A Class 172 bi mode?

[150001]

With the age of the Pacers and Sprinters rising ever higher with the DDA deadline looming, are we ever going to replace them. With electrification now due but other types of electric stock also becoming older, aren't we going to need a new train? The 172s for London Midland are excellent along with the CAF 4000s with NIR. Would it be possible to have bi mode versions of these to replace the Sprinters and Pacers which given the rest of their lives' isn't going to be over 15 years (you'd hope) are perhaps money going down the drain to convert already old trains when new ones much more adaptable plus new could be bought.

Really is it cheaper to buy a bi mode fleet of 172s and 4000s which can be made electric only at a later date, or to continue to modify and maintain older stock with a shorter lifetime left. I'm not including the 156s as they are still looking pretty good for their age!

 

[anthony263]

I have often wondered if a bi-mode version of the electrostar could be built especially it it would save running diesels under the wires and stop some services being split such the Cardiff - Portsmouth Hbr route or even Maesteg - Cheltenham

 

[jopsuk]

the drive system would have to be entirely different- 172s are driven directly from the engine through a mechanical transmission that works on the same principle as those in cars (15x, 16x, 170, 171, 175, 180 and 185 all use hydraulic transmissions that are rather different, but still not bi-mode compatible).

For bi-mode, you need electric drive- as found on 2xx multiple units. On these, the engines turn alternators that produce electricity that's then fed to the motors. On a bi mode, there's "simply" a second power feed, be it DC or AC derived, that can output the same power profile (DC, single phase AC, three phase AC- whatever) as the alternator.

The SNCF bi-modes take advantage of the loading gauge and the need for an accessible low floor to put to the diesel engine, alternator and electrical systems on the roof. On british units you'd have to get all of that on the under frame- but if you look at turbo- and electro-stars, you'll see precious little space.

 

[IanXC]

The 172s for London Midland are excellent along with the CAF 4000s with NIR. Would it be possible to have bi mode versions of these to replace the Sprinters and Pacers which given the rest of their lives' isn't going to be over 15 years (you'd hope) are perhaps money going down the drain to convert already old trains when new ones much more adaptable plus new could be bought.

The 172s have mechanical transmission (hence a TOPS number in the 1xx series), Project Thor (bimode 220s) is only viable because they have Diesel Electric Transmission, so the overhead power can substitute for the diesel generators.

Edit: beaten to it while changing trains!

 

[150001]

I'll rephrase; a 172 outer shell design then with a diesel electric drive.

 

[cj_1985]

I'll rephrase; a 172 outer shell design then with a diesel electric drive.

in theory it could be possible (like so many other things)... but there are too many variables to give a definitive yes or no answer.... ie. cost, equipment placement, weight etc

to get a definitive answer you would need to have plenty of detailed conversations with NR, a ROSCO and whoever you want to manufacture your "EDMU"

 

[TheWalrus]

Hopefully they will do something like this, would be good if Paignton-Exeter got electrified but not Exeter-exmouth.

 

[DXMachina]

could always couple a single-car sprinter to a single-car EMU with compatible multiple working I suppose. Wasteful in terms of duplication and dragging dead systems but you'd only have to build one new vehicle...

 

[rf_ioliver]

could always couple a single-car sprinter to a single-car EMU with compatible multiple working I suppose. Wasteful in terms of duplication and dragging dead systems but you'd only have to build one new vehicle...

Why not do as the Danes and couple diesel and electric trains together?

I'm not sure of some of the specifics but certainly one could calibrate the control systems to each of the units is matched in terms of power output (to rail)...?

Ok, so this is really useful when you have services which need to be coupled. For example I could see this happening with services from the South West to Wales...diesel from Portsmouth coupling with an electric service from Bath, then on to Cardiff...?

t.

Ian

 

[Donny Dave]

I asked on WNXX a long while ago now about the viability on coverting 185s to bi mode.

The short answer is that for an DMMU stock, it's probably just as cheap to order new stock as you have to completely gut each carriage and start again.

While the idea of converting the likes of 170/172/185 is a good 1, unfortunately, we'll be stuck with them as they are until they are withdrawn.

 

[bronzeonion]

Thumper MK2 anyone?

 

[D365]

By the time you've rebuilt the entire thing, it won't be a 172. It really wouldn't be worth it compared to new stock. Haven't we had a similar discussion here already?

 

[150001]

I repeat; 172/2 and 172/3 outer styling; not equipment or engine. Just the actual shell. It would n't be a Class 172 but just have a similar body design.

