Welsh fleet deployment programme rationalised

[Skip 10]

Ffrairfach IIRC is the issue, plus they're only allowed on one side of the loop at one of the passing places (I think llandovery). 158s would be ideal units for the HOWL in the long term, if those issues could be dealt with (and I see no reason why they couldn't) but until we hear otherwise, we must assume the plan is still for the line to get 170s eventually. I wouldn't worry too much about the issues with running 170s at low speeds - aside from the fact they get a decent enough dash back on the mainline at each end of the route (including a maximum of 90mph which should be achievable between Church Stretton and Shrewsbury northbound) they'll be mixed in with other services throughout West Wales and Crewe - Shrewsbury locals (where again 90mph should be just about achievable, albeit briefly).

Llanwrtyd has to be taken at extreme caution heading towards Llandrindod too. The step boards are very close to the platform edge as you swing out of the loop.

 

[Caaardiff]

The 170s aren't being fully utilised at the moment which seems a waste considering the current shortages. It would make sense to at least get them cleared to Swansea and run them on swan line stations that shuttle between Cardiff and Swansea and would likely avoid the need to train up Carmarthen train crew on them in the short term.

 

[edwin_m]

A 158 has similar transmission to a 170, albeit geared for a top speed 10mph less. Would it have the same issues with fuel consumption on the HoWL?

 

[PHILIPE]

The 170s aren't being fully utilised at the moment which seems a waste considering the current shortages. It would make sense to at least get them cleared to Swansea and run them on swan line stations that shuttle between Cardiff and Swansea and would likely avoid the need to train up Carmarthen train crew on them in the short term.

I think 170s are clear to Landore Jn but not into Swansea itself as there have been visits to the Depot there

 

[Bletchleyite]

A 158 has similar transmission to a 170, albeit geared for a top speed 10mph less. Would it have the same issues with fuel consumption on the HoWL?

Not so much. The issue with 170s is the gearing.

 

[craigybagel]

A 158 has similar transmission to a 170, albeit geared for a top speed 10mph less. Would it have the same issues with fuel consumption on the HoWL?

On 158s the transmission changes at around 54mph IIRC (it's hard to hear from the cab), and lower if the throttle is at a lower setting. On 170s it's about 67mph. The line speed on the majority of the HOWL is 55 or 60mph, so whilst 158s would be able to change gear, 170s wouldn't.

 

[Bletchleyite]

On 158s the transmission changes at around 54mph IIRC (it's hard to hear from the cab), and lower if the throttle is at a lower setting. On 170s it's about 67mph. The line speed on the majority of the HOWL is 55 or 60mph, so whilst 158s would be able to change gear, 170s wouldn't.

If it's this that's more the issue than the longer gearing, is it possible to reconfigure it? 170s are older kit so it's probably something physical that does it rather than software, but a mod might be possible? Given that 170s are now moving onto local stopping services across the UK, this would give a big fuel saving nationally.

 

[craigybagel]

If it's this that's more the issue than the longer gearing, is it possible to reconfigure it? 170s are older kit so it's probably something physical that does it rather than software, but a mod might be possible? Given that 170s are now moving onto local stopping services across the UK, this would give a big fuel saving nationally.

I'm a long way from being an expert on these things so I'm really not sure. I suspect the fact that it hasn't been done yet, despite similar issues being raised at London Midland and Northern makes me think it's either too hard or too expensive. And as I pointed out, it's not like the 170s will only work over the HOWL, so if they're suitable for most but not all of the routes they're working it's probably not such a big deal. They'll get plenty of chances to stretch their legs.

 

[hwl]

If it's this that's more the issue than the longer gearing, is it possible to reconfigure it? 170s are older kit so it's probably something physical that does it rather than software, but a mod might be possible? Given that 170s are now moving onto local stopping services across the UK, this would give a big fuel saving nationally.

Comparatively easy to do as you can change the final drive gears in the on the axle units rather than anything in the transmission itself, though that won't be completely optimal you might end you doing a few changes in main transmission as there are some fixed gear reduction and increase gears in there too.

