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0 pointsyabones2y ago0 comments

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...

0 comments

stuaxo2y ago

The line by paddington has long sections where the tube runs in parallel, in one of the pictures you can see a lot of people walking towards a tune depot and somebody is crossing one of the lines with a middle rail which is part of their DC electrification system (I assume this had been turned off - but this may have been turned off because they realised people were on the line, not the other way round).

quietbritishjim2y ago

In this case, one quote I've seen is that a train's pantograph was "caught up" in the overhead wires and dragging them along, which makes it sound like some were now on the ground target than overhead.

nicoburns2y ago

The Elizabeth line also has an actual walkway for emergency (and presumably also maintenance) purposes.

Symbiote2y ago

The newly built sections under central London, but lots of the Elizabeth Line is using older track.

NoMoreNicksLeft2y ago

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

corobo2y ago

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...

kevincox2y ago

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.

1 more reply

bobthepanda2y ago

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.

1 more reply

Symbiote2y ago

No, not in the slightest.

j / k navigate · click thread line to collapse

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stuaxo2y ago

quietbritishjim2y ago

nicoburns2y ago

The Elizabeth line also has an actual walkway for emergency (and presumably also maintenance) purposes.

Symbiote2y ago

The newly built sections under central London, but lots of the Elizabeth Line is using older track.

NoMoreNicksLeft2y ago

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

corobo2y ago

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 :)

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

kevincox2y ago

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.

1 more reply

bobthepanda2y ago

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.

1 more reply

Symbiote2y ago

No, not in the slightest.

j / k navigate · click thread line to collapse