IEP for beginners

[HSTEd]

You'd need something to replace them on CrossCountry first. Perhaps I might suggest some kind of "bi-modal" train?

I meant at CrossCountry.

I assume XC will get orders for bi-modes as when the Voyager fleet nears retirement.
Isn't it still tied to ICXC by the original agreement though?

 

[jimm]

I have answered your point jimm or have you not bothered to read it?:roll:

You mean this?

They will only need an exam once a month probably less considering how little miles they will be hauling over.

I then pointed out, in post No 480, that your claim of "how little miles" they would be doing was pretty baseless, but you ignored that. The mileages involved are not trivial - A round trip Oxford-Hereford is over 170 miles. Once a month to a depot?

And you still haven't said how you're going to fuel them/carry out basic exams at places without and facilities.

 

[AlanFry1]

To be honest while IEP could turn out to be a good train, the whole project has been managed badly and with too much buracratic complexity

They have also need to order a lot less bi-mode/diesel versions in favour of more electrification

 

[Dave1987]

You mean this?



I then pointed out, in post No 480, that your claim of "how little miles" they would be doing was pretty baseless, but you ignored that. The mileages involved are not trivial - A round trip Oxford-Hereford is over 170 miles. Once a month to a depot?

And you still haven't said how you're going to fuel them/carry out basic exams at places without and facilities.

Look having a diesel loco travel to the depot under the wires once a month for an a exam is far far less wasteful that dragging bi-mode diesels under the wires constantly. You have not addressed my point that bi-mode is wasting energy constantly. We have already discussed that it will cost about £80,000 ish in energy per train per year just to cart around the underfloor engines under the wires. That is far far more wasteful that a diesel travelling to the depot once a month.

 

[tbtc]

SCR will probably help with the emissions issues.

And as to the electrification issue.

We will never see the resources neccesary to achieve total electrification without purchase of bi mode units for intercity work and if the bi mode units are ordered the justification for electrification of the extremities of the intercity network dissapears.

Bi-mode IEP will kill the electrification programme essentially.
(Since the electrification of the extremities of the network is best justified as eliminating under-wires diesel running).

I disagree - it'll always be cheaper to have electrification than diesels - bi-more just allows us to progressively extend the wiring without it impacting upon service levels/ traction.

For example, Edinburgh to Aberdeen will be wired in the next fifty years. Bi-mode allows the "switchover" point to gradually move further up the line until that day.

Look having a diesel loco travel to the depot under the wires once a month for an a exam is far far less wasteful that dragging bi-mode diesels under the wires constantly. You have not addressed my point that bi-mode is wasting energy constantly. We have already discussed that it will cost about £80,000 ish in energy per train per year just to cart around the underfloor engines under the wires. That is far far more wasteful that a diesel travelling to the depot once a month.

Is it more or less wasteful than dragging a full eleven coach Pendolino all the way from Oxford to Worcester or Hereford each hour (instead of splitting off a five coach IEP to run most services beyond Oxford)?

 

[AndyLandy]

Look having a diesel loco travel to the depot under the wires once a month for an a exam is far far less wasteful that dragging bi-mode diesels under the wires constantly. You have not addressed my point that bi-mode is wasting energy constantly. We have already discussed that it will cost about £80,000 ish in energy per train per year just to cart around the underfloor engines under the wires. That is far far more wasteful that a diesel travelling to the depot once a month.

Round and round in circles we go! Didn't tbtc already point out that it's the equivalent of a single passenger fare per service? That's hardly a big deal. Also, does anyone actually give a hoot about inefficiencies on electricity? It's cheap for us to produce and it's (allegedly) much more environmentally friendly. Wasting a bunch of energy under-the-wires instead of burning diesel is certainly far more politically acceptable.

 

[RAGNARØKR]

I disagree - it'll always be cheaper to have electrification than diesels - bi-more just allows us to progressively extend the wiring without it impacting upon service levels/ traction.

