Are tunnel walls the closest object to a train?

[Cricketer8for9]

Oxted tunnel is apparently the loading gauge limitation on Southern.

 

[choochoochoo]

Out of interest, what would happen if you needed to have emergency egress whilst in a single line tunnel with tight clearance given not all units are equipped with nose-end doors.

Would there be regular sections in the tunnel that would have to have sufficient clearance to permit safe egress through a side door ?

 

[MarkyT]

As mentioned above, Ledbury Tunnel in Herefordshire has or had special rules due to its restrictive bore. I understand Shakespeare Tunnel in Kent has similarly unique rules.

Out of interest, what would happen if you needed to have emergency egress whilst in a single line tunnel with tight clearance given not all units are equipped with nose-end doors.

When planning for SE domestic HS1 services in Kent, the twin single bore Shakespeare tunnels near Dover presented a major problem for emergency egress from the new Hitachi trains which clearly have no end doors in their pointy noses. A solution was found to move the tracks within each bore slightly to one side of the centre line. This created sufficient space on one side of these fairly generously proportioned tunnels that it was considered safe enough for passengers to exit the sliding side doors in an emergency and get down to track level for evacuation. If this solution had not been feasible, it's entirely possible the new trains would not have been cleared to run on this particular route segment, so as a back-up, a connection between the SE and LC&D lines at Canterbury was considered to allow the 395s to reach Dover; that idea has been looked at many times for various reasons and would also have allowed the Folkestone-Dover section to be closed entirely if more cliff slippage had occurred making long term maintenance unviable. I believe in HST days, the Ledbury procedure would have been to direct escaping passengers to a sliding side door in the parcels area of one of the power cars. Entirely new single-track tunnels are usually equipped with a platform height walkway throughout on one side. In double track tunnels, the accepted escape route is usually via the other track, closed to traffic clearly, using normal side doors to alight. A train can also be brought alongside and special bridging ramps used at doorways to facilitate evacuation.

 

[island]

Out of interest, what would happen if you needed to have emergency egress whilst in a single line tunnel with tight clearance given not all units are equipped with nose-end doors.

Would there be regular sections in the tunnel that would have to have sufficient clearance to permit safe egress through a side door ?

If a unit cannot be evacuated effectively in a tunnel for whatever reason, then the unit wouldn’t be cleared to enter the tunnel.

Northern City Line only allows 717s (and previously 313s) for this reason.

As mentioned above, the Ledbury tunnel had similar issues with HST doors unable to be opened whilst in the tunnel. The evacuation procedure for a HST that became stranded in the tunnel would have been via the power cars, which have sliding doors. And the guard was required to travel in the rear power car whilst entering and in the tunnel, in case an evacuation became necessary. This is no longer relevant of course with the 800s having taken over.

 

[TheVicLine]

Surely a platform edge is closer to the train than a tunnel wall.

 

[Mcr Warrior]

From a window height.

Surely a platform edge is closer to the train than a tunnel wall.

Probably is, but the OP specified from window height.

 

[TheVicLine]

Probably is, but the OP specified from window height.

Oh yeah, only read the title. A train wash then?

 

[choochoochoo]

If a unit cannot be evacuated effectively in a tunnel for whatever reason, then the unit wouldn’t be cleared to enter the tunnel.

Northern City Line only allows 717s (and previously 313s) for this reason.

As mentioned above, the Ledbury tunnel had similar issues with HST doors unable to be opened whilst in the tunnel. The evacuation procedure for a HST that became stranded in the tunnel would have been via the power cars, which have sliding doors. And the guard was required to travel in the rear power car whilst entering and in the tunnel, in case an evacuation became necessary. This is no longer relevant of course with the 800s having taken over.

I was of the understanding that 717s and 313s were specially built to fit the NCL. Otherwise you could have sent a nose-end door-equipped 387 down there, provided it had trip-cocks installed and suitable ladders for the egress.

The offset track makes sense in old single line tunnels.

Still go through some tunnels on the route I drive and think it'd be a tight squeeze to get out of here in an emergency, even with sliding doors rather than slam doors.

