Hope Valley Capacity Scheme updates

[HSTEd]

How many long tunnels have signals capable of showing red aspects within?

Well the obvious example is the London Underground, at least before ATO came in.

 

[LowLevel]

Why does Totley tunnel have to have a six minute headway?

Is there some restriction on the tunnel that prevents signal blocks being inside it?

I don't think they're popular. Being sat on a 150 inside a tunnel with something broken down in front and the associated fumes building would be unpleasant. Totley Tunnel only has ventilation shafts at the Sheffield end.

 

[HSTEd]

I don't think they're popular. Being sat on a 150 inside a tunnel with something broken down in front and the associated fumes building would be unpleasant. Totley Tunnel only has ventilation shafts at the Sheffield end.

Well presumably a signalling solution could be devised to allow trains that are not broken down to rapidly reverse back out of the tunnel and stack end-to-end at the end from which they entered?

 

[edwin_m]

Well presumably a signalling solution could be devised to allow trains that are not broken down to rapidly reverse back out of the tunnel and stack end-to-end at the end from which they entered?

The problem is that by the time the crew have tried a few basic troubleshooting procedures and informed the signaler of the failure, then an absolute minimum of 10min has gone by and probably much longer, and there could be several trains stacked up block on block behind. All the ones behind would have to be backed out in reverse order before the one trapped in the tunnel could move out, and for westbound in Totley that might mean getting some trains out onto the main line. If the failure needed assistance in rear and the first train behind couldn't provide that then the delay to the failure would be even longer.

 

[HSTEd]

The problem is that by the time the crew have tried a few basic troubleshooting procedures and informed the signaler of the failure, then an absolute minimum of 10min has gone by and probably much longer, and there could be several trains stacked up block on block behind. All the ones behind would have to be backed out in reverse order before the one trapped in the tunnel could move out, and for westbound in Totley that might mean getting some trains out onto the main line. If the failure needed assistance in rear and the first train behind couldn't provide that then the delay to the failure would be even longer.

Well the obvious other solution is to spend the money to provide multiple crossovers in the tunnel and ensure only one train per direction is between any pair of crossovers at any one time.
Then BiDi signalling can be used to route trains around the failed one.

 

[eastwestdivide]

With a six minute headway through the tunnel, that's a theoretical 10 slots an hour each way. Even with 4 passenger (one more than now) and 2 freight (more than most hours now), that's still room to spare, surely?

 

[The Planner]

Well the obvious other solution is to spend the money to provide multiple crossovers in the tunnel and ensure only one train per direction is between any pair of crossovers at any one time.
Then BiDi signalling can be used to route trains around the failed one.

Read that again and think about how easy that would be to implement, let alone cost for what is effectively a mitigation measure for something going wrong. The railway is accused of gold plating as it is!

 

[Bald Rick]

With a six minute headway through the tunnel, that's a theoretical 10 slots an hour each way. Even with 4 passenger (one more than now) and 2 freight (more than most hours now), that's still room to spare, surely?

If all the trains travel at the same speed between Dore and Chinley

 

[HSTEd]

Read that again and think about how easy that would be to implement, let alone cost for what is effectively a mitigation measure for something going wrong. The railway is accused of gold plating as it is!

Yes, but the railway is apparently unwilling to do without this mitigation measure.

But the tunnel capacity issue is rather problematic and does have to be dealt with.

 

[Roast Veg]

How many long tunnels have signals capable of showing red aspects within? I know Kilsby does, Severn Tunnel doesn't, Disley doesn't (I believe it is a repeater/distant on the down main inside the tunnel), Standedge doesn't (again a repeater/distant on the down and on the up), Chipping Sodbury?

Is the Sevenoaks tunnel a long tunnel? Don't know if there are any restrictions for stock that isn't an EMU in there.

 

[yorksrob]

Is the Sevenoaks tunnel a long tunnel? Don't know if there are any restrictions for stock that isn't an EMU in there.

It is, and I believe it does have signals inside.