For example, Edinburgh to Aberdeen will be wired in the next fifty years. Bi-mode allows the "switchover" point to gradually move further up the line until that day.

More likely is that it will kill the possibility that Aberdeen will be electrified before the IEP is due for scrap.

Is it more or less wasteful than dragging a full eleven coach Pendolino all the way from Oxford to Worcester or Hereford each hour (instead of splitting off a five coach IEP to run most services beyond Oxford)?

Or dragging five unpowered vehicles - a 200 ton load - beyond Oxford?

If they are really that stretched they could ask the nice people at the Great Western Society at Didcot to supply the traction. And a restaurant car like the one in the picture, don't you think people would like that?

Seriously though, it would not be much of stretch for a medium sized diesel loco geared for the job.
--- old post above --- --- new post below ---

I meant at CrossCountry.

I assume XC will get orders for bi-modes as when the Voyager fleet nears retirement.
Isn't it still tied to ICXC by the original agreement though?

When is that likely to happen? As hauled vehicles they would be good for the next half century.

 

[Dave1987]

Round and round in circles we go! Didn't tbtc already point out that it's the equivalent of a single passenger fare per service? That's hardly a big deal. Also, does anyone actually give a hoot about inefficiencies on electricity? It's cheap for us to produce and it's (allegedly) much more environmentally friendly. Wasting a bunch of energy under-the-wires instead of burning diesel is certainly far more politically acceptable.

Well if the anti nuclear mob has its way then electric wont be green at all as NIMBYs are against wind farms. The point is is there is a solution where you don't need to waste any energy under the wires (depending on where the maintenance facilities for the locos are) that is also cheaper.

 

[HSTEd]

When is that likely to happen? As hauled vehicles they would be good for the next half century.

The engine blocks are integral to the structure of the vehicles.
You can't remove them without fatally weakening the entire vehicle.
THerefore you will be carrying giant lumps of metal around under these hauled vehicles forever.

And hauled vehicles are not something we need, multiple unit operation is the future of Passenger Rail outside of some very specific niches.
--- old post above --- --- new post below ---

Well if the anti nuclear mob has its way then electric wont be green at all as NIMBYs are against wind farms. The point is is there is a solution where you don't need to waste any energy under the wires (depending on where the maintenance facilities for the locos are) that is also cheaper.

The anti nuclear mob will lose when we hit the sorts of prices that are going tobe required to support off shore wind en masse.
We will just have to be ready to take advantage of the infighting that will destroy the "enviromentalist" movement at that time.

And I can't see how building a brand new fleet of locomotives that will sit idle for most of there operational life waiting for a handful of journeys, from scattered posistions across the network would be cheaper than just accepting a tiny additional cost to haul the diesel engines around all the time.

And as to the exhaust pressure causing huge reductions in engine efficiency, this has been shown not to be a showstopper thanks to advances in Selective Catalytic Reduction technology, indeed the emissions compliant variation of the Cl172s engine has comparable efficiency to the one actually used in said trains.
(We aren't experiencing a huge decrease in lorry engine efficiency are we? And they are using engines in this power range)

 

[Dave1987]

The engine blocks are integral to the structure of the vehicles.
You can't remove them without fatally weakening the entire vehicle.
THerefore you will be carrying giant lumps of metal around under these hauled vehicles forever.

And hauled vehicles are not something we need, multiple unit operation is the future of Passenger Rail outside of some very specific niches.
--- old post above --- --- new post below ---


The anti nuclear mob will lose when we hit the sorts of prices that are going tobe required to support off shore wind en masse.
We will just have to be ready to take advantage of the infighting that will destroy the "enviromentalist" movement at that time.

And I can't see how building a brand new fleet of locomotives that will sit idle for most of there operational life waiting for a handful of journeys, from scattered posistions across the network would be cheaper than just accepting a tiny additional cost to haul the diesel engines around all the time.

