Speed Limit & HST Question

[antharro]

At the SWT/Siemens traincare facility at Southampton are two speed limit signs mounted on the same pole. The top one says "80", the bottom one says "HST 85".

Why is the HST allowed to go faster, and when was the last time a set was down this way? I seem to recall something about only sets with short links (?) being allowed down this way, certainly only short link sets could go to Bournemouth.

I also heard that since privatisation, the information on which sets had short links and which didn't had been lost so there was no way of reliably running HSTs to Bournemouth... which doesn't seem at all right?

 

[richw]

the coaches coding on the ends dictate whether the carriage has short link or not,
I came across a similar sign the other day that had 2 speeds on, one for MUs and the other for LH i believe, see my attachment as i had never noticed it before in the location i was at, and suspect it to of been a new sign

 

[notadriver]

Allowed to go faster due to having superior braking and/or lighter axle loading.

 

[Kingfisher200262]

At the SWT/Siemens traincare facility at Southampton are two speed limit signs mounted on the same pole. The top one says "80", the bottom one says "HST 85".

Why is the HST allowed to go faster, and when was the last time a set was down this way? I seem to recall something about only sets with short links (?) being allowed down this way, certainly only short link sets could go to Bournemouth.

I also heard that since privatisation, the information on which sets had short links and which didn't had been lost so there was no way of reliably running HSTs to Bournemouth... which doesn't seem at all right?

I think over time, the ROSCOs have implemented a mod to convert all long swing links to short.

 

[Barrett M95]

It doesn't specifically mean an HST (class 43...) : it refers to things like 22X units too that also use this route. There are a number of unit types it can apply to. I don't have an exhaustive list but that's what it means anyway.

 

[IanXC]

Here is said list:

This is what the letters mean:

HST class 91 locomotive with mark 4 vehicles and DVT, 168/170/171/175/180/220/221/222/253/254/373/390
MU multiple unit trains
DMU diesel multiple units
EMU electric multiple units
SP class 150/153/155/156/158/159/165/166/168/170/171
CS class 67 locomotive

At locations where both HST and SP speeds apply, classes 168/170/171 may run at the higher of the two speeds.
Class 185 trains must not run at any MU or DMU speeds.

http://www.rgsonline.co.uk/Rule_Boo... and Speed Restrictions/GERT8000-SP Iss 3.pdf

 

[Schnellzug]

So Turbostars are HSTs?

 

[Kingfisher200262]

A naive question for all the drivers on here; how do you see the speed limit and other line side signs in the dark?

If the answer is that you don't need to see them because you know the route, what's the point of them being there?

 

[hairyhandedfool]

Trains have headlights

Drivers should know the route, but there is no harm in having reminders.

 

[Schnellzug]

I've always wondered hos they managed back in the Old Days, when a lot of steam locos didn't even have speedos, so surely there must have been an enormous amount of trial and error involved. (And a lot of erring-on-the-safe-side when it came to speed restricitons, I expect.)

 

[Kingfisher200262]

Trains have headlights

Drivers should know the route, but there is no harm in having reminders.

I've always thought that train headlights were so that a train could be seen, as much as the driver being able to see. This is why day headlights are specified brighter than light headlights.

See Appendix 3, HERE.

As I said in my first posting on this subject, it was a naive question and I would like to hear drivers' views on this.

 

[exile]

I've always wondered hos they managed back in the Old Days, when a lot of steam locos didn't even have speedos, so surely there must have been an enormous amount of trial and error involved. (And a lot of erring-on-the-safe-side when it came to speed restricitons, I expect.)

Not really trial and error. By the time a driver had qualified they'd have done the route as fireman, sometimes taking the controls under supervision, hundreds of times and would know it as well as you know your drive to work. The driver would be given a list of temporary speed restrictions if there were any.

 

[tom1649]

Class 185 trains must not run at any MU or DMU speeds.

I wondered if this would be the case. I've heard about 185s being heavier than other units. Are there many points where they are affected by this rule on the routes they serve? I think there may be at least one point on the Hope Valley where they are.

 

[hairyhandedfool]

I've always thought that train headlights were so that a train could be seen, as much as the driver being able to see. This is why day headlights are specified brighter than light headlights.

See Appendix 3, HERE.

As I said in my first posting on this subject, it was a naive question and I would like to hear drivers' views on this.

That is what they are there for, but the question was "how do drivers see the signs at night".

 

[GB]

I've always thought that train headlights were so that a train could be seen, as much as the driver being able to see. This is why day headlights are specified brighter than light headlights.

See Appendix 3, HERE.

As I said in my first posting on this subject, it was a naive question and I would like to hear drivers' views on this.

Its for both depending on the circumstance.

Most trains have two sets of headlights (not including marker lights) called day and night. The day headlight is positioned on the second mans side (6 foot side) to allow a better visual for anyone that is on or near the line.

