Great Western Coffee Shop

I think that the whole country incuding the South West of England need more Sprinter Trains. The ones that work at the moment are not very efficient and train making companies should invest in new cheap trains like Sprinters. What I mean by that is that the trains will have the same design (interior/exterior) as the normal sprinters/super sprinters (class 150 - 158) as well as having more coaches (from 2 coaches to 3/4 coaches - centre cars).

Noooooooooo!

The last thing you need on stopping train services is great big diesel engines sucking great gobbits of fuel just to move you from Nailsea to Yatton about 25 seconds quicker. As far as the current 15x is concerned the mechanical parts are about as reliable as it gets and the reasonably light vehicle weight suits the 285 - 350 bhp engines just nicely. You could possibly go the common rail engine route on them much the same as has been done with the HST fleet but upping the power much above what they are to some stupid figure makes no sense at all. Kindly note what TPEx are doing with eco mods in order to tame the 185's legendary ability to waste fuel if driven 'enthusiastically'. The last thing you need is some sort of clone of 185 on local plug runs.

You could possibly argue a case for something of about 500bhp / 45 tonnes per steel bodied car with aircon for the Cardiff - Portsmouth run but using high powered units on most of the other class two runs is an absolute and total no-brainer. All it does is up the fuel consumption at a time when oil prices are heading into orbit at a rapid rate. All of which the taxpayer or customer will have to stump up for.

As for the ROSCO's why invest in new diesel units when electrification of routes (which is really the way forward) will release mid life diesel units for other duties? If for example the LTV service area gets wired that could mean the most of the current LTV 16x looking for work. Good units provided the loading gauge issues can be overcome.

 Another point that should be noted is that providing they can be cleared for the routes  that what's to stop FGW or who next gets the franchise transfering some of the displaced class 165's down to the west country.

I don think that a small fleet of DMU's is required at least to replace the pacer units which have to be withdrawn by 2019, how about building some more class 172's and also wire the gospel oak - barking line and then transfer those class 172's down to bristol to work services to Severn beach and maybe a service via Henbury

Depends on the dft though.  For example once the 319s are cascaded they could decide to take the turbos away from FGW.

Thats true. Wouldnt be too surprised if the DFT did that, as long as they dont come to the valley line network i will be happy.

 Then again if a class 158 cant fit north of taffs well then what hope has a class 165

build more pacers would be cheaper.....enviro200's on rails.... i will get my coat

I agree on one point, we need more Sprinters. However, the reason I think that is: they are so much lighter (and therefore make maintaining the track cheaper) than most newer DMUs. Being so much lighter they are probably much more fuel efficient than the newer units too, which is good when we have climate change and peek oil to worry about. Therefore I disagree that they should be any more powerful, their low weight makes them accelerate pretty quickly anyway doesn't it (why else would they be called Sprinters)? Also, while I think we need more Sprinters, I think it's too late to build them now (because we don't really want to have many deisel trains left in 30-40 years time), ideally they should have been built back around the time of the 170s.

If new DMUs are to be built, then I feel that serious consideration should be given to hybrid drive (diesel/battery).
In order to give reasonable performance, a diesel train typicly needs from about 300 up to over 500 HP per vehicle.
This much power is required in order to give good acceleration and to ascend inclines at an aceptable speed.
The average power needed is much less, but the heavy and expensive engines need to be sized for the peak power required, not the average.

Instead, one could build a 4 car hybrid multiple unit with say 350HP engines under 2 coaches only, with electric transmission as on voyagers.
The other 2 vehicles would be fitted with traction motors of say 400HP short term rating and suitable batteries.

That would give 1,500 HP for a 4 car set and ensure ample acceleration. The electric motors would only be required when accelerrating away from stops and ascending gradients. The 700 HP from the diesels being sufficient to maintain line speed on level track, and leave a modest surplus for battery charging.
Whenever the train is stationery or coasting, allmost all the engine power would be available for battery charging.
When braking, regenerative braking would be easily achieved, saving fuel and brake wear.


Only 2 engines need be purchased and maintained, and these 2 engines would run for longer periods at their most efficient power output.

On routes with many stops and lower speeds it might be possible to shut down one engine, since a single engine would charge the batteries during the many stops.

Very interesting comments hybrid diesels not sure current battery technolgoy ie power to weight ratio would give much advantage.

There is a piece in Modern Railways this month re Bombardiers new TRAXX diesel loc. It is fitted with 4 Caterpillar automotive diesel engines which will start up as required. Thus idling and providing hotel power will use one engine and then when the train starts the other 3 will start and provide maximum power for acceleration then drop out when up to speed. Thus engines will work mostly at their optimum output.

