Intercity Express Programme (IEP) - ongoing discussion

[whole diary]

[paul7575]

A DfT^» (Department for Transport - about) written answer to PMQ has finally confirmed the expected delivery of all GW^▸ (Great Western) IEPs^▸ (Intercity Express Program / Project.) as bi-mode variants:

Following the receipt of a formal proposal from Agility Trains West Ltd, My Rt Hon Friend, the Secretary of State for Transport has now approved the conversion of the 21 Class 801 Intercity Express Programme units scheduled for deployment on the Great Western to bi-mode operation. This will enable passengers in the South West and Wales to benefit as soon as possible from brand new trains which will deliver more capacity and more comfort. The first 36 trains will be bi-mode as planned.

http://www.parliament.uk/business/publications/written-questions-answers-statements/written-question/Commons/2016-05-18/37456/

[JayMac]

What of their top speed capability? Will the diesels be uprated to run at 125mph where line speed allows. Or will the 'benefit as soon as possible' be slower journey times?

[IndustryInsider]

What of their top speed capability? Will the diesels be uprated to run at 125mph where line speed allows. Or will the 'benefit as soon as possible' be slower journey times?

Provided the wires are up as far as Bristol Parkway at least then I reckon a bi-mode running on diesel will match or beat the point-to-point timings, and beat the station dwell times of the current HST^▸ (High Speed Train) fleet west of BPW^» (Bristol Parkway - next trains). I doubt they'd be huge differences east of there as well - especially if the extra trains with fewer stops can operate as planned.

[John R]

What of their top speed capability? Will the diesels be uprated to run at 125mph where line speed allows. Or will the 'benefit as soon as possible' be slower journey times?

I seem to recall confirmation a few months ago that they would be running at 125mph, although I can't put my finger on where at the moment.

[stuving]

What of their top speed capability? Will the diesels be uprated to run at 125mph where line speed allows. Or will the 'benefit as soon as possible' be slower journey times?

I seem to recall confirmation a few months ago that they would be running at 125mph, although I can't put my finger on where at the moment.

It was in parliamentary answers - see here. Basically, if there is enough power to run at 125 mi/hr, given the gradient, the train will do it when asked to.

But note that was said of class 800s, not 9-car bi-modes (whatever class they are). That statement should apply in both cases, but the power needed and available are both different. Three engines per 5 cars is a little more than five per nine cars, but then the drag per car is less for the longer train. So it's not clear which would run faster overall.

[grahame]

In the longer term, "all GWR^▸ (Great Western Railway) IEPs^▸ (Intercity Express Program / Project.) are bimode" does allow for diversions of Bath and Bristol trains via the Berks and Hants, and Paddington trains into Waterloo or Marylebone when there's ongoing engineering, signal problems between Swindon and Chippenham, or one of those too-frequent 'person hit by train' incidents on the normal run into London.  Of course, once the current engineering's completed, there will be nothing to do done for a further 30 years and then we'll get another backlog.     Also relieves the cascade / releases HSTs^▸ (High Speed Train) to Scotland, and has us some bright shiny new trains in places like Chippenham and Bath by May 2020 - not that that would have been a consideration at all.

[ellendune]

Another scenario is that as electrification is completed and extended, the bi-modes are cascaded onto other part electrified routes and replaced with new all electric trains.  Particularly as, I assume, that the bi-modes are more expensive than all electric.

[IndustryInsider]

It's in the spec that bi-modes can have their engines removed (bar one) and become easily converted to electric units.  I should imagine that is what will happen when the wires reach Swansea and Temple Meads via Bath.

[Noggin]

It's in the spec that bi-modes can have their engines removed (bar one) and become easily converted to electric units.  I should imagine that is what will happen when the wires reach Swansea and Temple Meads via Bath.

I was going to say that they could be cascaded to cross-country or another franchise, but remembering that they are the initial batch procured by the DfT^» (Department for Transport - about) that were a lot more expensive and of a lesser spec than the AT300s, then I suspect you're right and they'll just have their engines removed. 

[broadgage]

What is the maximum length IEP^▸ (Intercity Express Program / Project.) that can run in passenger service ?

I appreciate that train lengths are unlikely to routinely exceed 10 vehicles, partly due to platform length limitations. But would the odd 5+5+5 or 9+5 formation be possible ?

The ability to run the odd extra length train at especially busy times could be valuable. Something like 14 or 15 coaches from Paddington to Taunton with 5 vehicles being detached at Taunton.
AFAIK^▸ (as far as I know) one platform at Paddington can take 15 coaches, I recall Diesel loco+14+steamer and tender.
Taunton has plenty of room.

I have previously doubted that enough stock will be available to ensure that all busy services are full length, but of course more might be ordered ? With rapidly growing passenger numbers and a limited number of paths, longer trains are going to be more needed.

Also is it yet known if the IEPs and the AT300s will be able to run in multiple ?

[John R]

Quail would seem to imply that Taunton, Exeter St D and Plymouth could take the longer trains. So platform length may not be a limitation, although other operational aspects and technical aspects of the train could still be.

[stuving]

What is the maximum length IEP^▸ (Intercity Express Program / Project.) that can run in passenger service ?

The requirement for passenger workings is quite simple:

3.2 Multiple working
TS231 All IEP Trains must deliver full Multiple Working in normal passenger service with other IEP Trains (of any type) within the following constraints;
^ Up to a maximum of two IEP Units; and
^ Up to a maximum total multiple length of 312m.
And when operating in Multiple Working within such constraints, there shall be full control of such systems throughout the train that are capable of being controlled from the cab of a single IEP Unit such that there is no difference in functionality between a single IEP Unit and an IEP Train formed from two IEP Units coupled together.

312 m is 12-car length, of course. However, as always with specifications, nothing requires longer trains not to be possible should the supplier wish to provide for that.
(There are much more complicated requirements for rescue with mixed types.)

Also is it yet known if the IEPs and the AT300s will be able to run in multiple ?

I guess that would depend on the contract for the newer trains, but it would be very odd of they are not "IEP Units"s in the sense used above.

[IndustryInsider]

Quail would seem to imply that Taunton, Exeter St D and Plymouth could take the longer trains. So platform length may not be a limitation, although other operational aspects and technical aspects of the train could still be.

According to the Sectional Appendix, Paddington's longest platform is 307m, Exeter's is 323m, and Plymouth's is 300m.  Though the operational length would likely be shorter when you consider the location of signals, stopping margins, and so on.  A 10-car IEP^▸ (Intercity Express Program / Project.) train weights in at around the 255m mark, so I would doubt that would ever be exceeded in the short to medium term given the number of locations available for longer and the number of platforms at those locations that would be suitable.

[SandTEngineer]

Paddington Platforms 1-5 starting signals are going to be moved out to allow longer trains to use them. Need to dig out the signalling scheme plan to check by how much though......

[John R]

Quail would seem to imply that Taunton, Exeter St D and Plymouth could take the longer trains. So platform length may not be a limitation, although other operational aspects and technical aspects of the train could still be.

According to the Sectional Appendix, Paddington's longest platform is 307m, Exeter's is 323m, and Plymouth's is 300m.  Though the operational length would likely be shorter when you consider the location of signals, stopping margins, and so on.  A 10-car IEP^▸ (Intercity Express Program / Project.) train weights in at around the 255m mark, so I would doubt that would ever be exceeded in the short to medium term given the number of locations available for longer and the number of platforms at those locations that would be suitable.

Ah, just looked at the notes for Quail, and they are based on a 20m nominal length per car.  So somewhat misleading when considering a 26m IEP!