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IEP for beginners

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Zoe

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Which routes that it would run on the diesel engines would it need more than that?
I can't think of any, the only section I can think of where 125 mph has even been proposed is Bristol to Bridgwater and even then, the Weston services would not use all of this section.
 
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RobShipway

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Which routes that it would run on the diesel engines would it need more than that?

Any routes where 125mph is the maximum speed where it goes beyond the wires such as pass Newbury on the line down to Exeter and the South West.

Is there also a section of 125mph north of Oxford when going towards Hereford etc..?
 

asylumxl

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Any routes where 125mph is the maximum speed where it goes beyond the wires such as pass Newbury on the line down to Exeter and the South West.

Is there also a section of 125mph north of Oxford when going towards Hereford etc..?

IEP is not supposed to running on the SW services though. They will remain HSTs for a while longer I believe.
 

455driver

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A class 43 at 28.18ppm plus a DVT at 10.60ppm plus say 10 mark 3 coaches at 6.53ppm each that comes to 104.08ppm.
Wouldnt get above about 50mph and the 43 traction motors would overheat/ explode.

Compare this to a Class 67 and 10 mark 4 coaches and a DVT it works out at 172.82ppm
Sounds good.

Compare this to an 11 coach voyager and it costs 96.25ppm.
Still yuck though unless you give them a decent interior.

Alternatively an 11 coach Pendolino would be 150.1ppm
Still a horrible train compared to a decent mark 3.

and as has been said before IEP will require LESS coaches per train to maintain the same capacity, which potentially reduces the track access charges.
But IEP coaches will be heavier and the heavier they are the more you pay.

TAC is worked out by vehicle weight, number of axles and suspension geometry, I cannot see the IEP elephant being very light on its feet/ nice to the track.
 

AndyLandy

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TAC is worked out by vehicle weight, number of axles and suspension geometry, I cannot see the IEP elephant being very light on its feet/ nice to the track.

Didn't we do this bit already? The IEP bi-mode vehicles are going to come in weighing less than Voyager ones. So, one would expect the TAC to be slightly lower, too.
 

455driver

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What's Laira got to do with it? There's no suggestion at this stage that IEP is going anywhere near Devon. .

Oops I forgot the South West is lucky enough to be keeping the HSTs arent they.
 

Zoe

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Any routes where 125mph is the maximum speed where it goes beyond the wires such as pass Newbury on the line down to Exeter and the South West.
There are no 125 mph sections between Bristol and Penzance or Reading and Cogload Junction.
 

Dave1987

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Not a snowball in hell's chance they could keep to HST timings on a route like the Cotswold Line

And there is not a chance that IEP bi-modes could keep to HST timings, whereas a loco could! As the experts have said bi-modes will be very slow at accelerating so journey times will be longer.
 

ainsworth74

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Can we get a source to verify the statement that bi-mode is going to be slower than HSTs in terms of acceleration?
 

jimm

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Oops I forgot the South West is lucky enough to be keeping the HSTs arent they.

Oops indeed. Now perhaps you could explain how you propose to keep these diesels fuelled and serviced, miles from suitable depots?

And there is not a chance that IEP bi-modes could keep to HST timings, whereas a loco could! As the experts have said bi-modes will be very slow at accelerating so journey times will be longer.

Funny, because some people seem very confident IEP can improve on HST times, whatever the "experts' say. Much of what the 'experts' said was actually about previous incarnations of the IEP, but don't let that get in the way of your permanent negativity, will you?

And where is the loco that can do all these things you claim for it?

Unsurprisingly, yet again you have just ignored everything I've said about what operating locos will actually involve for the Cotswold Line. How far from doing a few miles a month, these locos would be hammered up and down, day in, day out, miles from a major depot.

Just for once, try to break this habit of yours and actually explain how your preferred option is going to work in the light of all those issues I raised? How are you going to overcome them, if using locos is just so much easier?

Maximum speed currently permitted on the Cotswold Line is 100mph between Wolvercot junction, north of Oxford, and Ascott-under-Wychwood. Network Rail has been looking at the possibilities for increasing speed limits along the route in connection with the introduction of IEP, including 100mph-plus in places.
 