The night headlight is positioned on the drivers side (cess side) to minimise dazzle to oncoming drivers and to illuminate lineside signs as well as for the benefit for anyone on or near the line.

 

[Kingfisher200262]

Its for both depending on the circumstance.

Most trains have two sets of headlights (not including marker lights) called day and night. The day headlight is positioned on the second mans side (6 foot side) to allow a better visual for anyone that is on or near the line.

The night headlight is positioned on the drivers side (cess side) to minimise dazzle to oncoming drivers and to illuminate lineside signs as well as for the benefit for anyone on or near the line.

So, how far ahead can you see at night and what is this in terms of time, at an approaching speed of, say 100 mph?

 

[driver9000]

The modern signage is reflective so the headlight shines off it at night. We know where the speed changes are anyway through route knowledge, plus the old cut out signs aren't reflective.

At night in clear visibility (no fog or heavy rain) the headlight on the trains I work illuminates maybe 60ft in front of the train at track level. The light doesn't shine far although the newer halogen lights are brighter so light up a bit further. Once your eyes have adjusted to the dark its easier to pick things out and its rarely 100% black. Driving in thick fog can result in near 0 visibility, route knowledge comes into its own in those conditions.

 

[JoeGJ1984]

I presume that on richw's picture, the letters on the sign say MU and not ML as I thought? (Because ML isn't in the list).

Sometimes you get two speed limits with no letters on any of them. What do they mean?

 

[driver9000]

Sometimes you get two speed limits with no letters on any of them. What do they mean?

On a differential sign with no letters passenger, parcels and light locos can obey the higher speed value.

 

[swt_passenger]

I also heard that since privatisation, the information on which sets had short links and which didn't had been lost so there was no way of reliably running HSTs to Bournemouth... which doesn't seem at all right?

The information isn't actually lost, but some sets were formed of both types, and even if some carriage end markings are wrong, the info is held elsewhere anyway.

How else would FGW have been able to run between Basingstoke and Waterloo if they didn't know?

AIUI XC have no SSL sets, so can't run their own HSTs to Bourenmouth, but FGW wouldn't have an isssue if asked.

 

[shedman]

There is stickers on the ends of the HST mk3 coaches next to the data panels saying SSL, I'm sure there is LSL too but can't remember

 

[TEW]

Around the time of the Waterloo diversions lots of FGW HST coaches had evidence that the SSL/LSL markings on the ends of coaches had been altered. I believe at some time they had all been marked as LSL, but they should now be correct.

 

[richw]

I presume that on richw's picture, the letters on the sign say MU and not ML as I thought? (Because ML isn't in the list).

Sometimes you get two speed limits with no letters on any of them. What do they mean?

Yes it does say MU, the sign is recently erected or i'd fail to notice previously,we never get anything except 150s and 153s down here though, unless there is a special due at some point soon!

 

[notadriver]

Drivers must pass a route exam before being allowed to drive unsupervised on that route.

 

[starrymarkb]

I think over time, the ROSCOs have implemented a mod to convert all long swing links to short.

Not as far as I'm aware. There were some very strange formations running on FGW during the Reading blockade. Westcountry services had to be all SSL to run into Waterloo

 

[Kingfisher200262]

Not as far as I'm aware. There were some very strange formations running on FGW during the Reading blockade. Westcountry services had to be all SSL to run into Waterloo

I'm a bit surprised by that. It's such an easy mod and given that the whole fleet went through Litchurch Lane four or five years ago, when presumably all the bogies were overhauled, I would have expected it to have been specified during the overhaul.

 

[TDK]

So Turbostars are HSTs?

No, Turbostars are turbostars allowed to run at HST speeds
--- old post above --- --- new post below ---

A naive question for all the drivers on here; how do you see the speed limit and other line side signs in the dark?

If the answer is that you don't need to see them because you know the route, what's the point of them being there?

I personally do not need to see the speed signs on the routes I sign as I know where the speeds are however, many freight drivers and also if you are diverted onto a route you do not drive over on a daily basis the speed signs especially the warning of a speed reduction sign can be of help reminding the driver "exactly" the location of a speed reduction/increase. As for seeing the speed boards at night you can see them as they are retro reflective. If there is a speed decrease of more than 30% you will always have a warning board with associated AWS so as not to miss the speed, some speed restrictions also have TPWS OSS associated with them, so there is no worry of an unsafe scenario at night or in thick fog etc. if a driver makes an error in their location (this happens very rarely if at all)

 

[antharro]

Thanks for the comprehensive replies!

Question - although I know there are short swing links and long swing links... what are they? Something to do with the couplings between carriages? Or something else entirely?

 

[Mainliner]

Thanks for the comprehensive replies!

Question - although I know there are short swing links and long swing links... what are they? Something to do with the couplings between carriages? Or something else entirely?

http://rail.bodnet.com/oddments/llsl.html

 

[142094]

There are also some signs for certain types of wagom, Yarm viaduct has a restriction for HAA hoppers; the sign has a picture of the hopper and the lower speed.