And as to the exhaust pressure causing huge reductions in engine efficiency, this has been shown not to be a showstopper thanks to advances in Selective Catalytic Reduction technology, indeed the emissions compliant variation of the Cl172s engine has comparable efficiency to the one actually used in said trains.
(We aren't experiencing a huge decrease in lorry engine efficiency are we? And they are using engines in this power range)

I'm sorry but this doesn't say anything about the fact it is far far easier to comply with emmisions regs on a loco than it is with underfloor engines. These new loco's bing designed and built now will be far more efficicient than any modern dmu. I know someone who works in LM's planning dept and thy have said that the 172's are an improvement on the 150's in terms of acceleration but their fuel efficiency is rubbish. Why spend shed loads of money on something that is inefficient, wasteful on electric, and when the wires go up fully your gonna have loads of useless underfloor Diesel engines.

 

[HSTEd]

I'm sorry but this doesn't say anything about the fact it is far far easier to comply with emmisions regs on a loco than it is with underfloor engines. These new loco's bing designed and built now will be far more efficicient than any modern dmu. I know someone who works in LM's planning dept and thy have said that the 172's are an improvement on the 150's in terms of acceleration but their fuel efficiency is rubbish.

That might have something to do with the CLass 172 weighing in at north of 90 tonnes, compared to the relatively lightweight 72 tonnes of the Class 150.
I happen to know that the power plant in the Class 172 is actually 10% more efficient in terms of horsepower-hours per litre of diesel than the Cummins plant used in the Class 150s. (I looked up the specs)

Its just any fuel efficiency gains have been washed out by the drastically increased weight of the unit and by the increases in hotel loads.

Why spend shed loads of money on something that is inefficient, wasteful on electric, and when the wires go up fully your gonna have loads of useless underfloor Diesel engines.

Why spend shed loads of money on something that is inefficient and wasteful on diesel, and when the wires go up fully your gonna have loads of useless diesel locomotives?

There is nowhere for these high power high speed diesel locomotives to go afterwards.
There is no traffic that might need them. (And before you go on about "Mixed Working".... mixed working is dead and has been for some time).

IEP underfloor engines however might have a future in a new build of electric IEPs later on as the recovery engines or in future Class 20 replacements on RHTT and similar trains where Class 66s are hopelessly overpowered.

 

[Dave1987]

That might have something to do with the CLass 172 weighing in at north of 90 tonnes, compared to the relatively lightweight 72 tonnes of the Class 150.
I happen to know that the power plant in the Class 172 is actually 10% more efficient in terms of horsepower-hours per litre of diesel than the Cummins plant used in the Class 150s. (I looked up the specs)

Its just any fuel efficiency gains have been washed out by the drastically increased weight of the unit and by the increases in hotel loads.



Why spend shed loads of money on something that is inefficient and wasteful on diesel, and when the wires go up fully your gonna have loads of useless diesel locomotives?

There is nowhere for these high power high speed diesel locomotives to go afterwards.
There is no traffic that might need them. (And before you go on about "Mixed Working".... mixed working is dead and has been for some time).

IEP underfloor engines however might have a future in a new build of electric IEPs later on as the recovery engines or in future Class 20 replacements on RHTT and similar trains where Class 66s are hopelessly overpowered.

Sorry but that is complete rubbish!! The new class 68 are going to be suitable for both passenger and freight use. That is complete clap trap that the locos would have no use once the wires are fully up. You could not just shove underfloor engines into a class 20 replacement. The engines would have to be designed to be retrofitted.

 

[tbtc]

there is a solution where you don't need to waste any energy under the wires

Is this the solution that wastes a little energy in having a loco dragging eleven coach Pendolini all the way from Oxford to Hereford?

(rather than a five coach IEP making the journey itself)

 

[AndyLandy]

Is this the solution that wastes a little energy in having a loco dragging eleven coach Pendolini all the way from Oxford to Hereford?