 

[D365]

A 272 or similar, I guess. The shorter-distance DEMU idea has been discussed in quite some detail here.

 

[BananaRepublic]

The DafT had a programme for a modern new local/regional DMU to replace the Pacer and some of the Sprinter fleets.

The programme was born from the recognition that not only would these trains need replacing in due course, but with the uncertainties over the future of diesel fuel, any likely electrification programmes (not known at the time) and EU emissions laws, it was very unlikely that any ROSCO or TOC would would be prepared to take the financial risks involved.

The "New DMU" programme included the establishment of a DfT backed ROSCO specifically created to finance this new train fleet.

The "New DMU" programme was cancelled when it became clear that a rolling electrification programme would be forthcoming. However, a couple of years on, we now know the timetable and extent of initial electrification plans and can see that future extensions to the programme will take a least another decade to complete.
That indeed leaves a gap where the Pacers and earlier Sprinters will be well beyond their sell by dates.

Time may be running out for the prospect of new DMU orders, but then again, will some parts of the network ever be considered for electrification?
Bi-Mode may well be the medium and long term answer for some parts of the network?

 

[JohnB57]

The 172s for London Midland are excellent along with the CAF 4000s with NIR.

Really is it cheaper to buy a bi mode fleet of 172s and 4000s which can be made electric only at a later date, or to continue to modify and maintain older stock with a shorter lifetime left. I'm not including the 156s as they are still looking pretty good for their age!

Is there some relevance to the OP's comment regarding the NIR 4000s that I have missed? What use would a bi-mode 4000 be?

 

[junglejames]

With the age of the Pacers and Sprinters rising ever higher with the DDA deadline looming, are we ever going to replace them. With electrification now due but other types of electric stock also becoming older, aren't we going to need a new train? The 172s for London Midland are excellent along with the CAF 4000s with NIR. Would it be possible to have bi mode versions of these to replace the Sprinters and Pacers which given the rest of their lives' isn't going to be over 15 years (you'd hope) are perhaps money going down the drain to convert already old trains when new ones much more adaptable plus new could be bought.

Really is it cheaper to buy a bi mode fleet of 172s and 4000s which can be made electric only at a later date, or to continue to modify and maintain older stock with a shorter lifetime left. I'm not including the 156s as they are still looking pretty good for their age!

No point ordering new stock until something really is life expired. If you keep replacing none life expired stock, it will eventually turn into a very expensive game. Also bare in mind that new stock is rarely built to last as long as older stock. This older stock may last longer than you imagine.
For example its debatable whether Mk3s need replacing. Chilternising them would be a lot cheaper than replacing them, and you would no doubt see at least another 15yrs from them. Not far off half the lifespan of a newbuild. But thats the good thing about hauled stock. Its like all these people claiming 225s need replacing. Crikey, the Mk4s have another quarter of a century left in them.

Regarding pacers and sprinters. Pacers yes. They need replacing soon. But i cant think of any of the sprinter fleet that need replacing. None of them strike me as ready for the scrapper.
As for what should replace pacers. Is bi mode really necessary? You are adding extra complexities into the design, but for what benefit? I cant think of anything that pacers do which would warrant the extra cost and maintenance. There needs to be a decent long stretch under the wires to make it worthwhile. 5 or 10 miles here and there doesnt really make it worthwhile.

The 185 fleet could probably do with being replaced by a bi mode fleet once electrification is complete. The 185s could then go someway to replacing the pacers. Cant see anymore bimodes needed though.

 

[Nym]

As for what should replace pacers. Is bi mode really necessary? You are adding extra complexities into the design, but for what benefit? I cant think of anything that pacers do which would warrant the extra cost and maintenance. There needs to be a decent long stretch under the wires to make it worthwhile. 5 or 10 miles here and there doesnt really make it worthwhile.

Manchester Airport to Southport via Bolton:
Half and half with all performance critical sections under the wires.

Manchester Victoria to Wigan Wallgate / North Western via Bolton:
As above.

Manchester Piccadilly to Buxton:
Not pacers directly, but with the same result and using a diesel on the non-critical section of the route.

Liverpool Central to Preston:
Re-open the route to be a through service at 2tph extending from Liverpool onwards to Preston, a 3 coach EDMU design works well, passing loops can be provided, again, all time critical sections are electrified.

Liverpool Central to Southport via Borcough Curves:
Kick starting curves to re-open, augmenting a pacer operated service on part of the route.

