West Highland why only 156's?

[delt1c]

I seem to recall reading an article several years ago as to why 158's are not used on the West Highland service, cant recall the full reason but I think it was something to do with sliding doors instead of plug. Can anybody shed any light on the reason , there must be a good reason as the Fortwilliam / Mallaig and Oban services would be ideal candidates for 158's or 170's.

 

[laseandre]

It's because the clearances around the line are so narrow or something. 158s and 170s haven't been tested up there.

 

[91101]

I'd rather have a 156 anyway, the Haymarket based 158's are not the nicest of trains.

 

[driver9000]

Correct, class 158s arent permitted to run on the WHL. might be something to do with the swing plug doors and the foot boards under the passenger doors. Im not familiar with the WHL though I mentioned the doors because they have caused restrictions on 158s previously

 

[me123]

I'm sure it is also, as laseandre said, to do with the curves. there's a few tight curves that 158s and 170s would be unable to go round. Dunno what's going to happen when the 156s die, though... *prays for MkIIIs*

 

[driver9000]

Both 156 & 158 vehicles are 23m and are C3 gauge - I cant offer any other suggestions not being familiar with the line

 

[Donny Dave]

I don't see why the tight curves should rule out 158s, as they are shorter and slimmer than 156s.

Each carriage in a 156 is 23.03m long and 2.73m wide, compared to 158s being 22.16m long and 2.70m wide (figures taken from a platform 5 coaching stock book).

However, I've no idea of the speed limits along the WHL so I'm presuming this is a factor when Scotrail decide what units to run along there.

 

[Ascot]

Snows alot up the West Highland line and 158s have to slow down by 10mph every few mins. Only reason i can think of, and also it's easy for crews just to run one type train up and down the line which they have done since before the 90s. ScotRail also fit permanent RETB boxes (type of signalling on the line) to some of their 156s so it makes sense to stick to one batch of trains.

 

[laseandre]

I think the max. speed is 75, but thats on the North Clyde section anyway, so it'll be about 60 tops up North.

 

[Donny Dave]

Then again, all ScR 158s are RETB fitted anyway, so that isn't really an argument.

Mark, it also snows a lot on the FNL which is all 158s, so that argument can't be used either.

 

[Techniquest]

156s are also geared, if memory serves, for faster accleration than 158s. Which has just got to be useful for storming up gradients.

 

[Ascot]

Then again, all ScR 158s are RETB fitted anyway, so that isn't really an argument.

Mark, it also snows a lot on the FNL which is all 158s, so that argument can't be used either.

Wasn't an argument, was a suggestion so please don't put words in my mouth

Could also have something to do with 158s at Inverness and 156s at Corkerhill which uses services to Stranraer.

 

[Bayum]

Wasn't an argument, was a suggestion so please don't put words in my mouth

Could also have something to do with 158s at Inverness and 156s at Corkerhill which uses services to Stranraer.

I've heard somewhere before that the 158's have to slow down every so often when it's snowing... But I think I remember reading somewhere about it, but I honestly can't remember where...

Why is it??

 

[Ascot]

Due to experience of Class 158 DMU's braking characteristics, during freezing or snow conditions the following
instructions MUST be rigidly adhered to.

1.Running Brake Test

The brake must be tested every 2 minutes in the following circumstances:-
a)during freezing conditions
b)when snow is falling
c)when fallen snow is being disturbed by winds or by passing trains.

When this running brake test is made, the driver must make a Step 3 FULL SERVICE BRAKE application with a
10 MPH reduction in speed.

 

[Donny Dave]

That's to do with the brakes on a 158. In snow or icy conditions, the driver has do to a full service application every 10 minutes to drop 10mph to ensure ice doesn't build up on the brakes. I'm not sure if other units/locos have to do the same though.

Edit :: I thought it was every 10 minutes, but Mark posted at the same time as me and proved me wrong.