(rather than a five coach IEP making the journey itself)

Playing Devil's advocate here, to be fair, there's no reason why you couldn't have a 2x5 car EMU set split at Oxford and for only the front half to be dragged by a loco.

That doesn't solve the other issues, but it would solve that particular one.

 

[tbtc]

Playing Devil's advocate here, to be fair, there's no reason why you couldn't have a 2x5 car EMU set split at Oxford and for only the front half to be dragged by a loco.

That doesn't solve the other issues, but it would solve that particular one.

You are right. But as Dave1987 suggested 390s as his "solution", I'm trying to show that there are flaws with every plan (including with bi-mode).

The difference is that those in favour of bi-mode seem to be aware of the problems with this "least bad" solution. Those in favour of other things don't seem to notice the flaws that their own plans have.

 

[Zoe]

That is complete clap trap that the locos would have no use once the wires are fully up.

Is there suddenly going to be a demand for extra diesel freight locomotives at the same time the IEP routes are fully electrified?

 

[HSTEd]

Sorry but that is complete rubbish!! The new class 68 are going to be suitable for both passenger and freight use.

Find me a freight use that a 3750hp 100mph capable bo-bo locomotive with the medium speed diesels the eurolight has would be better at than something like a Class 66 or a Class 70?
The needs of freight and passenger locomotives have just diverged too much.

That is complete clap trap that the locos would have no use once the wires are fully up. You could not just shove underfloor engines into a class 20 replacement. The engines would have to be designed to be retrofitted.

Actually you can do so, you cannot go the other way but it is very easy to put an underfloor engine into a Class 20 replacement, since it will definitely fit inside the body of the locomotive.

But the likelyhood is that most of the bi-mode power plants will end up in electric IEPs of later tranches in the future as the recovery power unit.

 

[The Ham]

You seem to be the best number-cruncher out there in this discussion group. With your skill (and patience), can you apply this to capital costs, as these are reflected in lease charges? You can make a few assumptions eg that the mark 3 fleet is retained and refurbished at say, £400k per vehicle, that there is some new build of hauled vehicles on top eg to provide driving trailers and DDA compliant vehicles, at say, £1.2 million per vehicle, and that traction is by electric and diesel locomotives at the going rate which seems to be about £3 million a unit. Assume a future life for the mark 3 stock on the basis that it will have to be replaced over the ten year period 2035 to 2045.

Put this together with the track access charges and fuel costs which you have carefully put together, and then a coherent picture will be visible.

There are a lot of variables that need to be thought about. For instance do I compare your suggestion against the length of time the the IEP's are programmed to run for (i.e. 27.5 years from 2017) in which case I would need to cost a whole new fleet of coaches just at the end of that time period?

What about if the period in question goes over the life span of the locos and they need replacing again?

How many locos do I provide, just enough of the number of services, enough for the number of services plus 10% for maintenance or enough for the services and maintenance and a miss match in the type of loco (i.e. do we need a few because there will be some which are not able to be fully utilised all the time and/or so services can run to different destinations)?

Are all the mark 3's able to be refitted and used for another 30 years or do we need to replace them on a rolling program, in which case do we bother to refit them all or just those that will last more than a few years?

Do I only replace the existing coaches or do we add new capacity to make the new stock of a comparable capacity to the IEP's?

Do I assume that (if we are lengthening trains to meet capacity) that these trains can fit within existing stations lengths or are you going to provide a list of all the stations which have more than a million passengers a year and their platform lengths so that a view can be taken as to which ones need lengthening? Alternatively do we just assume that every station (including stations where a lot of people change such as Reading) just rely on SDO?

Do I assume that we are only running one loco per train, or do we need two (like the existing HST's) to maintain and/or improve on the existing acceleration or do we accept a slowing of journey times?

If we accept slower journeys, how many extra trains would be needed to maintain the existing timetable frequencies in which case a recast of the timetable may well be required.