Liverpool Central to Wigan Wallgate via Kirkby:
Again, a half hourly extension by re-instating through service and providing passing loops.

Newcastle to Middlesbrough:
Different kind of EDMU here, running off 1500V DC where Metro infrastructure is provided, 25kV AC where available, and diesel elsewhere, this would be a variation on a design that could be used for Merseyrail Electrics and South West Trains, with a small modification to the power electronics module for the DC pickup and pantograph arrangments.

Leeds to Carlisle:
Similar to MIA to Southport, non-critical sections on Diesel, roughly half and half by track mileage.

This enough suitable routes yet or do I need to start on SWT and Southernland, and add in the CH services that run on LUL infrastructure electrified (shortly) at 750V DC...?

 

[starrymarkb]

There are also BioFuel Powered Emu's available
Or an older model
I'll get my coat

 

[aylesbury]

You will be lucky the 172,s are probably the last dmu,s to be built and a bimode version is an expensive waste of money.Electric is the way forward and even then new builds are going to be slow coming into service and probably not work properly .Chiltern,s 172 ,s are only used to Gerrards X because of their top speed being lower than a 168 thus getting in the way of fast services beyond GX .The LM units are fine in the midlands because of low overall speeds and an improvement on the 150,s thank god .Eventualy the lines in the midlands will be electrified and the 172,s will be cascaded to Cornwall?

 

[Donny Dave]

You will be lucky the 172,s are probably the last dmu,s to be built and a bimode version is an expensive waste of money.Electric is the way forward and even then new builds are going to be slow coming into service and probably not work properly .Chiltern,s 172 ,s are only used to Gerrards X because of their top speed being lower than a 168 thus getting in the way of fast services beyond GX .The LM units are fine in the midlands because of low overall speeds and an improvement on the 150,s thank god .Eventualy the lines in the midlands will be electrified and the 172,s will be cascaded to Cornwall?

Eh? Chilterns allocation of 172s have a top speed of 100mph, the same as a class 168!

 

[150001]

OK, the Sprinters with a gutted interior would be fine and at Starrymarkb!

 

[Pen Mill]

Here's a French Bi-Mode unit which they have had in service since 2005.
http://en.wikipedia.org/wiki/SNCF_Class_B_81500

Here's the French Wiki which is more informative
http://fr.wikipedia.org/wiki/B_81500
They have a total of 185 units in service in 3 and 4 car formations.
I think they'll have to be at least 3 to accommodate the panto.

Made by Bombardier so jobs for the Brits ?

They also have the B82500 series which the French call the Bi-Bi
That's Bi-Modal Bi-current at 1.5KV DC and 25 KVA
http://en.wikipedia.org/wiki/SNCF_Class_B_82500
They have a further 140 of these making a total of 320 Dual-modal units.


EDIT :

.Electric is the way forward and even then new builds are going to be slow coming into service

You are being wildly ambitious.
Only 40% of the British Network mileage is electrified currently and 1/3rd of that is 3rd rail . The projects on the books have basically filled the books for the next 10 years , GWML, Lancashire etc . MML and even then you'll only be touching 50%

It's taken 50 years to get to here so even with positive enviro-pressure , I'd guess at 30 years minimum before the majority of lines are wired.
You will need Bi-mode or dual-mode if you want to minimise the use of diesel.

 

[Peter Sarf]

I would see pacers replaced by sprinters not necessarily bi-modes. Perhaps bi-modes are more likely to be justified for routes that sprinters run on currently.

But I would rather see electrification reducing the number of diesel trains required enough to mean pacers are surplus. Project Thor (bi-modeing ALL 220s, 221 and 222s) would surely produce enough bi-modes to cover all long distance requirememnts and would have also made a bi-mode IEP unecessary. Then perhaps a new bi-mode for the shorter routes.

If we get the electrfication we deserve will we ever end up with surplus diesels ?.

 

[150001]

Related to 172s, why is this LM 172 on the Cross City line? Running from Hereford?

http://www.youtube.com/watch?v=CPT_P6O784c

 

[Chris125]

You are being wildly ambitious.
Only 40% of the British Network mileage is electrified currently and 1/3rd of that is 3rd rail . The projects on the books have basically filled the books for the next 10 years , GWML, Lancashire etc . MML and even then you'll only be touching 50%

I dont think mileage is a particuarly useful figure, more important is how many services can be switched from diesel operation to electric - a big reduction in the need for DMU's can be achieved with a relatively small percentage increase in wiring.