 

[Bletchleyite]

Comparatively easy to do as you can change the final drive gears in the on the axle units rather than anything in the transmission itself, though that won't be completely optimal you might end you doing a few changes in main transmission as there are some fixed gear reduction and increase gears in there too.

Given where they're getting used, I could see the sense in regearing down to 75mph - you'd get a substantial acceleration gain, too (as things stand a 150 is substantially quicker off the mark). Same with the Northern ones used on the Yorkshire stopping services via Harrogate.

 

[Rhydgaled]

Ffrairfach IIRC is the issue, plus they're only allowed on one side of the loop at one of the passing places (I think llandovery). 158s would be ideal units for the HOWL in the long term, if those issues could be dealt with (and I see no reason why they couldn't)

Are both of these a problem with platforms as 'Skip 10' reports for Llanwrtyd and Llandrindod?

Llanwrtyd has to be taken at extreme caution heading towards Llandrindod too. The step boards are very close to the platform edge as you swing out of the loop.

Other places have reportedly had their platforms edges cut back a little to provide clearance for stock that couldn't previously operate, so presumably this isn't too difficult in the grand scheme of things. Would platform alterations alone be sufficient to solve this issues regarding 158s on the HOWL?

I wouldn't worry too much about the issues with running 170s at low speeds - aside from the fact they get a decent enough dash back on the mainline at each end of the route (including a maximum of 90mph which should be achievable between Church Stretton and Shrewsbury northbound) they'll be mixed in with other services throughout West Wales and Crewe - Shrewsbury locals (where again 90mph should be just about achievable, albeit briefly).

What exactly is the problem with 170s being used at low speeds, is it just that they like a small amount of fast running in their day or is a majority of slow running (which the HOWL would be with only a small section of the marches to get above 75mph) a problem for them?

I'm a long way from being an expert on these things so I'm really not sure. I suspect the fact that it hasn't been done yet, despite similar issues being raised at London Midland and Northern makes me think it's either too hard or too expensive. And as I pointed out, it's not like the 170s will only work over the HOWL, so if they're suitable for most but not all of the routes they're working it's probably not such a big deal. They'll get plenty of chances to stretch their legs.

On 158s the transmission changes at around 54mph IIRC (it's hard to hear from the cab), and lower if the throttle is at a lower setting. On 170s it's about 67mph. The line speed on the majority of the HOWL is 55 or 60mph, so whilst 158s would be able to change gear, 170s wouldn't.

Apart from Craven Arms - Shrewsbury (and on to Crewe if they extend the HOWL services through), they wouldn't see much fast running as far as I can tell. Cockett tunnel to just short of Ferryside (75mph) and from the west end of Carmarthen (lifting) bridge to Clarbeston Road (75mph with short stretches of 50-70mph Whitland) and one other short strech of 75mph north of Ferryside would allow them to get above 67mph I suppose, but there's nothing above 75mph west of Swansea.

Cardiff - Cheltenham seems to be pretty much an ideal route for the 170s, with a fair amount of 90mph linespeed AND it's a stopping service where the suburban door layout is useful AND it doesn't degrade the journey experience of long-distance passengers who are unlikely to use a local stopping train like this from end to end (although, lack of gangways aside, the TfW 170s would probably be a better choice for a long-distance service like Manchester-Swansea than the upcoming class 197 abominations).

Leaving the 170s on their current routes permanently would of course free up the units that are meant to be replacing them in a few years time, brand new Stadler DMUs. I think it's safe to say there's not a chance that those brand new units will go to West Wales and the HOWL whilst Cardiff keeps its much older 170s - so sooner or later the 170s will need clearing for other routes. The emphasis at the moment seems to be on later.

The proposed Stadler diesels have never made much sense to me; as noted above a 170 appears well suited to the Cardiff-Cheltenham service and the only reason I can see for wanting to use something else is the OHLE between Severn Tunnel Junction and Cardiff. Thus, bi-mode Stadlers I would understand, but where's the benefit of a pure diesel FLIRT over a 170? The Welsh Government has started murmuring about a Swansea Bay Metro; I wonder whether the Stadler diesels could be diverted for that (although electrification, either full or partial with bi-modes, of said metro would of course be preferable)?