Talerddig loop could be extended?

[richard_S]

Moderator note: Split from

Incident at Talerddig, Wales - 21/10/2024

Two trains have collided at Talerddig, Wales. Both trains are reported to be Class 158s running in 2 car sets. (Source, Realtime trains) At this time this is a developing situation and not all details are out in the open. The trains involved are believed to be: 1S71 Machynlleth to Shrewsbury...

www.railforums.co.uk

One solution to help this not happening again. Would be to extend the loop by 2-3 miles towards Caersws but leave the stop board towards Shrewsbury where it is and back up the stop board for trains to Machynlleth further back towards Shrewsbury.

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[Harpo]

One solution to help this not happening again. Would be to extend the loop by 2-3 miles towards Caersws but leave the stop board towards Shrewsbury where it is and back up the stop board for trains to Machynlleth further back towards Shrewsbury.

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And what of all the other loops on single line railways in the UK??

 

[richard_S]

And what of all the other loops on single line railways in the UK??

These could be looked at on a case by case basis. Lengthening if deemed to be unsafe due to leaf fall and wheel slip incidents.

 

[The Planner]

One solution to help this not happening again. Would be to extend the loop by 2-3 miles towards Caersws but leave the stop board towards Shrewsbury where it is and back up the stop board for trains to Machynlleth further back towards Shrewsbury.

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Massively expensive and unlikely when you can potentially timetable a solution.

 

[takethegame]

Massively expensive and unlikely when you can potentially timetable a solution.

Were these lines ever double in the first place?

Getting rid of singled tracks (i.e. redoubling) would be great if money was no object, however it wouldn't have helped in the Salisbury incident as that was on double track and IIRC due to poor adhesion and the driver leaving it late to apply the brakes?

 

[ChiefPlanner]

Massively expensive and unlikely when you can potentially timetable a solution.

Even if it could be funded (which I very much doubt) , the requirement for planning consents would take some years before the challenging civil works could start......

As you say , timetabling solutions are the answer..........

PS - the original Cambrin Railways was a pretty poor railway - for a 300 route mile system they had something like 100 locomotives to cater for a pretty thin traffic base from a lightly populated (and declining at that) , badly affected by lack of industry and a lengthy Victorian agrarian recession. Double track could not be afforded , though there were sections of it ......

 

[Unixman]

Massively expensive and unlikely when you can potentially timetable a solution.

Indeed. If, and only if, you were to do that, which I agree is highly unlikely, then you might as well move the loop to Carno and reopen the station.

 

[AndrewE]

Even if it could be funded (which I very much doubt) , the requirement for planning consents would take some years before the challenging civil works could start......

In post 114 we see a siding parallel to the line, so the loop could be that length at least. Maybe no need for "challenging civil works," certainly no planning consent needed to lengthen a loop on land already owned by the railway... Widening the notoriously deep cutting would not be an easy option though!

The Up Refuge Siding (to give the run-off siding its proper name) would only be relevant as an overrun if the trains were crossing under left-hand running; in this case, the trains were planned, and signalled, to cross under right-hand running.

The Down train (1J25 to Aberystwyth) was booked to stop at Talerddig from 19:24½ to 19:27½, while the Up train (1S71 to Shrewsbury) was booked to stop at Talerddig from 19:25½ to 19:26½. The Timetable Planning Rules explicitly state that "The first train into Talerddig MUST use the up loop."

Except that if you have rearranged the lines in the area and lengthened the loop that instruction would probably need revising, taking into account which way is downhill.

timetabling solutions are the answer.

as long as you don't want a better service.

 

[ChiefPlanner]

In post 114 we see a siding parallel to the line, so the loop could be that length at least. Maybe no need for "challenging civil works," certainly no planning consent needed to lengthen a loop on land already owned by the railway... Widening the notoriously deep cutting would not be an easy option though!

Except that if you have rearranged the lines in the area and lengthened the loop that instruction would probably need revising, taking into account which way is downhill.

as long as you don't want a better service.

Leafall periodic timetables have been implented for some years , just a thought. It would require considerable planning though to be fair.......and may not be easy.

I believe Talerddig cutting had some gold discovered when it was being excavated......this may be a non urban myth of course........

 

[Tomos y Tanc]

Massively expensive and unlikely when you can potentially timetable a solution.

An alternative in the longer term would be to replace Talerddig as part of the proposed re-opening of Carno Station where the formation is already double tracked. The local Rail Users Group has been making this argument for some time.

 

[Lurcheroo]

An alternative in the longer term would be to replace Talerddig as part of the proposed re-opening of Carno Station where the formation is already double tracked. The local Rail Users Group has been making this argument for some time.

The section through Carno station is single line, unless you mean there was once double track there ?

It is also on a falling gradient for Up trains and right on an AHBC.

 

[Bald Rick]

One solution to help this not happening again. Would be to extend the loop by 2-3 miles towards Caersws but leave the stop board towards Shrewsbury where it is and back up the stop board for trains to Machynlleth further back towards Shrewsbury.

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!!

Massively expensive and unlikely when you can potentially timetable a solution.

Or have much better sanding systems on trains, that cover all eventualities of low adhesion, from all causes, on the whole network, and not just in one place.

It will be interestign to see how the Variable Rate Sanders get on this autumn, and the extent to which money can be found for widespread fitment on other fleets that are susceptible to low adhesion.