 

[Killingworth]

If all the trains travel at the same speed between Dore and Chinley

Exactly; they don't! Fast passenger, slow stopping passenger and very heavy and slow freight. We aren't talking same class trains like use Thameslink or the Underground. Totley Tunnel is 6,230-yard (3.5 mi; 5.7 km) long.

This picture illustrates the problem. This heavy stone train of about 30 wagons (can't remember exactly how many, it was 3 years ago) had had to stop at Grindleford because the preceeding long and slow cement train had been unable to clear Dore West Junction to pull across to go south through Dore and Bradway Tunnels. That tight and up hill chord is limited to 10mph.

This train had to restart on the up hill grade into the tunnel and that isn't quick. Waiting behind it to clear was an East Midlands Liverpool - Norwich. Once one train is delayed a lot more delays knock on.

When the new tracks are completed I'm sure signallers will have just as much fun as now juggling all the new commutations!

 

[WestRiding]

Well the obvious other solution is to spend the money to provide multiple crossovers in the tunnel and ensure only one train per direction is between any pair of crossovers at any one time.
Then BiDi signalling can be used to route trains around the failed one.

Crossovers in the tunnel. Well that would be fun when they fail or just need maintenance, getting staff into the tunnel between trains, and no mobile phone signal. Anyway, back to reality.....

 

[HSTEd]

Crossovers in the tunnel. Well that would be fun when they fail or just need maintenance, getting staff into the tunnel between trains, and no mobile phone signal. Anyway, back to reality.....

The reality is that the railway will just have to accept the risk of fumes building up in the tunnel in that case.
There are no other tenable solutions, beyond closing the line or denying the freight trains.

 

[edwin_m]

Crossovers in the tunnel. Well that would be fun when they fail or just need maintenance, getting staff into the tunnel between trains, and no mobile phone signal. Anyway, back to reality.....

And in a dark wet tunnel on a gradient failure is much more likely, which would cause exactly the train-trapped situation they were supposed to avoid .

The reality is that the railway will just have to accept the risk of fumes building up in the tunnel in that case.
There are no other tenable solutions, beyond closing the line or denying the freight trains.

Another post from the Elon Musk of this forum. Lots of bright ideas but many of them totally impractical.

I rather think a "solution" that leads to people being poisoned falls into the latter category.

 

[HSTEd]

I rather think a "solution" that leads to people being poisoned falls into the latter category.

"We are stuck here until the train in front moves"
"We could you know.... turn the engines off?"
"No, they must continue to run at all costs!"

It's literally a plotline of Atlas Shrugged!

The railway exists to perform transport functions, it has to realise that it has no god given right to exist or consume billions every year in public subsidy.
It is rapidly being left behind by advances in other areas.

The limited headway through the tunnel is simply unacceptable, there is little point expending more money on this line if it cannot be remedied.

 

[edwin_m]

"We are stuck here until the train in front moves"
"We could you know.... turn the engines off?"
"No, they must continue to run at all costs!"

It's literally a plotline of Atlas Shrugged!

The railway exists to perform transport functions, it has to realise that it has no god given right to exist or consume billions every year in public subsidy.
It is rapidly being left behind by advances in other areas.

The limited headway through the tunnel is simply unacceptable, there is little point expending more money on this line if it cannot be remedied.

Crumbs, a combination of Elon Musk and Ayn Rand...

Your post...

The reality is that the railway will just have to accept the risk of fumes building up in the tunnel in that case.

...rather suggests that you favour leaving the engines on rather than turning them off.

 

[jfowkes]

All this suggests that the Hope Valley is a strong candidate for being wired (not that it wasn't already) - no fumes in tunnels, better train performance, higher reliability.

Anyone know if the capacity scheme has any passive electrification provision built in? I'm guessing not.

 

[zwk500]

The railway exists to perform transport functions, it has to realise that it has no god given right to exist or consume billions every year in public subsidy.

Well the obvious other solution is to spend the money to provide multiple crossovers in the tunnel and ensure only one train per direction is between any pair of crossovers at any one time.
Then BiDi signalling can be used to route trains around the failed one.