 

[VEP3417]

i know were not including foliage but a thumper railtour to fawley power station i was on had a bit of trouble with a slightly fallen over tree, i think thats the driver looking out so you can see how close it is, lucky they have thos ugly window bars on the train aye
still diddnt stop a kitchen staff member (or something along thos lines) having a go at my friend for looking out of the window....
not sure how you can look out with bars on .... no other staff member had problems with us standing at the window area, but this person made a big old fuss walking past us every now and again to check.....
i wonder how long it will be for all railtours to have bars on or a rule where your not aloud to look out, thats part of the reason people go on tours as its the only place you still can look out of a window! well apart from heritage railways but again there might come a point where you cant!

 

[theageofthetra]

When planning for SE domestic HS1 services in Kent, the twin single bore Shakespeare tunnels near Dover presented a major problem for emergency egress from the new Hitachi trains which clearly have no end doors in their pointy noses. A solution was found to move the tracks within each bore slightly to one side of the centre line. This created sufficient space on one side of these fairly generously proportioned tunnels that it was considered safe enough for passengers to exit the sliding side doors in an emergency and get down to track level for evacuation. If this solution had not been feasible, it's entirely possible the new trains would not have been cleared to run on this particular route segment, so as a back-up, a connection between the SE and LC&D lines at Canterbury was considered to allow the 395s to reach Dover; that idea has been looked at many times for various reasons and would also have allowed the Folkestone-Dover section to be closed entirely if more cliff slippage had occurred making long term maintenance unviable. I believe in HST days, the Ledbury procedure would have been to direct escaping passengers to a sliding side door in the parcels area of one of the power cars. Entirely new single-track tunnels are usually equipped with a platform height walkway throughout on one side. In double track tunnels, the accepted escape route is usually via the other track, closed to traffic clearly, using normal side doors to alight. A train can also be brought alongside and special bridging ramps used at doorways to facilitate evacuation.

I think that's why Networkers aren't cleared for that tunnel.

 

[XAM2175]

i wonder how long it will be for all railtours to have bars on or a rule where your not aloud to look out

Regardless of whether or not you're allowed to look out of the window, the ORR expects all heritage stock running on the national network to have lockable windows by 31 March 2023.

 

[Deepgreen]

Regardless of whether or not you're allowed to look out of the window, the ORR expects all heritage stock running on the national network to have lockable windows by 31 March 2023.

When the day comes that people cannot look out of a window I shall be gone. Leaning out, however...

Oh yeah, only read the title. A train wash then?

If we take it to non-passenger carrying (and no reason why not), many more depot area options come into play. Meanwhile - single line token (at exchange).

Regardless of whether or not you're allowed to look out of the window, the ORR expects all heritage stock running on the national network to have lockable windows by 31 March 2023.

As a matter of interest does that mean fully closed, or openable to a fixed point for ventilation and then unlockable for the full drop?

i know were not including foliage but a thumper railtour to fawley power station i was on had a bit of trouble with a slightly fallen over tree, i think thats the driver looking out so you can see how close it is, lucky they have thos ugly window bars on the train aye
still diddnt stop a kitchen staff member (or something along thos lines) having a go at my friend for looking out of the window....
not sure how you can look out with bars on .... no other staff member had problems with us standing at the window area, but this person made a big old fuss walking past us every now and again to check.....
i wonder how long it will be for all railtours to have bars on or a rule where your not aloud to look out, thats part of the reason people go on tours as its the only place you still can look out of a window! well apart from heritage railways but again there might come a point where you cant!

You can look out of all glass windows. However you can only lean out of a few these days. Maybe your friend was perceived to be risking injury, given the overgrown nature of the route (which was the point of your post), and which would have lain at the door of the organisers if it had occurred? For those that think they are 'window-savvy' and know better than to get caught out, consider the Balham fatality of a keen rail enthusiast and preserved railway volunteer.

 

[Bedpan]

Just out of pure interest, I know some tunnels have a tight bore but which has the tightest bore ?

