IEP and the Cotswold line

[The Ham]

You don't need to buy one.

Remember, IEP is being delivered under this new-fangled 'all-in-one' contract, where (grossly simplified) Agility own and maintain the trains and just have to make available the units you request.

So where, you have previously contracted for 7-car units, you change that to 8-car or 9-car etc... up to 12-car units (which is the max length in the specs).

I think that you've perhaps over simplified things; as what happens when all 598 IEP coaches are allocated and a TOC requests an extra coach?

Also as IEP coaches are 26m long a 12 car unit would be 312m long (or about 50m longer than the current 11 coach Pendolinos), which may cause problems at certain key stations.

 

[transmanche]

I think that you've perhaps over simplified things; as what happens when all 598 IEP coaches are allocated and a TOC requests an extra coach?

I think you are overcomplicating things. Agility are contracted to make the units/vehicles available - how they do that is up to them.

Also as IEP coaches are 26m long a 12 car unit would be 312m long (or about 50m longer than the current 11 coach Pendolinos), which may cause problems at certain key stations.

Tell that to DfT - they're the ones setting the specs.

 

[Monkey Magic]

You did put words in my mouth - I have always very carefully qualified different formations as being a possibility and no more than that - never that it will happen, in this thread and others.

Maybe I did read too much into the 'only person' bit but to my mind it clearly implied some doubt about what I was saying, perhaps understandably when many people continue to post here on the basis that the GW IEP fleet that emerges in 2017-18 will be exactly what DfT has indicated it wants - even though the ITT clearly demonstrated that it was willing to listen to a detailed case from an operator to be allowed to have other formations - and that issue clearly came up in the pre-qualifying process before the ITT was finalised.

I may have misunderstood you, however, I did not put words into your mouth.

There is a great deal of differing information about IEP which is obviously why people are drawing differing conclusions about likely outcomes.

The discussion of IEP in last months Modern Railway included calculations for an 8 car bi-mode to Hereford, but everything else was on the basis of 5 car bi-mode. Including the section on standing waves with the pantograph up was on the basis of 5 car bi-mode. I assumed that the 8 car calculations had been made prior to the change in the order.

The recent CLPG article was based on 5 car IEP and they normally have good relations with FGW regarding route so it is surprising that no mention was made there about the possibility of longer formations. Multiple working was considered and discounted.

The Cotswold line with its Short platforms, single track and very heavy use during peak hours that make for some interesting problems but ones that I've not seen discussed very much.

 

[Mintona]

I've always thought that they should all be 9 coaches long. I can't see any reason that this wouldn't work, and I have no idea why it's not being done. Platform lengthening would be useful but not essential as long as SDO is fitted.

 

[jimm]

I may have misunderstood you, however, I did not put words into your mouth.

You seem to have trouble remembering what you wrote back up the thread in post No 16 at the top of page 2.

It says

your posts are the only comments anywhere I've seen that have said that there can (and will be) alternative formations of Bi-mode

I repeat, I have never said, in this thread or a couple of others, that there will be alternative formations, just that there could be and that the DfT has set out how this could potentially happen, should an operator want to ask for it.

Could be, not will be - there is a difference.

Nor have I drawn any conclusions, just stated that the fleet that eventually takes to the tracks may not be the one that currently forms the basis of DfT's agreement with Agility.

I wouldn't read too much into what appeared in the CLPG newsletter. If the author was unaware of the range of possibilities offered by the IEP's selective door opening system in single unit or multiple-unit formations suggested back up the thread by cjp and The Ham - ie that you stop with part of one five-car set and part of the other on a four of five-car length platform (a possibility I myself hadn't really considered but which seems the only plausible way to go if all the bi-modes do end up as five-car sets, given the many platforms across the GW routes that are not anything like 260m long) then they could cheerfully have written all sorts of stuff in blissful ignorance.

I've always thought that they should all be 9 coaches long. I can't see any reason that this wouldn't work, and I have no idea why it's not being done. Platform lengthening would be useful but not essential as long as SDO is fitted.

Here's a reason - because off-peak traffic past Oxford to Worcester and past Swindon to Gloucester and Cheltenham, to name but two examples on routes IEP will be used on, is unlikely to ever justify use of a train with 627 seats - that is the equivalent of two Class 180s with another 60-odd seats on top.