These 2 statements do not align.
The obvious solution to increase capacity in the tunnel if stopping is inadvisable (it is) would be to put a Signal in that cannot display a Red Aspect (aka Repeater or Distant signal). If a train is still in the tunnel or stood at Dore West waiting to cross, the following train will be held outside. If it's just following a train into sheffield the Aspect sequence would still be G-(YY)-Y-R. You don't quite get as much benefit as you would from a Red Aspect signal, but you get most of the way there

 

[HSTEd]

Crumbs, a combination of Elon Musk and Ayn Rand...

I in no way support Ayn Rand.
Just pointing out it was one of the utterly absurd polemics that Ayn Rand used!

...rather suggests that you favour leaving the engines on rather than turning them off.

In the case that the engines are left running whilst sitting behind a failed train.
The engines shouldn't be left running, but there we are.

 

[mwmbwls]

Totley Tunnel closed for safety reasons (04/03)

https://www.matlockmercury.co.uk/news/rail-passengers-face-disruption-after-historic-peak-district-tunnel-has-had-to-be-closed-1-9046617 Trains across Derbyshire are being disrupted after Totley tunnel at Grindleford has had to be closed for safety reasons during bad weather conditions. National...

www.railforums.co.uk

We discussed winter conditions in Totley Tunnel in 2018.

 

[InOban]

Don't modern locos have air-conditioned cabs with filtered air?

 

[Killingworth]

All this suggests that the Hope Valley is a strong candidate for being wired (not that it wasn't already) - no fumes in tunnels, better train performance, higher reliability.

Anyone know if the capacity scheme has any passive electrification provision built in? I'm guessing not.

It has.

Totley Tunnel closed for safety reasons (04/03)

https://www.matlockmercury.co.uk/news/rail-passengers-face-disruption-after-historic-peak-district-tunnel-has-had-to-be-closed-1-9046617 Trains across Derbyshire are being disrupted after Totley tunnel at Grindleford has had to be closed for safety reasons during bad weather conditions. National...

www.railforums.co.uk

We discussed winter conditions in Totley Tunnel in 2018.

It's very wet. Icicles! Steam trains would crash through them. They crash through modern windscreens.

 

[zwk500]

Don't modern locos have air-conditioned cabs with filtered air?

Air quality in the event of a stranded train is not the only reason not to stop a train in a tunnel if you can avoid it. Evacuation, communication, passenger experience (better to sit in a platform than the dark), access to train are among others.

The engines shouldn't be left running, but there we are.

Hoping the train in front can be rescued before the batteries go flat is not an ideal situation. We've had other discussions on these forums about situations where once the load-shedding begins the passengers decide fairly quickly to take matters into their own hands. I can imagine no worse place for an uncontrolled evacuation to happen than a 1+mile tunnel, except a 1+mile tunnel with 3rd rail.

 

[jfowkes]

It has

Woo forward thinking!

 

[30907]

It is, and I believe it does have signals inside.

As do Polhill and Penge tunnels. Not that they have or had vast numbers of heavy freights.

 

[zwk500]

As do Polhill and Penge tunnels. Not that they have or had vast numbers of heavy freights.

Similarly the Quarry line tunnel at Merstham has a signal inside, but 99% of traffic is EMUs, and no regular freight at all.

 

[yorksrob]

As do Polhill and Penge tunnels. Not that they have or had vast numbers of heavy freights.

They do have the odd thumper chugging through now and again though !

 

[Dr Hoo]

I thought that the various 'Southern' tunnels worked on a 'flying through' basis. I.e. that a train cannot be signalled into the tunnel unless the signal beyond the tunnels is showing a green aspect (so any train in the tunnel is very unlikely to slow or stop in or just beyond it).

The problem with Totley is that there are all sorts of reasons why trains will regularly stop just beyond the tunnel.

 

[WestRiding]

Where has all this come from about Stop signals in Totley tunnel? Its not going to be a thing.