What assumptions do I make for track access charges, are the new carriages the same as the existing mark 3's or do we "upgrade" them to the mark 4's or do they end up costing somewhere between the two.

Can we just build new mark 3's or do they need to be tested to meet current standards?

What do I assume are the costs of new depots (even if they are just your suggested mini depot for refuelling and hitting the loco's with a big hammer when they don't work)?

Are the above costs including maintenance during their life cycle, if not is this comparable to IEP's and if it differs what assumptions should be made.

Depending on the answers and assumptions it is likely that whoever undertook such a task would be able to bend the answers to meet their own view and so the answers would not be overly helpful in providing an answer that proves that IEP is good or bad.

For instance set the lifespan the same as IEP and as all the coaches would basicly be brand new at the end of the period you are looking at and the costs would be a lot higher than IEP, conversely extend it to 40 years and people then start to question why you are comparing life cycles of a different length.

Compare the cost per coach and IEP will always look a lot worse, whilst if you compare the cost per 100 seats and the costs appear to look much more favourable.

In short I have much more interesting things to do with my life than crunch a lot of numbers for which there is no right answer and regardless what answer I come out with will be slated by virtually everyone.

 

[jimm]

Playing Devil's advocate here, to be fair, there's no reason why you couldn't have a 2x5 car EMU set split at Oxford and for only the front half to be dragged by a loco.

That doesn't solve the other issues, but it would solve that particular one.

No it doesn't solve that particular one at all. As i have pointed out elsewhere, the peak loads west of Oxford and Swindon can fill HSTs now, so however any future train is powered, you will be sending long formations all the way.

Sorry but that is complete rubbish!! The new class 68 are going to be suitable for both passenger and freight use. That is complete clap trap that the locos would have no use once the wires are fully up. You could not just shove underfloor engines into a class 20 replacement. The engines would have to be designed to be retrofitted.

Yes, the new Class 68 will be suitable for both freight and passenger use - and will, as a result, have gearing that is a compromise between those two requirements, like the Class 47, which was displaced from heavy freight duties by purpose-built designs in the shape of 56s, 58s and 59s. The class 68 might do an okay job on duties like the Cotswold Line's start-stop cycle if required, like the HST does, but it will never, ever match the speed off the mark of a Class 180, nor the similar IEP bi-mode.

And, as I have noted previously, the Class 68's Caterpillar engine has never been put though that kind of duty cycle on a railway - it took a very long time until the VP185 and the big MAN diesels came along that something that could take the same punishment as a Valenta was available for the HSTs.

If wiring continues to spread, then the chances are the freight operators may look to make more use of electric locos - especially if the so-called 'last-mile' small diesel engines in new electric loco types on the Continent prove their worth for work in non-electrified sidings and terminals - or maybe they should be banned from our shores for wastefully carting around a diesel engine and fuel under the wires?

A move in this direction over here would mean a diminishing requirement for diesels in a country which currently has hundreds of pretty young heavy-haul diesels with lots of life left in them. Will a small number of much lighter engines (a 68 weighs in at just 85 tonnes v 129 tonnes for a 66 and a 70), which will have been put through punishing use on fast passenger work, actually be a very attractive proposition for freight use?

 

[RAGNARØKR]

In short I have much more interesting things to do with my life than crunch a lot of numbers for which there is no right answer and regardless what answer I come out with will be slated by virtually everyone.

Yes. Which sums up this whole debate very nicely.

Here we have a situation which the Southern has lived with since the 1930s - a network of which a substantial and growing proportion is electrified, but residues of non-electrified mileage remain. It is less than ideal to the point of being a nuisance but various solutions have been successfully adopted over the years, though never this one.

The decision to go for bi-mode has all the hallmarks of the kind of bright idea that the Civil Service Mind (CSM) would come up with - the train that can do everything. Opposition retreats in the face of someone's determination. The original simple concept then fragments into a collection of variants as the practicalities intrude.

