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London trains see power cut as thousands stranded in dark for hours

metro.co.uk

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Re: London trains see power cut as thousands stranded in dark for hours

#71

Post by corobo »

NoMoreNicksLeft wrote: post #63
yabones wrote: post #17

Earlier quoted context omitted.

The old-style "tube" trains are all DC third rail IIRC, but the newer trainsets such as the Elizabeth and Thameslink are all overhead AC. So this would actually be one of the few metro trains where it would be remotely safe to walk the tracks provided all the trains were stopped...

If not all trains are stopped, aren't they in danger of collision if they remain on the train?

I'd really hope that modern signalling prevents trains entering signal blocks with other trains in (or can't confirm there's no train in) them.

As in actively prevents, locking the brakes at the previous block, rather than allowing drivers to miss or ignore signals.

We've had plenty of issues with this to learn from in the history of railways for it not to be a high priority.

E: aye seems that way :)

> In order to prevent a train from entering an occupied block, each signal has a mechanical ‘trainstop’ next to the track. This device applies the brakes of any train which tries to pass a stop signal.

https://madeby.tfl.gov.uk/2019/07/24/behind-the-scenes-signa...

Re: London trains see power cut as thousands stranded in dark for hours

#72

Post by tristramb »

rsynnott wrote: post #12
michaelt wrote: post #2

> Some frustrated travellers even smashed their way out the cold, dark trains and walked down the tracks to escape after getting stuck for more than three hours. It's a shame train operators don't feel able to make the common sense decision to give the passengers the option to walk before the three hour mark, without requiring them to "smash their way out". Obviously, some passengers won't be able to make the trek, a…

London trains are mostly third rail powered rather than overhead line, right? You really don't want people walking on one of those. Like, you don't want people walking on any train line, but particularly not one with a third rail.

It s probably also illegal. They could prosecute you for trespassing on the rail way if you are not supervised.

I used to commute into London before Covid and there were times when we were delayed so long that I thought we might have to resort to cannibalism.

Re: London trains see power cut as thousands stranded in dark for hours

#73

Post by bobthepanda »

corobo wrote: post #71
NoMoreNicksLeft wrote: post #63

Earlier quoted context omitted.

If not all trains are stopped, aren't they in danger of collision if they remain on the train?

I'd really hope that modern signalling prevents trains entering signal blocks with other trains in (or can't confirm there's no train in) them. As in actively prevents, locking the brakes at the previous block, rather than allowing drivers to miss or ignore signals. We've had plenty of issues with this to learn from in the history of railways for it not to be a high priority. E: aye seems that way :) > In order to pr…

The issue is during evacuation, people may not have the sense to stick to the track their train is stuck on, and may spread out into a parallel track.

Re: London trains see power cut as thousands stranded in dark for hours

#74

Post by kevincox »

corobo wrote: post #71
NoMoreNicksLeft wrote: post #63

Earlier quoted context omitted.

If not all trains are stopped, aren't they in danger of collision if they remain on the train?

I'd really hope that modern signalling prevents trains entering signal blocks with other trains in (or can't confirm there's no train in) them. As in actively prevents, locking the brakes at the previous block, rather than allowing drivers to miss or ignore signals. We've had plenty of issues with this to learn from in the history of railways for it not to be a high priority. E: aye seems that way :) > In order to pr…

The walking passengers may enter a block that their train has already cleared. So you can't really assume that wherever they walk will be locked.

Re: London trains see power cut as thousands stranded in dark for hours

#75

Post by bobthepanda »

hedora wrote: post #69
Symbiote wrote: post #57

Earlier quoted context omitted.

Britain obviously wouldn't build a new tunnel without an evacuation route, but the existing tunnels can be 100 or more years old and lack them.

That's exactly why I read the article! I wanted to see the statement from the train company explaining how they're fixing that!

There isn’t really a way short of fixing this short of building brand new replacement tunnels at great expense.

You can’t really widen the tunnels, because the tunnel lining itself is the structure preventing water seepage, cave-in, etc.

Re: London trains see power cut as thousands stranded in dark for hours

#76

Post by corobo »

bobthepanda wrote: post #73
corobo wrote: post #71

Earlier quoted context omitted.

I'd really hope that modern signalling prevents trains entering signal blocks with other trains in (or can't confirm there's no train in) them. As in actively prevents, locking the brakes at the previous block, rather than allowing drivers to miss or ignore signals. We've had plenty of issues with this to learn from in the history of railways for it not to be a high priority. E: aye seems that way :) > In order to pr…

The issue is during evacuation, people may not have the sense to stick to the track their train is stuck on, and may spread out into a parallel track.

That is an issue for sure, but I'm responding to the possibility of a train hitting another where the passengers have opted to stay on the halted train

Re: London trains see power cut as thousands stranded in dark for hours

#77

Post by bobthepanda »

drexlspivey wrote: post #45
uxp8u61q wrote: post #31

Earlier quoted context omitted.

If the cost for maintaining the infrastructure in 10x that, then it's a shoestring budget. You have to compare the budget to a baseline, you can't just evaluate it as an absolute. Yes, £10B looks like a big number, but what do you compare it to?

TFL is actually profitable, you could google that in less time that it would take to write this comment, these wild hypotheticals are just noise

TfL was profitable pre-covid. It is not currently profitable because remote work and such have lowered ridership, only running a surplus this year due to government support.

Re: London trains see power cut as thousands stranded in dark for hours

#78

Post by corobo »

kevincox wrote: post #74
corobo wrote: post #71

Earlier quoted context omitted.

I'd really hope that modern signalling prevents trains entering signal blocks with other trains in (or can't confirm there's no train in) them. As in actively prevents, locking the brakes at the previous block, rather than allowing drivers to miss or ignore signals. We've had plenty of issues with this to learn from in the history of railways for it not to be a high priority. E: aye seems that way :) > In order to pr…

The walking passengers may enter a block that their train has already cleared. So you can't really assume that wherever they walk will be locked.

The comment I'm responding to is concerned of the risks of staying on a halted train. No walkers in this hypothetical.

That is for sure an issue, but not the issue I'm responding to

Re: London trains see power cut as thousands stranded in dark for hours

#79

Post by vkou »

ryanjshaw wrote: post #39
vkou wrote: post #28

Earlier quoted context omitted.

You can't tell at the 10 minute mark whether or not power will be back in 10 more minutes, or in 3 hours.

But you can tell when 3 hours have passed and decide upfront - as a matter of policy - where to draw a line.

And at the 4 hour mark, the passengers were rescued. It would be ironic, of course, if the rescue train hit any one of the geniuses that smashed windows and started walking the tracks.

Re: London trains see power cut as thousands stranded in dark for hours

#80

Post by mnd999 »

taway_6PplYu5 wrote: post #11
midasuni wrote: post #8

Earlier quoted context omitted.

So people walk out after a 10 minute outage, then it’s fixed, but you can’t turn power on because a few people have decided to go for a stroll?

yes, because what if one of those people is touching the power rail? What do we know about the demographics of the people walking? How do we know they all made it out, or is someone lying down somewhere on the track?

There's no power rail. It's overhead power - that was the problem. According to the union a manager providing strike cover was responsible for damaging the overhead lines - https://www.standard.co.uk/news/transport/gwr-train-cables-p...
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