Presuambly it requires quite complicated software to switch the engines on and off and rotate the idling engine to even out engine hours. Be interesting to see how it works in trials. Apparently it tries to do what the unsuccessful BR Fell prototype (1950's) did with mechnical gearboxes.

more chance of more Bulleid's Leader's

In London we now have a number of hybrid drive buses which is an encouraging sign.

Buses are of course lighter in weight than DMUs, and the technology is probably not directly transferable from buses to DMUs.
This does however show the potential of the idea.

There has been talk of adding a pantograph and transformer car to voyagers so as to permit of electric operation.
How about fitting  2 battery/motor coaches to a voyager.
That would give 2 much needed extra coaches of passenger space, with no loss of performance as the batteries would be used for acceleration and ascending inclines.
The batteries being charged when coasting, stopped, or proceeding at reduced power.

I am sure I read an article about Bombardier looking at flywheel technology as a means to improve the efficiency of dmu's and allow for greater acceleration.

realise its a demu but didnt the class 210 have quite good acceleration

Yes, we need a rolling order of 172s (or equivilent) to replace ALL stock pre the 158s (and then the 158s too). I've always said this.

Electrification is coming, but not in the next 30 years for some mainlines, let alone branches.

I wouldn't say that exactly. 172s with their suburban design are not really suitable replacments for classes 153 to 159. Hopefully electrification (directly or indirectly) will clear most if not all the Pacers off the network so that leaves an order of 75mph 172s (the London Midland version with corridor-fitted-cabs) to replace 150/0s and 150/1s (life-extend the other Sprinters in the hope electrification will proceed fast enough that most won't need diesel replacements). Life-extending the 153s is expected to entail converting them back into 155s so I would suggest an order of 172-based trains laid out like a class 175 (doors located in vestibles at the ends of vehicles, seats with legroom and aligned with windows ext. (but with padding, unlike 175 seats)) but with corridor-fitted-cabs like 158s/159s, 377s and LM-172s to boost the numbers to compensate. This would be a 90/100mph unit, perhaps including a pantograph car (creating a bi-mode, but with the lower top-speed and 23m vehciles this would be a far more useful one than the 125mph train with 26m vehicles DaFT are planning with IEP, since most (probably all) the 125mph lines will be electrified by 2020).

There's always these (http://www.locomotives-for-sale.com/uploads/sales-offer/1-18-2-30-1-Broad-Gauge-2-Car-DMU-For-Sale.pdf), if regauged. Though I suspect that FGW have probably had quite enough erratic 'Almost' DMUs for the time being.

The *look* like class 158 units ... and there are 27 of them.  That's sufficient to be a true standard fleet not an oddball setup.

But you have to ask why the Irish have got rid of them only half way into their designed life span, despite overhauling them in 2010.

From reading up on other forums (for what that's worth) there seems to be two reasons: 180-style reliability and IE's bizarre procurement policy. They're certainly not the units you'd choose if there were a rolling stock surplus. But there isn't, and I can think of several places these would be very handy - ATW, for one...

It's 27 cars. 12 two-car DMUs (Class 2700) an 2 single car units (2750). With one spare car to cover for faults/ maintenance, which is half of a Class 2700 2 car unit.

The spare was latterly added to the spare from the earlier Class 2600 2 car DMUs to form a 'hybrid' unit.

70mph 2-car units with a suburban-door layout. Sounds like a good replacment for Pacers but Wales' Pacers should be getting EMU replacments in the next 8 years. Maybe replacements for some of Northern's Pacers and/or some 150/1s.

Personally, I'm not so sure re-gauging these IE units would be that straightforward.

Are there off-the-shelf bogies that can be purchased? If not, then the expense of procuring a new build of bogie for a relatively small fleet may be prohibitive.

Then there's other hardware to take into account. Such as UK standard TPWS. What about the engines and traction motors? Will there be a ready supply of spare parts from Cummins and would those parts be interchangeable with existing parts for UK DMUs? And what of operational flexibility to run these IE units in multiple with existing UK stock? Couplers?

All probably not insurmountable issues, but I doubt it's just as simple as bolting on some 4ft 8^in bogies, and putting them into traffic.

Are Knorr brakes a stock item?

Ba-dummm, tschhhh.

Keep it up son, we'll soon have you playing the big venues.

Delighted to have those looked after with FGW territory  ;D

http://www.knorr-bremse.co.uk/en/group/kbingermany/kbingermany_group.jsp

I never cease to be amazed by how my knowledge can be increased by following these threads!  :)