If the idea of a CSM sounds ridiculous, bear in mind that it is a self-selecting, self-perpetuating oligarchy, with hand picked entrants. Those who fit proceed smoothly up the hierarchy. Those who do not fit go away disillusioned and apply their talents somewhere else.

None of the TOCs wants these trains. The ROSCOs were not interested in even getting involved. There was no support from the industry.

Enough said.

 

[Murph]

The decision to go for bi-mode has all the hallmarks of the kind of bright idea that the Civil Service Mind (CSM) would come up with - the train that can do everything. Opposition retreats in the face of someone's determination. The original simple concept then fragments into a collection of variants as the practicalities intrude.

It doesn't have to be a collection of variants, it can end up as a single frankentrain that doesn't particularly meet any of the original goals. It rather puts me in mind of http://en.wikipedia.org/wiki/The_Pentagon_Wars

More seriously though, I think personally the single biggest failing that I see is if we end up needlessly having a noisy vibrating diesel under a lot of passenger coaches. It's really going to be a horrible, painful, embarassing step into mediocrity if we lose the comfortable, smooth, silent ride quality of the HST sets in IC-diesel areas The idea of bi-mode is not a bad one, it just shouldn't be at the loss of quality of service.

 

[tbtc]

I think personally the single biggest failing that I see is if we end up needlessly having a noisy vibrating diesel under a lot of passenger coaches. It's really going to be a horrible, painful, embarassing step into mediocrity if we lose the comfortable, smooth, silent ride quality of the HST sets in IC-diesel areas The idea of bi-mode is not a bad one, it just shouldn't be at the loss of quality of service.

Maybe your hearing is better than mine, but I'm never bothered by underfloor engines - some enthusiasts seem to exaggerate their noise somewhat (esp compared to the front coach of an HST)

 

[AndyLandy]

No it doesn't solve that particular one at all. As i have pointed out elsewhere, the peak loads west of Oxford and Swindon can fill HSTs now, so however any future train is powered, you will be sending long formations all the way.

So at peak times, drag both units? Or run 1x9-car at peak times and 2x5-car off peak with a split at Oxford?

However we're solving this with IEP, I think it's fair to say that a loco-dragged solution could drag the equivalent units. Of course, that doesn't get around all the other issues with loco drags, but I don't think this particular one is a big deal.

 

[corfield]

As I said, bi-mode strikes me as an engineer, as the right answer. A purpose designed e-Voyager in fact.

It offers:

1) flexibility of go-anywhere, regardless of wiring spread progress and pace.

2) avoids the need for a wasteful specialised class of diesel locos that are inflexible in their location (especially coping with change due to electrification) and detrimental to current timetable times/frequencies through reduced numbers of powered axles. Nice theories about reusing the locos are fancifully wasteful as we have no shortage of modern heavy freight locos, they seem unsuited for freight anyway and all of that future use prediction is based on absolutely zero evidence or confidence it will be true on the day in the future - it doesn't survive the first moment's reflection of a business case assessement. Freed up engines on the other hand can have a virtually guaranteed 2nd hand usage - a few months back I was involved in the installation of a mixure of 2nd hand engines into a remote location generator facility in Afghanistan. There is a strong market for engines in this class to be used in a huge range of applications globally (especually where new, speialised solutions are unaffordable as is often the case in developing countries).

3) matches current 22X comfort wrt underfloor noise, an issue hugely over egged by obsessive enthusiasts and barely noticeable to 99% of travellers, whilst eliminating it on electrified sections. I travelled on a crammed 4-car 220 yesterday, luckily got a seat as the door stopped opposite me, and I completely forgot about it other than in the first few minutes when I was reflecting on this very issue. Underfloor engines are a non issue for all but a tiny minority of people, most of whom I suspect hardly use the services and who are thus of little to no relevence to the modern railway system and it's future. I also suspect if this was eliminated as per their wishes, they'd find something else to vociferously complain about instead as it is their nature that is the problem, not the train's.