If current growth rates in passenger traffic are maintained, the extra capacity a five-car IEP offers over a 180 may already be used up by the time IEP appears - hence FGW's concerns over an all-five-car bi-mode fleet - but you won't ever make a nine-car set pay off-peak to those destinations. FGW tried running HSTs on lots of off-peak Cotswold services in 2009 after withdrawing the 180s but quickly brought back 166s to bring capacity and costs back into line, albeit at the cost of passenger comfort.

 

[Mintona]

I'm currently wedged in the corner of an 8 coach HST that has come from Cheltenham and is now somewhere near Didcot. I look forward to this being reduced to 5 coaches in the future, providing the people of Kemble and Swindon no opportunity to board the train.

Does it really matter if not all trains are full at all times?

 

[Dave1987]

I'm currently wedged on an 8 coach HST that has come from Cheltenham and now somewhere near Didcot. I look forward to this being reduced to 5 coaches in the future.

Does it really matter if not all trains are full at all times?

This pretence that intercity services only need to be full strength during the weekday is what is causing all the issues. All intercity services need to be full strength at all times. Enough with this 2 x 5 car rubbish.

 

[jimm]

I'm currently wedged in the corner of an 8 coach HST that has come from Cheltenham and is now somewhere near Didcot. I look forward to this being reduced to 5 coaches in the future, providing the people of Kemble and Swindon no opportunity to board the train.

Does it really matter if not all trains are full at all times?

This pretence that intercity services only need to be full strength during the weekday is what is causing all the issues. All intercity services need to be full strength at all times. Enough with this 2 x 5 car rubbish.

Who said it would be reduced to five coaches? At busy times, seven days a week, a 2x5-car formation will be used throughout, same as HSTs work Saturday morning into London and back in the late afternoon and early evening now and go out to Hereford and Cheltenham on Sunday to work afternoon and early evening trains back to London. At other times of the weekend, FGW splits and joins Turbo formations at Oxford to balance loadings and seating capacity to the east and west.

At quieter times of the day, when trains split and join at Swindon, the Swindon passengers will have a 315-seat five-car train of their very own to board and I very much doubt that outside the peaks 315 passengers will have got on at Cheltenham, Gloucester, Stonehouse and Stroud, forcing Kemble passengers to stand. A two-car dmu suffices at such times between the HSTs at the moment...

If neither of you minds footing the fuel bills to cover the cost of carting air around in strings of empty coaches off-peak past Oxford and Swindon through hefty increases in your fares, then no, it doesn't matter at all that long formations are empty much of the time.

But as I noted above, it was done on the Cotswold Line in 2009 with HSTs and bled money from FGW's accounts, because the costs are far from trivial. If you are going to offer hourly off-peak services between London and Worcester and Cheltenham, then you are not going to be doing it with eight or nine-car sets.

 

[Rhydgaled]

I repeat, I have never said, in this thread or a couple of others, that there will be alternative formations, just that there could be and that the DfT has set out how this could potentially happen, should an operator want to ask for it.

Could be, not will be - there is a difference.

Exactly, could be, not will be. And until it will be, I will continue to be concerned that the bi-modes DaFT is ordering for GW could well only be 5-car.

If current growth rates in passenger traffic are maintained, the extra capacity a five-car IEP offers over a 180 may already be used up by the time IEP appears

How well do 180s cope at the moment, is their capacity already used up?

This pretence that intercity services only need to be full strength during the weekday is what is causing all the issues. All intercity services need to be full strength at all times. Enough with this 2 x 5 car rubbish.

Who said it would be reduced to five coaches? At busy times, seven days a week, a 2x5-car formation will be used throughout, same as HSTs work Saturday morning into London and back in the late afternoon and early evening now and go out to Hereford and Cheltenham on Sunday to work afternoon and early evening trains back to London. At other times of the weekend, FGW splits and joins Turbo formations at Oxford to balance loadings and seating capacity to the east and west.

At quieter times of the day, when trains split and join at Swindon, the Swindon passengers will have a 315-seat five-car train of their very own to board and I very much doubt that outside the peaks 315 passengers will have got on at Cheltenham, Gloucester, Stonehouse and Stroud, forcing Kemble passengers to stand. A two-car dmu suffices at such times between the HSTs at the moment...

If neither of you minds footing the fuel bills to cover the cost of carting air around in strings of empty coaches off-peak past Oxford and Swindon through hefty increases in your fares, then no, it doesn't matter at all that long formations are empty much of the time.

