough and Hull that require diesel traction. There is no way they will still need 51 straight DMUs (the 185s) at that point so rather than split the fleet why not send all the 185s away and bring in new EMUs (my vote goes to additional 397s, but in longer formations and with better seats) and a smaller diesel fleet (the 175s)? If they cut the Cleethorpes services back to Piccadilly (rather than cutting across through Castlefield and on to Liverpool) and could get availability of the Nova fleets in the right place they might even be able to run all of that with just the 802s and mark 5s in which case Northern could have all the 185s plus the 175s. Also, giving Northern the 185s once TPE is finished with them keeps them in the same sort of area meaning there might not be the issue of having to find somewhere else to maintain them.

There's an awful lot of ifs and buts in there. Both the 175s and 185s might struggle for work once they're displaced from their current roles. Not sure which will fare better really, the Coradias are probably cheaper to lease and definitely cheaper to run, but the 185s are less likely to burst into flames!

I also don't think getting rid of the 150s at Northern is a priority, and doesn't need to be. Sure, they're the oldest DMUs so you'd expect them to be next on the chopping block- but they also have some advantages- doors at thirds, 20m vehicles, etc. which make them worth keeping going as long as possible. A number of routes have had platforms extended on the assumption of 20m vehicles, so using anything else means shortforming or use of SDO.

 

[tbtc]

100mph end doored 175s wouldn’t be a suitable replacement for the duties that 150s operate, given that they are generally those where the “mid doors” and good acceleration is more necessary than “fast” running

It’s easy to say that Northern don’t have enough DMUs, but if anything they have plenty of 90/100 mph units (158/ 170/ 195), so that these trains end up deputising for 150s on stoppers, since the real problem is the shortage of unremarkable units for the unremarkable “local” services that make up the bulk of the franchise (the kind of duties that 142/144/ 153s did)

Meanwhile, being enthusiasts, the Forum seems more interested in “My Ideal Stock For The Settle & Carlisle/ Windermere Lines” than more practical trains for the likes of stoppers through Rotherham/ Halifax/ Atherton (even though these towns make up the backbone of the Northern operation)

But the idea of these cascades will never die, to an outsider it no doubt feels like an upgrade, in the same way that people will always suggest four coach Voyagers replace the coach Turbostars on routes like Nottingham to Cardiff

when the core is done TPE will only have the Clethorpes route plus 1tph to each of Saltburn, Scarborough and Hull that require diesel traction. There is no way they will still need 51 straight DMUs (the 185s) at that point so rather than split the fleet why not send all the 185s away and bring in new EMUs (my vote goes to additional 397s, but in longer formations and with better seats) and a smaller diesel fleet (the 175s)?

If they cut the Cleethorpes services back to Piccadilly (rather than cutting across through Castlefield and on to Liverpool) and could get availability of the Nova fleets in the right place they might even be able to run all of that with just the 802s and mark 5s in which case Northern could have all the 185s plus the 175s

I can’t understand why your preferred solution (once the TPE line is fully wired) is

*- pure diesel 100mph 175s running under the wires from Liverpool/ Manchester Airport up the fast ECML to Northallerton (or turning off at York/ Micklefield)
*- bi-mode 125 802s running a truncated Manchester to Cleethorpes service that barely sees any electrification infrastructure east of Hazel Grove (just a token section at Doncaster station, not worth putting the pantograph up for) and no fast running

(Given the surplus of stock at TPE, their regular cancellations, and the capacity issues that sister company Lumo seem to be having, I wouldn’t be surprised if people start talking about some of the 802s moving to the Open Access firm, but that’s shorter story for another thread)

 

[507020]

(Given the surplus of stock at TPE, their regular cancellations, and the capacity issues that sister company Lumo seem to be having, I wouldn’t be surprised if people start talking about some of the 802s moving to the Open Access firm, but that’s shorter story for another thread)

Now this would be good, if they received a Lumo interior and they were replaced at TPE with more 397s.

 

[skyhigh]

There are alot more 185s than there are 175s. Even the class 185 fleet is not suffiicent (in terms of number of units, it might be in terms of capacity given the 185s are all 3-car and 23m long vehicles rather than the 20m of class 150s) to replace all 78 Northern class 150s.

Heavy, fuel thirsty, different vehicle length 185s are in no way a suitable replacement for 150s. The cost of operating those services will go through the roof (and I would be willing to bet 185s would be more expensive on both a lease and running cost front than 195s).

 

[Bletchleyite]

Heavy, fuel thirsty, different vehicle length 185s are in no way a suitable replacement for 150s. The cost of operating those services will go through the roof (and I would be willing to bet 185s would be more expensive on both a lease and running cost front than 195s).

185s are no use as a direct replacement for 150s, no. The only thing they have in common is the door placement.

What are good as a direct replacement for 150s, though, is 195s, and they're demonstrating this by their use on east Manchester commuter services.