4) The diesel system coming in at 5-10% of weight (less?) is irrelevent to being carried around, and the overall train is still lighter than peer EMU/DMUs, and much lighter than EMU+loco wrt track charges.

The overriding requirement on UK railways is to shift existing/increasing numbers of people and give them the seat for which they've paid. Not to reduce capacity and journey times or increase procurement (multiple classes of things) and operational (manning) costs.
Your proposals utterly fail to acheive the former, at the expense of the latter, all in the name of a specious and frankly unnessecry level of comfort that only you seem interested in.
It is better 100 people get a seat, any seat, than 60 get a seat much wider than they are and perfectly aligned with a window most wont look out of. We need maximum numbers of travellers to pay the fares, and to do what we can to keep fares down so the system is open to all. Not as you seem to intend, reducing capacity and raising costs so that only the wealthy can travel and thus give them a commensurate comfort level. If you want more space, go 1st class or use VSOE, or better still, start your own open access operator with the locos and coaches you love and see how quickly it goes downhill.

As I said before - I originally supported an EMU+loco. Now, I'm firmly in IEP & bi-mode camp. Perhaps you should reflect on the persuasiveness of your arguments vs. those of others, and consider that your "1950s in the 21st Century" railway dream has no bearing on reality.

Enough said.

(See, other people can also try and cut others off to give themselves the last word).

 

[tbtc]

I think it's fair to say that a loco-dragged solution could drag the equivalent units. Of course, that doesn't get around all the other issues with loco drags, but I don't think this particular one is a big deal.

Beyond the wires, the services we are talking about tend to stop at most stations (Edinburgh to Aberdeen/ Inverness, Oxford to Hereford etc), so tend to be a lot more "stop start" than the electrified sections will be.

Whilst a "68" may be able to haul a 390, I'm not convinced that it'll be able to match the timings of a bi-mode

(yes, I appreciate that we are arguing about whether one hypothetical train would be better than another, and neither is running yet, this is all highly subjective, but I'm trying to say that being able to drag eleven coaches is only part of the story)

 

[Murph]

Maybe your hearing is better than mine, but I'm never bothered by underfloor engines - some enthusiasts seem to exaggerate their noise somewhat (esp compared to the front coach of an HST)

Underfloor engines don't bother me on short-distance services, but I do feel that the current ECML IC125 / IC225 fleet is vastly superior in terms of noise and vibration for long distance. That's compared to a variety of 15x, 17x, 22x journeys that I've been on. I can't deny that it's less than silent if you're in a coach next to a HST power car, but the remainder of the set just glides along beautifully (assuming it's well maintained).

If push comes to shove, I've slept with my head about 24" away (and approx 2" of acoustic insulation) from a Perkins 4.108 running at about 2000rpm, so running diesels don't bother me as such, it's just nicer when they are not constantly beside you. I just really appreciate the refinement and mechanical silence of the Mk3/Mk4 IC coaching stock, and feel it's a significant difference in quality of service to any of the DMUs for long distance travel.

I'm also sceptical about the relative fuel efficiency and maintenance costs of many small diesels compared to 1 or 2 big diesels in an 8-10 car formation. That's just "gut feeling" that a couple of big diesels should be the optimum in terms of running costs (and any fair comparison would need to be same generation/technology level for both big & small — can't compare a 1970s Valenta to a 21st century small engined set), can't say for certain what the truth will be without doing a lot of research.

 

[AndyLandy]

As I said before - I originally supported an EMU+loco. Now, I'm firmly in IEP & bi-mode camp. Perhaps you should reflect on the persuasiveness of your arguments vs. those of others, and consider that your "1950s in the 21st Century" railway dream has no bearing on reality.