Metrailway

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Can we get a source to verify the statement that bi-mode is going to be slower than HSTs in terms of acceleration?

The Foster report (http://www.railwaysarchive.co.uk/documents/Foster_IEPReview2010.pdf and http://www.railwaysarchive.co.uk/documents/Foster_IEPReviewAnnex2010.pdf) states:

In relation to IEP specifically, the concern centres on the capability of a single diesel generator carriage to power long-distance through-trains (i.e. trains which will also have pantograph/transformer carriages), especially in the often hilly regions in Scotland and the South West peninsula where they would be most called upon in the absence of electrification. Although Agility Trains have committed to contracting to deliver the required journey times, our analysis of IEP bi-mode performance (distance speed graphs) causes concern around the technical capability of the train to deliver these journey times.

...

A number of experts have doubts about the bi-mode’s likely performance, particularly in the hillier ‘off-wire’ regions where they will be called upon the most. Surprisingly, I found that there would even be increases in some journey times.

....

From the IEP performance simulation evidence we have seen, some overall journey times may be improved where the greater proportion of the journey is with electric power. The services from London to Weston-super-Mare are such an example. However, many local and some longer distance journey times are calculated to be longer than today’s trainswhere diesel power is used, especially in the hillier terrain such as north of Edinburgh to Aberdeen and Inverness, or to Devon and Cornwall. This seems counterintuitive.
 

asylumxl

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Interesting to note, Foster writes a report about IEP and makes those claims, yet isn't aware they will not be going to the SW?

Also, he will write whatever the administration wants him to.
 

ainsworth74

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As Zoe notes Foster is pretty out of date at this point. I, personally, wouldn't discount his broad conclusions but I suspect a lot of the specifics are now questionable. So anything more recent?
 

Zoe

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Interesting to note, Foster writes a report about IEP and makes those claims, yet isn't aware they will not be going to the SW?
I'm not sure it had been decided for certain back then. The South West was an option on the contract and the decision to retain HSTs wasn't announced until 2011 by which time it was decided that bi-mode would use underfloor engines and the diesel only IEP plan was abandoned.
 

RAGNARØKR

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Can we get a source to verify the statement that bi-mode is going to be slower than HSTs in terms of acceleration?
Depends on the bi-mode, surely? What is the power/weight ratio of the trains?
--- old post above --- --- new post below ---
Forgive me if I take things he says with a pinch of salt.

In reality acceleration is very important for the IEP, especially in places where the line speed can't be increased. Quicker acceleration and the resulting higher average speed is the obvious solution to reduce journey times further.
He drew attention to a thing called the "constant power curve", which is the limiting factor in acceleration with diesel except on start-up. Whatever you may think of RF, that statement is to be relied on. The implication is that a as the speed rises above about walking pace, there is a limit to the amount of power that is available to be put down at the rail, so that distributed drive wins nothing except when stops are frequent. Voyagers have good acceleration all the way up the speed range because of the high power/weight ratio but the result is to make them into gas guzzlers.
--- old post above --- --- new post below ---
TAC is worked out by vehicle weight, number of axles and suspension geometry, I cannot see the IEP elephant being very light on its feet/ nice to the track.
Hasn't the IEP got negative mass?
 

Kali

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It'd have to be horrendously slow to accelerate slower than a HST. Something like a full 9 car unit hauled by a 67 ( which like a HST also has terrible tractive effort ) to pop that idea...

Distributed power keeps the axle loading down also. Why are people considering a 68 for haulage? you'd never realistically use any of these drag locomotives for freight, multipurpose is a red herring. Design the train + drag/offwire power unit as a coherent system from the outset.
 

swt_passenger

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Can we get a source to verify the statement that bi-mode is going to be slower than HSTs in terms of acceleration?

I think (but have nothing to prove it) that much of the original criticism of the bi-mode dates back to the original plan for a 10 car version of the bi-mode train with a power car at only one end. The published info showed it having the same power unit as a 5 car bi-mode, and Roger Ford gave it the ridicule it deserved.

