How many sizes of tube train are there? Central line trains always feel
tiny compared to, say, circles; and it makes sense that a deep tunnel
might be smaller than a cut-and-cover; is that so? Are
northern/Victoria/Piccadilly any bigger or smaller? How come metropolitan
trains feel so much bigger than circles (as big as real trains), when they
use the same track? Are they bigger, or is it just the decor? Is it
because the northern half of the circle has bigger tunnels? Does that mean
one could run real trains through them? Is there any way to get a train
from, say, the Anglia or Great Eastern lines near Liverpool St down into
the circle? Does the Thameslink tunnel stop at Moorgate? Does that mean we
could turn the West Anglia into a Retropolitan (tm) line which connected
northeast London with the northern half of the circle? Or take the the met
out to Chingford? And what's so light about the DLR? It's standard gauge,
after all. Could you in fact take one train and drive it willy-nilly over
the entire network? If so, where can i buy second-hand trains? And
finally, is it obvious i spend far too much time in the bloody tube and
have now lost my mind?

Thanks,
tom

PS Sorry this has no relevance to oyster

--
This should be on ox.boring, shouldn't it?

"Tom Anderson" wrote in message
...
How many sizes of tube train are there? Central line trains always feel
tiny compared to, say, circles; and it makes sense that a deep tunnel
might be smaller than a cut-and-cover; is that so? Are
northern/Victoria/Piccadilly any bigger or smaller? How come metropolitan
trains feel so much bigger than circles (as big as real trains), when they
use the same track? Are they bigger, or is it just the decor?

There are two main sizes of London Underground train, the "tube" and the
"subsurface". Subsurface lines are Metropolitan, Circle, District,
Hamersmith and City and East London line. All the others are built to tube
standard. The subsurface lines are about the same size as mainline (ie ex
BR) lines in terms of loading guage. All London Underground trains run on
standard guage track, and use the same electrification system.

Is it
because the northern half of the circle has bigger tunnels? Does that mean
one could run real trains through them? Is there any way to get a train
from, say, the Anglia or Great Eastern lines near Liverpool St down into
the circle?

Certainly in the past it has been possible to run through between what is
now national rail and what is now the London Underground. For example,
there were in the past services along the District side of the circle out
onto the distric line towards Barking that carried on out the LTS line to
Southend. Also in a recent thread someone talked about services from Epping
on the central line into Liverpool St. mainline. Most connections where
they do exist are not very conveninetly possitioned to make inter running
very convenient. There are a few sections where full interrunning is
possible, the main example being the norther end of the Bakerloo line where
the line is shared with tube sized 1972 stock of the district line and
Silverlink class 313 trains of mainline size. I believe it would be
possible to physically fit a WAGN type emu train or Anglia stock onto the
norther side of the circle (I have a vague recollection someone on this
newsgroup has mentioned mk 2 carriages on the circle line at some past
point), but there are no compatible electrification systems and no
convenient track connections for running services.

Does the Thameslink tunnel stop at Moorgate? Does that mean we
could turn the West Anglia into a Retropolitan (tm) line which connected
northeast London with the northern half of the circle? Or take the the met
out to Chingford?

There is no physical connnection between the "widened lines" (that is the
track used by Thameslink between KXSP and Moorgate) and the circle line any
more. The big problem with such a service would be pathing. The London
Underground is at capacity on that route, and any space for such a service
would necessitate a decrease in service on one of the other routes that uses
that track.

If these sorts of things were made to happen, we would end up with a service
on the norther half of the circle a bit like the suburban services in South
london. They would go to a lot of places, but the concept of a London
Underground style "line", with very frequent trains all going on a fixed
route would be lost. A great deal of work has been done in the past to
separate out the bits where BR as was and LU shared facilities so that
interference between service patterns and timetabling could be reduced, and
most people would say that these have been a good thing.

And what's so light about the DLR? It's standard gauge,
after all.