Surprised that nobody has mentioned the tunnels on the Tonbridge - Hastings line which were so narrow that special units with a narrow body profile had to be built to operate over the line until the lines through the tunnels were singled in the 1908s.

The tunnels had been built on the cheap and were found to be inadequately lined, such that additional courses of brick lining had to be built inside the tunnels, so making them narrower.

 

[MarkyT]

Surprised that nobody has mentioned the tunnels on the Tonbridge - Hastings line which were so narrow that special units with a narrow body profile had to be built to operate over the line until the lines through the tunnels were singled in the 1908s.

The tunnels had been built on the cheap and were found to be inadequately lined, such that additional courses of brick lining had to be built inside the tunnels, so making them narrower.

The tunnels either side of Tunbridge Wells station remain double-track even though they suffered from the same construction quality and clearances problems as others on the line that were singled. This was managed in this specific case by installing slab track to more accurately keep the rails in the correct position. The line speed through the station tunnels is also comparatively low, which limits lateral vehicle oscillations, hence dynamic clearance allowances can be reduced.

 

[CEN60]

Nobody has mentioned a train on the next track. What is the closest approach you would get?

IIRC, wasn't there a potential issue of an APT tilting the wrong way and potentially contacting a train tilting the right way on the opposite track?

Normal passing (for non tilting stock) = >100mm.

What you refer to in your post is called "wrong side tilt failure) - its been a while but if I recall correctly the passing clearance if one tilting train has failed wrong side is 25mm to normal non-tilting stock. The standard does not require a check for 2 wrong side tilt failures on adjacent tracks (the odds as I understand things are very small - and tilt failure trains would be taken out of service (or stopped) so the chances of meeting another are almost (almost!!!) nil.

 

[VEP3417]

Regardless of whether or not you're allowed to look out of the window, the ORR expects all heritage stock running on the national network to have lockable windows by 31 March 2023.

oh...well better get a few last rail tours in then...

 

[Pete78]

Just found this one

which definitely places track workers as the closest thing to the train

 

[quantinghome]

Just out of pure interest, I know some tunnels have a tight bore but which has the tightest bore ?

London Underground I would think. The minimum deep tube diameter is 11 ft 8 in. Some parts of the Northern line were 10 ft 6 in prior to re-boring in the 1920s. When new trains were bought for the Northern line in the 1990s the tunnel lining segment flanges has to be ground down in places to achieve clearance.

On the national network I'm not sure. The Northern city line tunnels are about 16 ft diameter which are pretty tight.

 

[Jona26]

Class 501 units that worked the Watford DC and North London lines had window bars fitted due to limited clearance through the Hampstead tunnels.

 

[Peter Sarf]

Nobody has mentioned a train on the next track. What is the closest approach you would get?

IIRC, wasn't there a potential issue of an APT tilting the wrong way and potentially contacting a train tilting the right way on the opposite track?

I remember as a young lad having my face slightly out of the window as we passed Slade Green. It was slam door stock - non corridor so probably EPB. After passing I sat down. Then, in the next tunnel, crash bang wallop. The door I had been standing at was ripped open and off its hinges !. I was sat next to it and to say I was shocked was an understatement. I pulled the emergency cord. I don't know how soon we stopped but we stopped at the next station. The guard came up and was busy accusing me of opening the door. Would not let go of it. I was too shocked to reply. Eventually a railway police officer turned up and asked the guard how this lad could possibly have done all that damage further forwards along our train !. He showed it to me and it extended forwards along the side of the next carriage. Transpired we had hit an open door on a passing train.

I could have been labeled a vandal for life !. It makes me wonder if I should have pulled the cord or just walked along the coach instead.

So you never know where the next obstruction might be !.

 

[TRAX]

London Underground I would think. The minimum deep tube diameter is 11 ft 8 in. Some parts of the Northern line were 10 ft 6 in prior to re-boring in the 1920s. When new trains were bought for the Northern line in the 1990s the tunnel lining segment flanges has to be ground down in places to achieve clearance.

On the national network I'm not sure. The Northern city line tunnels are about 16 ft diameter which are pretty tight.

Isn’t the Glasgow Subway even tighter ?