What would happen if the power failed totally?

[Comstock]

They must have a plan for this, it may even have happened?

So imagine the tube is totally without power. How do they get everyone out?

Do they keep diesel shutters especially for this? Or battery powered ones?

Or do people simply have to walk to the nearest station?

 

[Bletchleyite]

Or do people simply have to walk to the nearest station?

That one.

 

[Comstock]

Wow! Heaven help anyone who can't walk very far.

 

[Bletchleyite]

Wow! Heaven help anyone who can't walk very far.

Same as any train evacuation, they would need to be assisted. On a stretcher to a point if required.

 

[Vespa]

Do any of the trains have batteries for emergency movement to the next station ?
If not I would looking at retro fitting as well as emergency generators.

 

[Whistler40145]

I’m sure London Underground have several battery locomotives that could be used in an emergency

 

[Domh245]

Do any of the trains have batteries for emergency movement to the next station ?
If not I would looking at retro fitting as well as emergency generators.

No traction batteries and there's no space to retrofit them, nor emergency generators. For the amount of times this is an issue, the great expense and difficulty of installing a backup makes no sense at all

I’m sure London Underground have several battery locomotives that could be used in an emergency

Given the density of the services, limited number of Battery locos, and where they are kept (Acton and Ruislip are the only regular locations IIRC), there's no practical way of rescuing trains with battery locos.

 

[Dstock7080]

Given the density of the services, limited number of Battery locos, and where they are kept (Acton and Ruislip are the only regular locations IIRC), there's no practical way of rescuing trains with battery locos.

All battery locos are based at Ruislip now and currently unable to couple to passenger Stock

 

[Whistler40145]

All battery locos are based at Ruislip now and currently unable to couple to passenger Stock

So job stopped

 

[Domh245]

Yes, although if all the power went off, you'd also lose signalling, etc so even if there was a means of rescue or limping it to the next station you won't be able to do anything beyond that.

 

[Lewlew]

Same as any train evacuation, they would need to be assisted. On a stretcher to a point if required.

Every train carries a stretcher/carry sheet for this reason

 

[Meerkat]

Every train carries a stretcher/carry sheet for this reason

Should have a fold out frame with little wheels - there are rails down there to make things easy!
In this zero power nightmare would there still be communication? The driver can’t start walking people out without knowing that the power won’t come back on at any moment.

 

[py_megapixel]

Should have a fold out frame with little wheels - there are rails down there to make things easy!
In this zero power nightmare would there still be communication? The driver can’t start walking people out without knowing that the power won’t come back on at any moment.

Are there not procedures to ensure that the traction current is off in the event of a derailment or a train failure (shorting the live rail to the neutral IIRC)? Presumably the driver would have to apply those procedures so that even if the current came back on, the rails would not be live. Just my speculation though.

 

[Enthusiast]

Are the tunnel telephone system wires still active? I know they were not installed on the Heathrow 4 and 5 extensions or the Jubilee extension. I believe pinching them together cut the traction current (though I confess my knowledge of that system is sparse and almost certainly outdated).

 

[Dstock7080]

Are the tunnel telephone system wires still active?

All decommissioned now.

 

[Comstock]

This is a pretty good argument against driverless trains actually isn't it?

I'd be happy to help carry a stretcher, as I'm sure would many other people, but I'd want a trained staff member in front of me.

 

[philthetube]

Unless it is going to take a seriously long time people would not be carried out, all who can walk would and the rest could wait.

Being in the dark on a crowded train is not good, sitting on a train with a few others, also not walkers and a couple of lamps is not a huge issue.

Evacuating a train with a carry sheet would not be done without ambulance and fire brigade present unless there was a dire emergency.

 

[Islineclear3_1]

I'm sure there is emergency lighting on the trains and in the tunnels and so there wouldn't be complete darkness

 

[Vespa]

I personally think traction batteries should be fitted to new tube trains just for this scenario so the trains can get to the next station and evacuate, this can be used for depot movement too.

I believe class 777 is fitted with traction batteries.

 

[Domh245]

I personally think traction batteries should be fitted to new tube trains just for this scenario so the trains can get to the next station and evacuate, this can be used for depot movement too.

I believe class 777 is fitted with traction batteries.

Given the low floors and general lack of space under the floor, I don't see where you think they can be fitted, the fitment of aircon/cooling units into that space is naturally higher priority, especially given the relative rarity of complete powercuts like described. Depot movements can be done using the 4th rail where present and shed leads where not, exactly as it is now.