Chris

 

[sprinterguy]

Related to 172s, why is this LM 172 on the Cross City line? Running from Hereford?

http://www.youtube.com/watch?v=CPT_P6O784c

I've seen a couple of 172s on the Cross City South now, on Sundays, and although I don't know for sure I have assumed that there is a Sunday diagram for them to Worcester/Hereford. It would be good to know for sure.

 

[AndyLandy]

As far as I can tell, there's is little to no appetite for new diesel traction, nor for bi-mode trains. It was explained to me elsewhere on this forum that the R&D costs of a bi-mode would likely far outweigh the benefits.

You'd be far better off looking at sensible ways to cascade stock by replacing diesel trains with electric ones. If it were me, I'd be looking to replace Pacers with cascaded Sprinters, or perhaps in some cases with vehicles like PPMs.

 

[Pen Mill]

I dont think mileage is a particuarly useful figure, more important is how many services can be switched from diesel operation to electric - a big reduction in the need for DMU's can be achieved with a relatively small percentage increase in wiring.

Chris

I'm not sure about this.
Can you name lines which conform to this pattern ?

I don't believe a lot could be achieved in Scotland or Wales for example given the long distances involved.

One other interesting stat , although only 40% of lines are electrified , around 60% of journeys are on electrified lines , meaning that most of the suburban routes and in particular the London system are already done.

There are just over 1000 units in service at the moment

To make inroads into the above , major branch line OHLE would be required on the Northern network to reduce the number of Pacer diagrams.
The Cumbrian coast line will probably never be done.
158 , Cambrian coast , WestWales , Cardiff/Portsmouth,very unlikely
159, WEML , very unlikely.
165/168 , Chiltern Line , maybe but won't be included till Period 6 at the earliest.
A tumble cascade of 166/165/150/142 could get rid of pacers.
170 The majority of routes not on an agenda currently
171 Brighton-Ashford = no
172 Snow Hill line could be done
175 Required long term
180 Some could be redeployed with Oxford Elec.
185 Some could be redeployed with Lancashire Elec. and the Northern Hub eventually.

Is there really that much obvious obsolescence ? I don't think there's enough to say that diesel replacement couldn't happen.
The critical groups are the Sprinters and Networkers , can they be stretched for another 20 or 30 years ? that's a big hmmmm from me.

As far as I can tell, there's is little to no appetite for new diesel traction, nor for bi-mode trains. It was explained to me elsewhere on this forum that the R&D costs of a bi-mode would likely far outweigh the benefits.

Bombardier already have 300+ dual-mode or bi-mode sets running in France , why would they need R&D apart from gauging issues ?

 

[junglejames]

Manchester Airport to Southport via Bolton:
Half and half with all performance critical sections under the wires.

Manchester Victoria to Wigan Wallgate / North Western via Bolton:
As above.

Manchester Piccadilly to Buxton:
Not pacers directly, but with the same result and using a diesel on the non-critical section of the route.

Liverpool Central to Preston:
Re-open the route to be a through service at 2tph extending from Liverpool onwards to Preston, a 3 coach EDMU design works well, passing loops can be provided, again, all time critical sections are electrified.

Liverpool Central to Southport via Borcough Curves:
Kick starting curves to re-open, augmenting a pacer operated service on part of the route.

Liverpool Central to Wigan Wallgate via Kirkby:
Again, a half hourly extension by re-instating through service and providing passing loops.

Newcastle to Middlesbrough:
Different kind of EDMU here, running off 1500V DC where Metro infrastructure is provided, 25kV AC where available, and diesel elsewhere, this would be a variation on a design that could be used for Merseyrail Electrics and South West Trains, with a small modification to the power electronics module for the DC pickup and pantograph arrangments.

Leeds to Carlisle:
Similar to MIA to Southport, non-critical sections on Diesel, roughly half and half by track mileage.

This enough suitable routes yet or do I need to start on SWT and Southernland, and add in the CH services that run on LUL infrastructure electrified (shortly) at 750V DC...?

None of them are long enough under the wires to warrant the extra cost/ complexity, and in fact half of them are services which dont operate right now. Youd need to be sure these new services were definitely going to run before deciding what stock to purchase for them.
However, as I did mention replacing the 185s with bi modes, then if anything else could be found that warranted bimodes, then you do have the possibility of adding these to the routes currently operated by the TPE fleet.

As for SWT. All i can think of are the Exeters, but thats a different type of bimode. Same for the rest of the Southern.