Since those times they have binned both end power cars and 10 car bi-modes, so I think the bi-mode power 'issue' has been completely overtaken by subsequent design changes...
 

jopsuk

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Thanks to the documents (specifically, the Anglia route ones) linked from this post there's now possible class numbers for IEP- there is mention Classes 800 and 801 from IEp in relation to the length of train Cambridge can handle on platforms 7 & 8, suggesting that even those (which are longer than a 12 car 379/365 by some way) may need extended (for which there is, as noted, lots of space).

No idea which varients 800 and 801 respectively will be.
 

RAGNARØKR

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Any new stock would come with inflated costs - either through PFI procurement or the high profits that ROSCOs take. That's not specific to IEP.
The inflated costs arise in the first instance from the specification. Bi-mode just helps to pile on more costs still. The inflated cost of new stock is also a very good reason for refurb and keeping old vehicles going for as long as possible.
Have you abandoned your suggestion of doing the loco swapovers at Haymarket?
Because of the difference in loadings north and south of Edinburgh either the train needs to be split somewhere near Edinburgh or it will be running half-empty beyond Edinburgh. And if the train is to be split, then it might as well run loco-hauled for that part of the route.

If it is really impossible to split the train at Edinburgh then the handful of trains between London and Aberdeen might as well be diesel throughout. Either way it eliminates the need for bi-mode altogether.
 

HSTEd

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The inflated leasing charges for new stock will translate to inflated leasing charges for existing stock.

The ROSCOs like to make money.
 

The Ham

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But IEP coaches will be heavier and the heavier they are the more you pay.

TAC is worked out by vehicle weight, number of axles and suspension geometry, I cannot see the IEP elephant being very light on its feet/ nice to the track.

However as I stated there will need to be less coaches, so even if each coach costs more because they are heaver, say 16.6ppm for IEP compared with 13.6ppm for a Pendilino, it works out comparable per train (9 coaches of IEP and 11 coaches of Pendilino)
--- old post above --- --- new post below ---
All you are going on about is track access charges. What about the £80,000 per train per year in hauling around the dead weight of the bi-modes engines under the wires eh? What about the fact underfloor engines are less fuel efficient than modern locos? The class 68 is said to be the most fuel efficient, least polluting loco ever. And will be able to run at 100mph with freight or passenger trains. The weight of a pendo style train would be nothing for one of these considering they will have 3,750hp/2,800kW. The bi-mode will be slow to accelerate and will struggle up hills. A loco like the class 68 will accelerate quicker and wont struggle on hills.

I am talking about track access charges because the track access charges for electric trains INCLUDE the electricity. Therefore the £80,000 that you are so keen for us to "save" would be included in these charges. For IEP to be comparable in track access charges alone to the existing HST's it would need to cost less than 12ppm per coach, however the IEP track access charges include fuel, so it can cost a little more than that.

To be comparable to the IC225's it could cost 17ppm per coach.
 

RAGNARØKR

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I am talking about track access charges because the track access charges for electric trains INCLUDE the electricity. Therefore the £80,000 that you are so keen for us to "save" would be included in these charges. For IEP to be comparable in track access charges alone to the existing HST's it would need to cost less than 12ppm per coach, however the IEP track access charges include fuel, so it can cost a little more than that.

To be comparable to the IC225's it could cost 17ppm per coach.
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.
 

LexyBoy

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I do find it mildly amusing the amount of discussion about comparative costs of IEP vs various alternatives. If there was one metric which I would be confident the DfT had rigorously detailed (and actually have the figures for), it would be cost.

There are plenty of other things to debate. For example, would people's proposed alternatives to IEP also be
pointy and fast.
 

Dave1987

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I am talking about track access charges because the track access charges for electric trains INCLUDE the electricity. Therefore the £80,000 that you are so keen for us to "save" would be included in these charges. For IEP to be comparable in track access charges alone to the existing HST's it would need to cost less than 12ppm per coach, however the IEP track access charges include fuel, so it can cost a little more than that.

To be comparable to the IC225's it could cost 17ppm per coach.

Sorry just done some research on this. And from what I have read electric is not included in track access charges.
 
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