Where 185s or 175s could come in handy here is that by being put on services presently operated by 195s that don't carry heavy loadings, they can allow a cascade to free up those 195s. You can't do that with anything else Northern has, as the WCML services have to be operated using 100mph units because the paths are no longer for 75mph or 90mph. So you can't just drop 156s or 158s on the Barrows or Windermeres to get the 195s, but you could use 175 or 185s. Both classes have done that before.

Then you've got services operated using 150s that don't need to be operated using 150s because they don't get crowded. Ormskirk-Preston-Colne-Blackpool S uses 150s sometimes, but 156s or 158s are fine on those, for instance.

Atherton meanwhile is crying out for 195s (and sometimes has some, there's one 3 car out there today, I just looked). It's basically the same as the Birmingham Snow Hill lines - quiet at one end (Kirkby), really busy at the other, and with lots of stops. Barring electrification, 195s are perfect.

 

[Rhydgaled]

100mph end doored 175s wouldn’t be a suitable replacement for the duties that 150s operate, given that they are generally those where the “mid doors” and good acceleration is more necessary than “fast” running

That's what I was trying to say regarding GWR, where the 165s/166s with 'doors at thirds' would be a better fit as 150s replacements (not sure what their acceleration is like though).

It’s easy to say that Northern don’t have enough DMUs, but if anything they have plenty of 90/100 mph units (158/ 170/ 195), so that these trains end up deputising for 150s on stoppers, since the real problem is the shortage of unremarkable units for the unremarkable “local” services that make up the bulk of the franchise (the kind of duties that 142/144/ 153s did)

I would argue that the 195s are "unremarkable units for the unremarkable 'local' services" - yes they have a 100mph top speed but that seems to apply to almost all new heavy-rail stock that isn't a 125mph IC unit these days (the TfW FLIRTs are the only exception that comes to mind).

people will always suggest four coach Voyagers replace the coach Turbostars on routes like Nottingham to Cardiff

Not me at the moment (my suggestion for that route is 5-car class 222s, with first class reduced or removed entirely).

I can’t understand why your preferred solution (once the TPE line is fully wired) is

Because that isn't my preferred solution at all. Sorry, I cannot have worded my previous post clearly enough. By "run all of that with just the 802s and mark 5s" I meant the Saltburn, Scarborough, Hull and Cleethorpes services. The rest of TPE's services could and should be worked by straight EMUs once the core TPE route between Manchester and York is wired. To clarify, my prefered solution for TPE (once Manchester-York is wired and ignoring the stoppers (most of which terminate (or used to) at Huddersfield) which I think should be run by Northern) is:

• class 802s on all Hull services, plus as many of the Scarboroughs and Saltburns as possible (ideally they would cover all of them, but I doubt there are quite enough)
• class 68s with mark 5 on Manchester Piccadilly - Cleethorpes services, plus any of the Scarborough/Saltburn diagrams that cannot be handled by 802s
• straight EMUs (397s with better seats) on everything else

However, if there aren't quite enough 802s and mark 5 sets to cover that (which is likely if the Cleethorpes services aren't truncated to Piccadilly), then that's where the 175s could step in (primarily on the Cleethorpes route). Not sure what happens to the mark 5 sets in that case.

Manchester to Cleethorpes service that barely sees any electrification infrastructure east of Hazel Grove (just a token section at Doncaster station, not worth putting the pantograph up for) and no fast running

That's why I would stick the 175s (or mark 5 sets) on it, although the MML wiring scheme would also provide OHLE between Dore & Totley and Sheffield and perhaps beyond (is a link from Sheffield to the ECML currently included in the MML scheme?) that is probably still less wires than many of the other places the 175s (or mark 5s with 68s) could be used.

Heavy, fuel thirsty, different vehicle length 185s are in no way a suitable replacement for 150s.

I presume 185s have better acceleration than 170s? However, in most cases what I meant was for 185s to replace 195s on routes like Manchester-Barrow with the 150s actually being replaced by the cascaded 195s (the same is true of my suggestion of 175s on Blackpool-York, cascade the 195s (which ARE suituable replacements for 150s, provided the 150s are being used in places where they themselves are suitable) to replace the 150s).

 

[Bletchleyite]

Mk5 sets are going to be used on the Cleethorpes.

 

[warwickshire]

Possible 175 could even go to gwr to replace the Castle hsts even.
Maybe 175 might even go to Northern on the Barrow/Windermere. Manchester routes to Sheffield. Possible Manchester to Liverpool or Manchester to Chester routes. Especially if Longsight keeps them. So to push all 195 east. Ie Sheffield and Leeds side. A Including replacement of the 158 on Wigan to Leeds so these can replace the 155 at Hull. Then 150 released from Manchester areas capacity elsewhere.
However potential use for Northern with Longsight being a potential depot there.