Quoted for Truth™

I (like many other pro-IEP folks here) started out in favour of EMUs+loco drags. It's only having actually read through all the details and the arguments in both directions that I'm firmly in the bi-modal camp these days.

Beyond the wires, the services we are talking about tend to stop at most stations (Edinburgh to Aberdeen/ Inverness, Oxford to Hereford etc), so tend to be a lot more "stop start" than the electrified sections will be.

Whilst a "68" may be able to haul a 390, I'm not convinced that it'll be able to match the timings of a bi-mode

(yes, I appreciate that we are arguing about whether one hypothetical train would be better than another, and neither is running yet, this is all highly subjective, but I'm trying to say that being able to drag eleven coaches is only part of the story)

Oh, I agree. I sincerely doubt a 68 will be able to keep to bi-mode timings. I think the only point I was getting at is that it's theoretically possible to haul either 1x5-car, 2x5-car or 1x9-car EMUs with a locomotive, so you could still balance for passenger loads; not necessarily that it's a good idea!

 

[Kali]

Engine noise doesn't bother me on 159s either, and that is an intercity-length route. If you can make a car practically silent with the engine a couple of feet in front of you then there's no reason you can't make a train the same. Can and will are of course different matters...

There's no reason you can't drag/push a diesel using the EMU ( which is what bimode is doing anyway ) which renders the objection to shifting switchover points/placing maintenance facilities a bit moot. It just depends if it's more economical to cart the diesel around some of the time, or all of the time. You could literally put the same underfloor engine/generators in a single box and call it a locomotive, if you want - genset units like that are existing devices.

 

[jimm]

So at peak times, drag both units? Or run 1x9-car at peak times and 2x5-car off peak with a split at Oxford?

However we're solving this with IEP, I think it's fair to say that a loco-dragged solution could drag the equivalent units. Of course, that doesn't get around all the other issues with loco drags, but I don't think this particular one is a big deal.

Never said it couldn't haul a long formation, but what is the performance going to be like? As tbtc says, can it match IEP timings? Or even those of an HST now?

At no point in my posts have I suggested that I think a bi-mode IEP is going to be the greatest thing since sliced bread. I would love to be able to ride everywhere on a shiny new electric train but no matter how often some people post here that 'they' just should wire everywhere in Britain in one fell swoop, it's not going to happen.

But on the other hand, I'd rather have something like the bi-mode than bet the farm on coupling and uncoupling diesel locos all day long. No matter how much in favour of them some commentators on the industry are, like former big diesel loco engineer Mr Ford.

Given that you cannot finance new dmus now, because banks cannot see a long-term use for the things, why would they fund a small fleet of bespoke diesels - and they will need to be bespoke, be in no doubt about that, with auto-couplers and geared for fast acceleration and running, not a mixed-traffic compromise like a 67 or 68 - with equally murky long-term prospects? Answers on a postcard.

 

[RobShipway]

For me as a passenger whether it is short or long haul journey, the bi-modal is the best idea and like many here I would have preferred the romance of being on a loco hauled train, however you have to be realistic in the fact that there are less and less points in Stations and sidings on the network where a diesel can be stabled, so IEP with its built in diesels I truly believe is the best answer. This is especially so given the recent snowy weather most of the country has had in the last week.

Those against IEP bi-modal, please ask yourself if the OHLE electrics where turned off due to severe cold weather like we have had recently, but the track was still clear for trains to travel how would the IEP work then?

Would you really expect passengers as has been the case a few times in this last week to be waiting 5 - 6 hours like the passengers that got stuck just outside of Lewes in a 313 which had to be recovered by a class 73 I believe from Stewarts Lane?

At least with the IEP bi-modal the train if it is under the OHLE and the power is turned off, could at least rescue itself with the underfloor diesel engines.

My only question about the IEP bi-modal train, is that in such situations as above please have them be designed so that they can also help with the rescue of the non bi-modal trains with their diesel power if possible Hitachi?