But as I noted above, it was done on the Cotswold Line in 2009 with HSTs and bled money from FGW's accounts, because the costs are far from trivial. If you are going to offer hourly off-peak services between London and Worcester and Cheltenham, then you are not going to be doing it with eight or nine-car sets.

Trains splitting at Swindon as well as Oxford, will there be enough sets? Aren't the Paddington - Cheltenham services all IC125s at present?

 

[Class172]

But as I noted above, it was done on the Cotswold Line in 2009 with HSTs and bled money from FGW's accounts, because the costs are far from trivial. If you are going to offer hourly off-peak services between London and Worcester and Cheltenham, then you are not going to be doing it with eight or nine-car sets.

What though if by the time IEP comes around, then passenger numbers have increased sufficiently to warrant an HST more of the time.

 

[Dave1987]

I'm confused as to where these sets are going to go when they are split off at Swindon? They can't just sit in the platform for an hour. And if you are not going to split them why not just have a fixed 10 car set and save the wasted middle cab space.

 

[LNW-GW Joint]

I'm confused as to where these sets are going to go when they are split off at Swindon? They can't just sit in the platform for an hour. And if you are not going to split them why not just have a fixed 10 car set and save the wasted middle cab space.

At Shrewsbury, every two hours, a 158 unit is tacked on to a Holyhead-Birmingham unit to make a 4-car set.
Having run to Birmingham International and back it detaches at Shrewsbury and gets attached to the next up train 10 minutes later. Good use of stock.
That's how it might work at Oxford/Worcester or Swindon with IEP (but with 5-car sets). The unit dropped off doesn't have to go anywhere except back to Padd on another service.
Fuel cost is one thing, but leasing cost will be the main driver.

 

[transmanche]

At Shrewsbury, every two hours, a 158 unit is tacked on to a Holyhead-Birmingham unit to make a 4-car set.
Having run to Birmingham International and back it detaches at Shrewsbury and gets attached to the next up train 10 minutes later. Good use of stock.
That's how it might work at Oxford/Worcester or Swindon with IEP (but with 5-car sets). The unit dropped off doesn't have to go anywhere except back to Padd on another service.

I think the same happens on King's Cross-Kings Lynn services. A unit is dropped off at Cambridge at about xx35 and sits there waiting for the next up service from Kings Lynn to be attached at about xx44. That must save two(?) units.

 

[tbtc]

All intercity services need to be full strength at all times

No they don't

 

[Dave1987]

No they don't

Passengers loading on all intercity services are high even during the off peak. And with passenger loadings growing fast it would be mad to make in intercity set not a fixed formation 8/9/10 car. Like when you couple 2 voyagers together the middle cabs is a big waste of space but on there own they aren't big enough.

 

[The Ham]

Passengers loading on all intercity services are high even during the off peak. And with passenger loadings growing fast it would be mad to make in intercity set not a fixed formation 8/9/10 car. Like when you couple 2 voyagers together the middle cabs is a big waste of space but on there own they aren't big enough.

IEP was being proposed in 2 lengths a 9 coach train and a 5 coach train, however the seating capacity is shown on the draft layouts is virtiulaly the same for a 9 coach train and two 5 coach trains (with a 5 coach train having about 10% more capacity than the current class 180's).

Therefore even if the line was able to produce enough passengers to justify full 9 coach trains all the time there wouldn't be any capcity reason to do so. Yes there would be other reasons to do so, but then there are reasons not to (such as a fault only shortening the trian rather than it not turning up).

 

[HSTEd]

While one fault would not cause the entire train to fail to turn up, there would be double the number of single-points-of-failure to fail which would mean that there would be twice as many failures on average.

So are ~2 half length services cheaper than one cancelled one?
Additionally you have to include the increased staffing costs with split sets.

I am of the opinion that, on many routes, it is better to go for max train length all the time and simply dump huge numbers of very cheap advance tickets onto the market to try and fill the off peak services.

 

[Class172]

If they really wanted to, they could make the advances cheap enough so that it offers a viable route for passengers from Birmingham to London (obviously it is slower) as it could attract people onto the Cotswold line.

 

[anthony263]

If they really wanted to, they could make the advances cheap enough so that it offers a viable route for passengers from Birmingham to London (obviously it is slower) as it could attract people onto the Cotswold line.

They could also offer advance tickets on the Cotswold Lines services especially say from Hereford to Oxford and London.