The term "light rail" tends to mean "modern trams or systems using that
technology" eg Metrolink, Tramlink, Supertram ... in various cities in
Britain, and similar systems in other countries. What makes the DLR light
rail is the vehicles, which are derived from a German tramway herritage, and
the tramway type track. Look at some of the curvature in the line through
the isle of dogs, and you will appreciate that this is not the same sort of
railway that LU or what was BR run.

Could you in fact take one train and drive it willy-nilly over
the entire network? If so, where can i buy second-hand trains? And
finally, is it obvious i spend far too much time in the bloody tube and
have now lost my mind?

You could physically run a train through from most of the London Underground
system to the national rail network, but there's more to it than that. A
lot of london underground stock in the past has been transported on the
national rail network for reasons like delivery of new stock. In such cases
it has run in trains hauled by locomotives with barrier waggons to permit
coupling and braking to be translated from the locomotive to the underground
stock. The reason you can't drive a train willy-nilly over the whole system
is twofold. First of all there is the problem of powering such a train, and
second, there is the problem of signalling. No London Underground lines are
designed to ventilate for diesel engines, and no non London Underground
trains can draw power from the London Underground power system. London
Underground trains to not have things like AWS and TPWS that would be
required for it to drive over the rest of the UK railway network, and even
if they did, they can't get power because nowhere but London Underground
uses that particular power supply. If you built a specific new deisgn of
train that had all the power and signalling systems, and got the relevant
safety cases and permissions and timetabling, it would be theoretically
possible for you to drive it around the whole system.

Thanks,
tom

PS Sorry this has no relevance to oyster

it's to do with transport in London, therefore it's on topic here.

Robin

Tom Anderson writes:
How many sizes of tube train are there?

Two major types, "tube" (deep tunnel) and "subsurface" (cut and cover),
as you surmise.

Central line trains always feel tiny compared to, say, circles; and
it makes sense that a deep tunnel might be smaller than a cut-and-cover;
is that so?

Yes, I just said so. Weren't you listening? :-)

Are northern/Victoria/Piccadilly any bigger or smaller?

No substantial difference. The standard tunnel is 11' 8.25" (3.56 m)
diameter on all these lines. Sections built since WW2 have slightly
larger tunnels, but for the purpose of reducing air friction rather
than making the trains larger.

Where car *lengths* are longer, the cars either have to be slightly
narrower or have a taper at the ends in order to fit around the curves.

How come metropolitan trains feel so much bigger than circles (as
big as real trains), when they use the same track? Are they bigger...?

Yes, slightly.

Is it because the northern half of the circle has bigger tunnels?

Yes, because it was built originally to take broad-gauge trains.
And the Metropolitan main line, of course, is pretty much all on
the surface.

There are actually three main flavors of subsurface train, called
"A", "C", and "D" stock, all slightly different sizes according to
which tunnels they run through.

Does that mean one could run real trains through them?

The entire subsurface system was originally designed for "real trains"
to be run through from the main line railways, and at one time there
were many track connections where trains did run through. These
included (listed from memory, but I should be pretty much correct):

* London & South Western - Turnham Green, Hammersmith
* Great Western - Ealing Broadway, Paddington
* West London - Kensington (Olympia) (modern name), Latimer Road
* Midland - St. Pancras
* Great Northern - King's Cross
* London Chatham & Dover - Farringdon
* Great Eastern - Shoreditch
* South Eastern - New Cross
* London Brighton & South Coast - New Cross Gate (modern name)

All these connections have been removed over the years, one way or
another. In some cases the through services onto another line have
ended; in two they have become the only service and the line has
changed hands. (Hammersmith to Turnham Green, now Underground;
King's Cross Thameslink [modern name] to Farringdon, now Thameslink).

Still other track connections were built for possible through services
but never used that way. There's also at least one case where the
"through" service was always effectively only the service on the line:
from about Putney Bridge to Wimbledon, the District runs on ex-L&SWR
track that the L&SWR itself never used much.

But clearances have changed over the years, and today main line trains
are generally a bit larger than Underground subsurface trains, so if
such through services were reinstated, they would probably have to use
the latter size of train.

Is there any way to get a train
from, say, the Anglia or Great Eastern lines near Liverpool St down into
the circle?