 

[bahnause]

Or have much better sanding systems on trains, that cover all eventualities of low adhesion, from all causes, on the whole network, and not just in one place.

Or longer trains...

 

[30907]

Or longer trains...

Please explain

Apparently the two trains between them carried 40 passengers which is less than 15% loading. What length would be appropriate?

 

[Tomos y Tanc]

The section through Carno station is single line, unless you mean there was once double track there ?

It is also on a falling gradient for Up trains and right on an AHBC.

I mean it was double track and the formation still exists. Here's the case from the Rail User Group.
https://www.carnostation.org.uk/

 

[35B]

Please explain

Apparently the two trains between them carried 40 passengers which is less than 15% loading. What length would be appropriate?

If we ignore economics (arguably why this particular railway was built or still exists), the answer to your question is in the Salisbury Tunnel RAIB report. The braking performance of a single class 158 set is not as good as that of a longer formation. The argument therefore goes that it may be that, had 1J25 been formed of a pair of 158s, the braking performance would have been less impaired and the incident and it's outcome less serious.

 

[bahnause]

Please explain

Apparently the two trains between them carried 40 passengers which is less than 15% loading. What length would be appropriate?

The adhesion improves with each axle travelling across the track.

 

[Tomos y Tanc]

Please explain

Apparently the two trains between them carried 40 passengers which is less than 15% loading. What length would be appropriate?

Other services on this line have better loadings, but that's not the point. This is a vital link in a thinly populated area with appalling road connections. The railway serves an important social purpose.

 

[slowroad]

Other services on this line have better loadings, but that's not the point. This is a vital link in a thinly populated area with appalling road connections. The railway serves an important social purpose.

What is the social purpose that could not be met more efficiently and effectively by electric buses?

 

[JD2168]

Leafall periodic timetables have been implented for some years , just a thought. It would require considerable planning though to be fair.......and may not be easy.

The Sheffield to Huddersfield service has often had a different timetable in leaf fall season so this is possible.

My thoughts go to the family of the passenger who has died.

 

[stuu]

What is the social purpose that could not be met more efficiently and effectively by electric buses?

The roads are appalling. Rail journeys are far quicker between the major towns.

 

[Starmill]

Tram brakes and do indeed usually have to be specified with a maximum resistive force, because if the force were any higher it would be very risky for people onboard who may be unable to hold on tightly enough to resist being thrown to the floor by the stop. They are normally specified with a much, much lower mass per axle than a train, though.

Unfortunately there have been news reports of minor injuries onboard from trams using emergency braking in the past so it's something tram operators have to be congisant of in their safety cases.

 

[Llanigraham]

What is the social purpose that could not be met more efficiently and effectively by electric buses?

In a mountainous area of Wales, with poor roads that wind in and out of narrow valleys?
A bus between Machynlleth and Newtown would take probably 50% longer than the train and at some times of the day would probably not provide enough seats.

 

[The Planner]

An alternative in the longer term would be to replace Talerddig as part of the proposed re-opening of Carno Station where the formation is already double tracked. The local Rail Users Group has been making this argument for some time.

Carno is never going to wash its face with what's needed to make it work.

 

[30907]

Other services on this line have better loadings, but that's not the point. This is a vital link in a thinly populated area with appalling road connections. The railway serves an important social purpose.

Yes but what is your point? Should they be 4+ cars for greater safety, or remain as is?

I mean it was double track and the formation still exists. Here's the case from the Rail User Group.
https://www.carnostation.org.uk/

How would moving the crossing point as suggested reduce the risk of a SPAD?

 

[43096]

Or have much better sanding systems on trains, that cover all eventualities of low adhesion, from all causes, on the whole network, and not just in one place.

And cut the trees down.

It will be interesting to see how the Variable Rate Sanders get on this autumn, and the extent to which money can be found for widespread fitment on other fleets that are susceptible to low adhesion.

Agreed. Suspect this is being watched with even greater interest now!

 

[bahnause]

And cut the trees down.

That only works in places, where trees are the actual problems and cutting them down would not cause other negative effects. Other solutions like sanders might be eliminating other causes like industrial pollution.

 

[43096]

That only works in places, where trees are the actual problems and cutting them down would not cause other negative effects. Other solutions like sanders might be eliminating other causes like industrial pollution.

Hence why I said “And”.

Leaves are the biggest issue, though, and should be tackled course. There needs to be less pandering to the green lobby: it is a safety issue that, as we have seen this week, has the potential to kill people. That consideration far outweighs the tree-hugging.

 

[Annetts key]

How long is the existing double track (loop) section and whereabouts are any stations?
Only if the existing double track section is significantly longer than the length of the existing trains that use the line, moving the block marker boards (with appropriate changes to the signalling system) may be a more practical possibility.

 

[Lurcheroo]

How long is the existing double track (loop) section and whereabouts are any stations?
Only if the existing double track section is significantly longer than the length of the existing trains that use the line, moving the block marker boards (with appropriate changes to the signalling system) may be a more practical possibility.

The up loop (the actual loop bit) has a clearance of 175m in the down direction and 181m in the Up direction.

The down loop (the higher speed main line bit) is 176m in the down and 181m in the up. A 6 car set oh both 158’s and 197’s can easily be accommodated with the 197’s coming in at just over 144m for 6 coaches.