I can see FGW perhaps doing something similar if they run a Milton Keynes - Oxford - Reading - London Paddington service when the electrified east-west line is opened.

 

[jimm]

Exactly, could be, not will be. And until it will be, I will continue to be concerned that the bi-modes DaFT is ordering for GW could well only be 5-car.

How well do 180s cope at the moment, is their capacity already used up?

Trains splitting at Swindon as well as Oxford, will there be enough sets? Aren't the Paddington - Cheltenham services all IC125s at present?

As I have said previously FGW managers have spoken in public about the question of whether five-car sets will cope, based on loadings on some 180 services and growing custom, which is a factor in the issue getting into the GW invitation to tender. They are the people who are running GW services now, know what the growth trends look like and certainly do not want a repeat of the XC Voyager fiasco - not that the IEP plan suggests a universal fleet of short trains which never couple to anything anyway. Give them a chance - until the franchise issue is out of the way, things like this can't be addressed.

How else do you think they are going to provide an hourly London service for Cheltenham without splitting? You obviously haven't looked at the current timetable from your comment about HSTs, they only run every two hours outside the peaks - and they are very quiet past Swindon, same as the off-peak Hereford HSTs are past Oxford.

What though if by the time IEP comes around, then passenger numbers have increased sufficiently to warrant an HST more of the time.

They may increase - hence my frequent comments about FGW raising the question over five-car formations - but they sure as hell won't increase enough past Oxford or Swindon to justify use of a 600-plus seat train off-peak.

I'm confused as to where these sets are going to go when they are split off at Swindon? They can't just sit in the platform for an hour. And if you are not going to split them why not just have a fixed 10 car set and save the wasted middle cab space.

How about straight back to London with a set that is coming into Swindon from Cheltenham.

Passengers loading on all intercity services are high even during the off peak. And with passenger loadings growing fast it would be mad to make in intercity set not a fixed formation 8/9/10 car. Like when you couple 2 voyagers together the middle cabs is a big waste of space but on there own they aren't big enough.

Ride on the 08.22 and 10.22 from Paddington to Hereford west of Oxford and then tell me passenger loadings on all intercity services are high even during the off-peak - you won't be able to. But the 15.13 most certainly is on its way back to London - east of Oxford, from where it forms the 17.31 express service to Paddington. That's where the flexibility would come in handy.

While one fault would not cause the entire train to fail to turn up, there would be double the number of single-points-of-failure to fail which would mean that there would be twice as many failures on average.

So are ~2 half length services cheaper than one cancelled one?
Additionally you have to include the increased staffing costs with split sets.

I am of the opinion that, on many routes, it is better to go for max train length all the time and simply dump huge numbers of very cheap advance tickets onto the market to try and fill the off peak services.

They could also offer advance tickets on the Cotswold Lines services especially say from Hereford to Oxford and London.

I can see FGW perhaps doing something similar if they run a Milton Keynes - Oxford - Reading - London Paddington service when the electrified east-west line is opened.

Lose one set out of two and you can still run a service of some sort. Lose one big train and there's no service.

And when you have filled your large train with lots of cheap tickets from west of Oxford or Swindon - which you won't be able to do, given the rather modest populations of the places served - how do you propose to accommodate the large numbers of people wanting to travel between Oxford or Swindon and Reading and London, for whom one of the sets in a paired formation is intended? We've had this discussion elsewhere only recently - the 222s for GW thread? - and I don't recall anyone answering this question when I posted it there.

Even if East-West route trains are grafted on to the London-Oxford semi-fast service past 2019, no-one will ever use it as a way to get from London to anywhere on that line given the range of far faster options that already exist or, in the case of Winslow, will exist.

If they really wanted to, they could make the advances cheap enough so that it offers a viable route for passengers from Birmingham to London (obviously it is slower) as it could attract people onto the Cotswold line.

:roll:

 

[Mintona]

I dispute the fact that off peak trains are quiet west of Swindon. As I said yesterday, the HST I was on was full and standing from Kemble. The population of Gloucester and Cheltenham together is roughly the same as Swansea, will they be splitting 2 5 cars at Cardiff for the journey west to Swansea as well?

 

[Rhydgaled]

Give them a chance - until the franchise issue is out of the way, things like this can't be addressed.

One of my worries is that, by the time the franchise issues are resolved, it'll be well past Hitachi's 'design freeze' and the sets will be fixed at DaFT's formations and it'll be too late for the new TOC to have their input.