 

[driver9000]

Disc braked trains have to run at 10mph below the permitted speed and make a full service brake application every 3-5mins and retardation must be by 10mph. Trains do not have to be reduced below 50mph.

All trains must do the running brake test regardless of the type of brake.

 

[P156KWJ]

Correct, class 158s arent permitted to run on the WHL. might be something to do with the swing plug doors and the foot boards under the passenger doors. Im not familiar with the WHL though I mentioned the doors because they have caused restrictions on 158s previously

yeah there's a lot of specific platform bans on them as well, I think that 2 platforms at Hull are banned, and Platform 2C (the west facing bay) is banned from 158s too

 

[Max]

yeah there's a lot of specific platform bans on them as well, I think that 2 platforms at Hull are banned, and Platform 2C (the west facing bay) is banned from 158s too

As far as I know, 158s are not banned on any platforms at Hull, they regularly work into all platforms. Interestingly, 185s are banned from the last few metres of platform 2, but I believe this is a weight issue.

 

[Bayum]

Why are these trains banned?? I read about the doors that you mentioned, but I still don't know why...

 

[me123]

They're also banned entirely from Platform 4 at Glasgow Central. Not sure why, but I do know there's a lot of cant on that platform. 158s and 170s were prohibited, but are now cleared so which is odd though :? It's also banned from the bay platforms at Barrhead and Kilmarnock for some reason, although they'd never ever use them. Could be weight restricitons here too.

Anyway, back on topic, 158s in Scotland are severely restricted at platforms: eg they can't open their doors at Coatbridge Central. Could this be the/part of the reason for the ban?

 

[Doorslammer]

Let's face it, I'd rather trust the ploughs on a 156 than on a 158. Could that be a factor? (158 only has those protectors attached to the bogie if I recall correctly?)

 

[Ascot]

This'll be interesting with the snow up Scotland today. Check live departure boards on the 11:56 from Wick when it's about 2ish see how delayed it gets (that's if it's been snowing in that part).

 

[me123]

Sorry to disappoint, Mark, but the snow's already dissolved around here And I can't see any news that snow or adverse weather is causing problems.

 

[Ascot]

Sorry to disappoint, Mark, but the snow's already dissolved around here And I can't see any news that snow or adverse weather is causing problems.

Aw Obviously not Birmingham snow where everything shuts

 

[rail-britain]

From memory, wasn't the original Class 156 HA fleet modified for specific use on the WHL, in the same way as the Class 37/0 ED and 37/4 ED locos were, with additional wheel lubricating equipment

Does this not still apply to the Class 156 CK fleet, where only specific units can be used as these still carry that equipment

 

[me123]

Yup! There's a pool of 15 FSR (non-SPT) units fitted with RETB. See here. In reality, only about 7 of these are in use on a daily basis, so the rest to et around the network! Other than the WHL diagrams, all the units are in the same pool so any train can end up anywhere, provided that the 7 or so WHL diagrams are served by RETB trains.

I'm not sure if there's any other modifications, though.

 

[Doorslammer]

Of course, RETB. *slaps own face* A very specific requirement on that line...

Hindsight, eh?

 

[me123]

Well, 158s are RETB fitted considering they are used on Far North and Kyle of Lochalsh lines (and I think on parts of the Aberdeen-Inverness line).

 

[rail-britain]

I'm not sure if there's any other modifications, though.

I'll try and find some photos of the additional equipment the locos and units have

There's a brief mention on http://members.madasafish.com/~dysgraphyk/156/class156_mods.htm

Wheel noise
When the class took over duties on the West Highland line in 1989 the flange squeal on tight curves caused a lot of discomfort to those on-board. This was solved late in the year by gluing an aluminium disc, about 5mm thick, to the web of the wheels. All wheelsets are now fitted in this way

There is no RETB between Aberdeen - Inverness

 

[P156KWJ]

Aw Obviously not Birmingham snow where everything shuts

even birmingham Snow Hill?