Not any more, but that's where one of those "track connnections built
for possible through services but never used that way" was. In fact,
for a little while while the Metropolitan (and Circle) line was being
built, its trains terminated at Liverpool Street main line station.

Does the Thameslink tunnel stop at Moorgate?

At Moorgate, the Thameslink tracks are side by side with the Metropolitan
(also used for Circle and H&C trains) in one tunnel. Originally this all
beloned to the Metropolitan company (and Moorgate station was then on
the surface). The combined tunnel narrows to 2-track width where the
Thameslink tracks end, so only the Metropolitan tracks continue.

Does that mean we
could turn the West Anglia into a Retropolitan (tm) line which connected
northeast London with the northern half of the circle?

No. The tracks from Moorgate to Finsbury Park are not connected to any
others at Moorgate, never have been, and it could not easily be done.
They are in deep tube, far below the Metropolitan/Circle and Thameslink
tracks. This line used to be part of the Underground, incidentally,
and was the only deep tube on the system that was built large enough
for main-line trains. However, for historical reasons it wasn't
actually used for them until about 75 years after it was built, when
it was transferred to British Rail.

Or take the the met out to Chingford?

If the junction at Liverpool Street was put back in, that could be done.
Of course it would require major work, since the main line station was
rebuilt without providing for it.

In general the reason that these most of these services were withdrawn
or never begun is that it was found more efficient to operate the lines
the way they now are. Long routes that are partly shared with other
trains are more subject to delays. (Similarly, some people feel that
the Circle Line should be withdrawn to allow the tracks to be used
more efficiently by the lines they are shared with, and so on.)

In addition, there are compatibility issues with different systems of
electric trains, plus diesels on the main lines. In the days when the
through connections I listed above were put in, the subsurface lines
of the Underground used steam locomotives -- today nothing but electric
trains would be acceptable.

And what's so light about the DLR? It's standard gauge, after all.

The trains are of lighter construction and would not be safe in a
collision with other trains. Light railways also get to economize
in other ways.

Could you in fact take one train and drive it willy-nilly over
the entire network?

The Underground has many incompatibilities between lines, including
not only differences in size but also in in signaling or automatic
train control systems, and even in the position of the live rails.
If you imagine all other trains being safely off the tracks so that
the usual safety rules didn't apply, *and* all the signal-related
systems being disabled, then I think it would be physically possible
for a Central Line train to be driven onto and over any of the other
lines you wanted. (To reach the Waterloo & City it would have to
be moved by crane, as that line has no track connections at all.)

For more information both about present and former track connections,
and about what rolling stock is normally allowed on other lines, see
Clive's Underground Line Guides http://www.davros.org/rail/culg.

is it obvious i spend far too much time in the bloody tube and
have now lost my mind?

Yep. Pleased to meetcha.
--
Mark Brader "You have a truly warped mind.
Toronto I admire that in a person."
-- Bill Davidsen

My text in this article is in the public domain.

In message ,
Tom Anderson writes
How many sizes of tube train are there?
[...]
PS Sorry this has no relevance to oyster


Last week, taking a spell on the platforms away from Oyster stuff, I
saw a train which was much lower than anything else that runs on our
District/Hammersmith & City tracks.
I was told (thanks Ray B) that it was probably the Track Recording
Train.
--
Kat Me, Ambivalent? Well, yes and no.

First up, many thanks to Robin and Mark for their comprehensive answers.

Now, turning back to my grandiose plans / poorly camouflaged irritation
about living in northeast London ...

On Sat, 10 Jan 2004, Robin Payne wrote:

"Tom Anderson" wrote in message
...

Does that mean we could turn the West Anglia into a Retropolitan (tm)
line which connected northeast London with the northern half of the
circle? Or take the the met out to Chingford?

If these sorts of things were made to happen, we would end up with a
service on the norther half of the circle a bit like the suburban
services in South london. They would go to a lot of places, but the
concept of a London Underground style "line", with very frequent trains
all going on a fixed route would be lost.