You obviously haven't looked at the current timetable from your comment about HSTs, they only run every two hours outside the peaks - and they are very quiet past Swindon, same as the off-peak Hereford HSTs are past Oxford.

I didn't say they were hourly IC125s now, I just asked to confirm my assumption that the current Paddington - Cheltenham services are IC125s. The fact they are less frequent now doesn't really change the point I was trying to make. You said that FirstGW tried running the Paddington-Hereford route with IC125s but found they weren't filling up enough so brought in 166s/165s, and then brought back some 180s. Ok, maybe that shows the Cotswolds trains don't always need to be long west of Oxford but they didn't bring back 180s for Cheltenham services, which suggests that maybe the IC125s are needed all the time on that route. Just because the frequency to London will be increased, doesn't mean the current trains will get alot quieter. There'll be some spreading out of loadings, but also the more frequent service would attract more passengers.

 

[HSTEd]

Lose one set out of two and you can still run a service of some sort. Lose one big train and there's no service.

You would potentailly be looking at 150% overloading if that happens at Rush hour... meaning you will leave people behind, which muddies the waters considerably when it comes to the choice between two short formed trains and one cancelled one.

And when you have filled your large train with lots of cheap tickets from west of Oxford or Swindon - which you won't be able to do, given the rather modest populations of the places served - how do you propose to accommodate the large numbers of people wanting to travel between Oxford or Swindon and Reading and London, for whom one of the sets in a paired formation is intended?

Presumably you wouldn't sell so many advanced purchase tickets that train would be overloaded at the Oxford/London end.
In return for the fairly minor additional rolling stock costs and even more minor additional fuel costs you avoid numerous operational headaches and you also end up with a more uniform overall fleet consisting of a small number of different formation sizes.

London-Oxford is approximately 1hr.
Oxford-Great Malven is 1hr36.

Assuming No split and an hourly service to Great Malvern (I believe that is the normal end point for cotswold services in the IEP specification) that would require six 9-car sets, for a total of 54 carriages and six traincrew slots.

If we have a split, we will need 3 sets on the London-Oxford section (because of recovery times and the like meaning we will just miss the ~2hr cycle time window) and a further six sets on the Great Malvern section.
9 sets for a total of 45 carriages and nine traincrew slots.

So by performing this split you have saved nine carriages and added three additional traincrew slots to your crew requirement.
The savings are not really that large.

EDIT:

And I imagine the motor vehicles are more expensive than the trailers, and a 9-car formation has five engines instead of six, as well as only having two cabs instead of four.

 

[Rhydgaled]

will they be splitting 2 5 cars at Cardiff for the journey west to Swansea as well?

It was feared that this was the plan back when Swansea wasn't included in the electrification programme and the fleet had 5-car 'electrics' as well as 5-car bi-modes. The idea was the electric would stop at Cardiff and the bi-mode carry on to Swansea. The result would have been tragic.

 

[JamesRowden]

While one fault would not cause the entire train to fail to turn up, there would be double the number of single-points-of-failure to fail which would mean that there would be twice as many failures on average.

I do not think that your assumption that a 9-car set has exactly the same probability of faliure as a 5-car set can be validated unless you have some data............

 

[jimm]

I dispute the fact that off peak trains are quiet west of Swindon. As I said yesterday, the HST I was on was full and standing from Kemble. The population of Gloucester and Cheltenham together is roughly the same as Swansea, will they be splitting 2 5 cars at Cardiff for the journey west to Swansea as well?

Try reading my posts more carefully - I was very clear about the formations you could expect to see on a Saturday morning and other busy times of the weekend - full-length.

If you want to define off-peak as anything outside the Monday to Friday morning and evening peak periods, that's up to you, but there are clearly peak and off-peak periods at weekends as well, aren't there? Which was what I was trying to point out. You only have to look at the volume of traffic on Sunday afternoons and early evenings to see that - but you most certainly do not need 600 seats beyond Oxford and Swindon in the middle of the day on a Saturday or a weekday, nor a Sunday morning.

One of my worries is that, by the time the franchise issues are resolved, it'll be well past Hitachi's 'design freeze' and the sets will be fixed at DaFT's formations and it'll be too late for the new TOC to have their input.