Going by this database, the average distance between stations is 1.3km, so on average you're never more than 650m away from a station - in reality often less because the busy underground sections are far more dense in terms of stations and that's got quite a few misleadingly large ones as well such as the fast sections of the Metropolitan and Piccadilly lines. Walking 650m even in the particularly harsh environment of a railway (or tube tunnel) isn't enough of a justification for the expense and complication of batteries IMO

 

[Whistler40145]

Presumably all stations that are a distance from the surface are all fitted with emergency lights and the same inside the tunnels?

 

[Dstock7080]

Presumably all stations that are a distance from the surface are all fitted with emergency lights and the same inside the tunnels?

Indeed, traction- station lighting- tunnel lighting are from separate supplies, many stations are also changing to back-up battery/stored energy emergency systems.

 

[Meerkat]

Indeed, traction- station lighting- tunnel lighting are from separate supplies, many stations are also changing to back-up battery/stored energy emergency systems.

So if there was an region wide power cut some tunnels and stations would immediately go dark?!

 

[Vespa]

Given the low floors and general lack of space under the floor, I don't see where you think they can be fitted, the fitment of aircon/cooling units into that space is naturally higher priority, especially given the relative rarity of complete powercuts like described. Depot movements can be done using the 4th rail where present and shed leads where not, exactly as it is now.

Going by this database, the average distance between stations is 1.3km, so on average you're never more than 650m away from a station - in reality often less because the busy underground sections are far more dense in terms of stations and that's got quite a few misleadingly large ones as well such as the fast sections of the Metropolitan and Piccadilly lines. Walking 650m even in the particularly harsh environment of a railway (or tube tunnel) isn't enough of a justification for the expense and complication of batteries IMO

You do have some point in this respect, I was considering passenger safety in the first instance, keeping everybody safe inside the train and discharging them at the stations, the other, a worse case scenario if the power comes back on while you're still walking along the tunnel, it would be very serious.

The only other thing I could consider is to keep a back up generator so enough power in the short term even up to shunting speed to get to the stations.

I would rather keep passengers on board than milling about in a high risk environment.

 

[frediculous]

Re: emergency lights. Not only that but 99% of Underground passengers probably carry a smartphone with torch capability

 

[Islineclear3_1]

So if there was an region wide power cut some tunnels and stations would immediately go dark?!

Most probably but then the emergency supply kicks in...

 

[Islineclear3_1]

You do have some point in this respect, I was considering passenger safety in the first instance, keeping everybody safe inside the train and discharging them at the stations, the other, a worse case scenario if the power comes back on while you're still walking along the tunnel, it would be very serious.

During emergency evacuation, it is highly unlikely that the power will come back on. Someone will know that the emergency services, staff and passengers are being egressed along the track...

 

[Domh245]

You do have some point in this respect, I was considering passenger safety in the first instance, keeping everybody safe inside the train and discharging them at the stations, the other, a worse case scenario if the power comes back on while you're still walking along the tunnel, it would be very serious.

The only other thing I could consider is to keep a back up generator so enough power in the short term even up to shunting speed to get to the stations.

I would rather keep passengers on board than milling about in a high risk environment.

Again, fitting things like an emergency generator is nigh-on impossible, so can't and won't happen.

Needless to say that if an evacuation needs to take place, the train is protected first by placing down Short Circuiting Devices . This means that even if the power is restored mid-evacuation the rails won't suddenly go live.

 

[yorkie]

This is a pretty good argument against driverless trains actually isn't it?

I'd be happy to help carry a stretcher, as I'm sure would many other people, but I'd want a trained staff member in front of me.

DLR is driverless but has trained staff. But I agree that having each train staffed is a good idea.

 

[bramling]

During emergency evacuation, it is highly unlikely that the power will come back on. Someone will know that the emergency services, staff and passengers are being egressed along the track...

In theory it would be possible to have a detrainment take place without any controlling minds knowing. Indeed if my memory is right this more or less happened on the Piccadilly Line on 7/7 - albeit control knew something was massively wrong just not exactly what.

In such a situation the driver would lay SCDs, which should discharge the juice if not already happened, and most importantly prevent accidental recharge by immediately causing the circuit breakers to trip should anyone attempt a recharge.