How so? I'm suggesting extending one end of the Met a bit (well, a lot)
further on, that's all. Even if the whole suburban part of the West Anglia
line was assimilated, the Met already splits into two major branches at
Harrow-on-the-Hill, so having a split at the other end, at Hackney Downs,
is only making it more symmetric. Still nowhere near as bad as the
District line. Alternatively, taking West Anglia trains beyond Liverpool
Street (say as far as Baker Street, for symmetry's sake) wouldn't make
that any less of a line.

As for the feel of the services at those stations, they already have three
lines to four or more termini, so one or two more won't hurt, surely?
Especially if it was an extended Metropolitan.

Anyway, train incompatibilties being as they are, we'll have to wait for
stock with on-board fusion reactors for all this anyway.

PS Sorry this has no relevance to oyster

/joke

it's to do with transport in London, therefore it's on topic here.



tom

--
eviscerated by obfuscation

On Sat, 10 Jan 2004, Mark Brader wrote:

Tom Anderson writes:

How come metropolitan trains feel so much bigger than circles (as
big as real trains), when they use the same track? Are they bigger...?

Yes, slightly.

Also, having paid attention while on board, i notice that the circle
trains have more handholds; vertical pillars at the ends of runs of seats,
and a double rail hanging from a bulge in the ceiling. Met trains don't
have these (but do have luggage racks!), and so feel more spacious. I
suppose it's because they're for low-density long-haul trips in from the
far suburbs, whereas the circle is for high-density short-haul trips
between major NR termini and around town.

But clearances have changed over the years, and today main line trains
are generally a bit larger than Underground subsurface trains, so if
such through services were reinstated, they would probably have to use
the latter size of train.

On a semi-related note, i saw that continental freight trains are a bit
bigger than ours, and so can't run on our network, making the chunnel a
bit useless for freight services; eurotunnel are planning to build a
freight terminus somewhere in Kent or something to tempt them though.

In general the reason that these most of these services were withdrawn
or never begun is that it was found more efficient to operate the lines
the way they now are.

But transport requirements change!

Long routes that are partly shared with other trains are more subject to
delays.

Fair enough.

Although (and please excuse my continued frenzied flogging of this
particular expired equine - it's almost over now) merging the Met and the
West Anglia suburban services (using the circle-to-surface interconnect at
Liverpool Street which currently exists only in my mind - modelled after
Oblivion at Alton Towers, i think) wouldn't create any new services, so
conflict shouldn't increase too much (i suppose you would then get delays
in one part affecting the other, which you don't at present).

(Similarly, some people feel that the Circle Line should be withdrawn to
allow the tracks to be used more efficiently by the lines they are
shared with, and so on.)

Yikes! That would be pretty radical.

tom

--
eviscerated by obfuscation

In article ,
Tom Anderson writes
How many sizes of tube train are there?

Lots.

Central line trains always feel
tiny compared to, say, circles; and it makes sense that a deep tunnel
might be smaller than a cut-and-cover; is that so?

Yes. There are two basic sizes: Tube Stock, and Sub-Surface Stock.

How come metropolitan
trains feel so much bigger than circles (as big as real trains), when they
use the same track?

A Stock on the Metropolitan is wider than C and D stock; you'll notice
it can seat five across. As such, it's restricted to certain routes. D
stock is slightly longer than C stock, and is therefore banned from
parts of the subsurface lines (notably between Edgware Road and both
Hammersmith (Met.) and High Street Ken.).

The tube trains have detail differences which are described on my web
site. For example, 1967 stock doesn't have tripcocks while 1992 stock
has "high-lift" shoegear.

Is it
because the northern half of the circle has bigger tunnels? Does that mean
one could run real trains through them?

Yes.

Is there any way to get a train
from, say, the Anglia or Great Eastern lines near Liverpool St down into
the circle?

There's no track connection at present. The connections between LU and
National Rail are listed on my web site.

Does the Thameslink tunnel stop at Moorgate?

Yes, and always did even when it wasn't a tunnel.

--
Clive D.W. Feather, writing for himself | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
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