I didn't say they were hourly IC125s now, I just asked to confirm my assumption that the current Paddington - Cheltenham services are IC125s. The fact they are less frequent now doesn't really change the point I was trying to make. You said that FirstGW tried running the Paddington-Hereford route with IC125s but found they weren't filling up enough so brought in 166s/165s, and then brought back some 180s. Ok, maybe that shows the Cotswolds trains don't always need to be long west of Oxford but they didn't bring back 180s for Cheltenham services, which suggests that maybe the IC125s are needed all the time on that route. Just because the frequency to London will be increased, doesn't mean the current trains will get alot quieter. There'll be some spreading out of loadings, but also the more frequent service would attract more passengers.

Series production isn't starting until 2016, so of course there is still time - it's nothing to do with 'design' - the trains are set up to be configured in all sorts of lengths if required, same as the 22xs can be now.

I am talking about the intermediate franchise period. Not the post-2016 one. If FGW get three more years, they will be dealing with Hitachi on preparations for IEP introduction and the shape of the fleet - FGW are having to put together a 'bid' for DfT. It's not just a 'steady as you go' contract to tide things over - with all the things going on along the GWML in the next few years, it can't be.

So you hadn't looked at the timetable, which would have confirmed your assumption.

What the Cheltenham service shows is that FGW has only has five 180s - just enough to handle the Cotswold off-peak and contra-peak diagrams, so they can't use them to Cheltenham as well - where they most certainly would go if there were still all 14 sets with FGW.

Go to Cheltenham and get on an off-peak HST there and go to Swindon and once you've done that, then you will know whether a train with 500 or 580 seats is needed west of Swindon, or whether 300 would be a more reasonable capacity. A more frequent service will not attract so many more passengers as to get anywhere near filling a long train every hour. The connections from Swindon between the HSTs are 15x dmus, which don't even carry 200.

The populations of Stroud, Gloucester, Cheltenham, and Worcester and Hereford (not the biggest towns and cities in England to start with) - are not all frantically travelling up and down to London all the time, so even if there is growth, which seems a reasonable assumption, it will not be so great as to require 600-seat trains off-peak.

You would potentailly be looking at 150% overloading if that happens at Rush hour... meaning you will leave people behind, which muddies the waters considerably when it comes to the choice between two short formed trains and one cancelled one.

Presumably you wouldn't sell so many advanced purchase tickets that train would be overloaded at the Oxford/London end.
In return for the fairly minor additional rolling stock costs and even more minor additional fuel costs you avoid numerous operational headaches and you also end up with a more uniform overall fleet consisting of a small number of different formation sizes.

London-Oxford is approximately 1hr.
Oxford-Great Malven is 1hr36.

Assuming No split and an hourly service to Great Malvern (I believe that is the normal end point for cotswold services in the IEP specification) that would require six 9-car sets, for a total of 54 carriages and six traincrew slots.

If we have a split, we will need 3 sets on the London-Oxford section (because of recovery times and the like meaning we will just miss the ~2hr cycle time window) and a further six sets on the Great Malvern section.
9 sets for a total of 45 carriages and nine traincrew slots.

So by performing this split you have saved nine carriages and added three additional traincrew slots to your crew requirement.
The savings are not really that large.

EDIT:

And I imagine the motor vehicles are more expensive than the trailers, and a 9-car formation has five engines instead of six, as well as only having two cabs instead of four.

And what do you think happens now in the peak when one train out of a paired formation - on FGW and elsewhere - fails? There's overcrowding. Or you cancel a Cotswold Line peak HST out of Paddington now? There's overcrowding on anything going towards Oxford, or the Turbo or 180 that gets sent instead. None of that will change whether it's IEP or any other train.

No, you certainly wouldn't sell so many advances as to overload the train at the Oxford/London end but then you would still have a very empty train west of Oxford, because of the numbers you would have to allow for travelling between Oxford, Reading and London. Never mind that not everyone wants an advance in the first place - someone will know the figure I'm sure, but it's something like six to eight per cent of journeys. Many people value having a flexible ticket.

Your stuff about stock seems to be based on the assumption that the IEP will continue to trundle up and down at Turbo timings. The specification for IEP clearly states it should be able to run London to Hereford well inside three hours, making all the current regular stops on the way.

 

[HSTEd]

And what do you think happens now in the peak when one train out of a paired formation - on FGW and elsewhere - fails? There's overcrowding. Or you cancel a Cotswold Line peak HST out of Paddington now? There's overcrowding on anything going towards Oxford, or the Turbo or 180 that gets sent instead. None of that will change whether it's IEP or any other train.

So the effect of a cancelled 9-car or of 2 short formed 5-car trains is comparable? Its just a matter of if the overcrowding is concentrated onto a smaller number of trains or spread out of more services.
This doesn't really help your argument of "a failure will only take out half the set".

No, you certainly wouldn't sell so many advances as to overload the train at the Oxford/London end but then you would still have a very empty train west of Oxford, because of the numbers you would have to allow for travelling between Oxford, Reading and London. Never mind that not everyone wants an advance in the first place - someone will know the figure I'm sure, but it's something like six to eight per cent of journeys. Many people value having a flexible ticket.

Running half-empty trains around if they simplify operations is surprisingly cheap, fuel costs are not a really large fraction of the cost of operating train services these days.

This is why there was never really meant to be significant doubled up running of Voyagers/Meridians when they first arrived, such things have only really occured relatively recently (on a large scale) to deal with the operational problems in the aftermath of Operation Princess and the reassignment of the Hull Trains sets to MML.

Your stuff about stock seems to be based on the assumption that the IEP will continue to trundle up and down at Turbo timings. The specification for IEP clearly states it should be able to run London to Hereford well inside three hours, making all the current regular stops on the way.

Since the journey time improvements are likely to disproportionately favour the route section between Hereford and Oxford, it would tend to further reduce the advantage of splitting the trains in the middle since it would reduce the excess stock requirement of running all trains through.
Additionally it is only a few minutes of saving so it shouldn't reflect on diagramming too harshly.

I do not think that your assumption that a 9-car set has exactly the same probability of faliure as a 5-car set can be validated unless you have some data............

Well if you look at the kinds of failures that will cause a train to be failed rather than sent out regardless, they tend to be things like cab radios, windscreens... things like that. Things which scale by the number of cabs (or the number of formations running in service) rather than the number of vehicles in service.

If the air con goes out on a carriage in a set or one of the engines on a bi-mode set goes out you can probably send the train out regardless and bring it back in for servicing at the earliest practical opportunity.

 

[TheWalrus]

I think half the problem regarding Cheltenham and Great Malvern services being lightly loaded is poor infrastructure. It'd be quicker to drive from Cheltenham to Swindon than to catch the train, which isn't much of an incentive to take the train. On the Cotswolds line although there are higher line speeds of 100mph in places, a lot of it is slow for Intercity services and also due to the single track, waiting around at Evesham for a few minutes adds on more time which makes the train less attractive. So I believe infrastructure is our problem affecting demand on these two routes.

 

[Rhydgaled]

What the Cheltenham service shows is that FGW has only has five 180s - just enough to handle the Cotswold off-peak and contra-peak diagrams, so they can't use them to Cheltenham as well - where they most certainly would go if there were still all 14 sets with FGW.

But you said that 166s/165s were used on the Cotswolds, due to IC125s being an over-provision of capacity, when FirstGW had no 180s at all. If running IC125s to Cheltenham off-peak was hurting, wouldn't they have left the 165s/166s on the Cotswolds and put the five returning 180s on Cheltenham runs off-peak?

Go to Cheltenham and get on an off-peak HST there and go to Swindon and once you've done that, then you will know whether a train with 500 or 580 seats is needed west of Swindon, or whether 300 would be a more reasonable capacity.

...

The populations of Stroud, Gloucester, Cheltenham, and Worcester and Hereford (not the biggest towns and cities in England to start with) - are not all frantically travelling up and down to London all the time, so even if there is growth, which seems a reasonable assumption, it will not be so great as to require 600-seat trains off-peak.

Ok, what if they need over 300 but less than 600 seats off-peak? Same for the Cotswolds, and one of the reasons why I've suggested 7-car bi-modes in the past. That provides a more reasonable capacity for the beyond-the-wires destinations, but there is the issue of having alot of passengers wanting to board at places like Reading and Swindon, so maybe you need 9-car to make sure there's room left for them.

 

[JamesRowden]

Well if you look at the kinds of failures that will cause a train to be failed rather than sent out regardless, they tend to be things like cab radios, windscreens... things like that. Things which scale by the number of cabs (or the number of formations running in service) rather than the number of vehicles in service.

Could some of those problems be nullified when running 2X5 formations by switching the order of the 5-car sets within the formation?