On Thu, 4 Dec 2008 12:16:50 +0000, Roland Perry
wrote:

I grew up there, and to my eyes it has been vastly "over-developed" with
fill-in housing, medium sized office blocks, and bits of shopping mall
tacked onto what was once quite a traditional High Street. They've even
built flats on the old bus station (next to the train^H^H railway
station).

The new bus station is quite a nice job though.

Neil

--
Neil Williams
Put my first name before the at to reply.

In message
"Andrew Heenan" wrote:

"Graeme Wall" wrote ...
By an amazing coincidence Shenfield
has the facilities to allow the trains to terminate and return to
London.
So have Margate, Uckfield and Blackpool, I think.
But, again by a bizzare coincidence, none of them are served fron
Liverpool
Street. Do you see a trend forming?

Yup: a trend of proposing services based on capacity and convenience, not
need or future benefit.
It's a sad trend, when a bit of imagination could be so rewarding.

Did you not pay attention when told why the current services went to
Shenfield?


On that basis, they should have built the motorways in a straight line out
into the North Sea.

Now there's a thought!

A fairly pointless one, what are you on about?

--
Graeme Wall
This address is not read, substitute trains for rail.
Transport Miscellany at http://www.greywall.demon.co.uk/rail/index.html

On Thu, 4 Dec 2008, Roland Perry wrote:

In message , at 16:29:53
on Thu, 4 Dec 2008, Tom Anderson remarked:
Shenfield is OK, but a bit of a luxury in terms of build cost,

What build cost? The line's already there and working perfectly. It has
OHLE. I have a feeling the platforms are even the right length (mostly).

2/3 of the current crossrail budget would appear to be tarting up
existing lines.

I imagine quite a bit of that is depots, a control centre, and other
one-off infrastructure. Although obviously i'm only sourcing numbers from
my colon here.

and inconveniently distant if the Crossrail trains are
all-station-stoppers.

Aren't Shenfield trains stoppers already?

Maybe - but when I lived there a significant number of long distance
trains had their penultimate stop at Shenfield.

Oh yes, good point. I assume we'll still have these on the fast lines,
right?

And then there were a whole bunch more that stopped every station to
Harold Wood then fast to Stratford.

Ah, didn't know about those, thanks.

tom

--
I'm angry, but not Milk and Cheese angry. -- Mike Froggatt

On 2008-12-04 18:31:46 +0000, Tom Anderson said:

On Thu, 4 Dec 2008, Robert wrote:

On 2008-12-04 16:24:15 +0000, Tom Anderson said:

On Thu, 4 Dec 2008, Andrew Heenan wrote:

(And please don't tell me there's not one station on the Eastern that
is more appropiate than Shenfield - or I, and many others, will cease
to believe a word you say.)

As it happens, i also think there's no better option than Shenfield.
The GEML is four-track to Shenfield, and has two two-track branches
beyond that. That means you can run Crossrail as a stopping service to
Shenfield with one pair of tracks entirely to itself, and leave the
other pair for non-stop long-distance services, with no possibility of
performance pollution between the two. Running those Crossrail trains
beyond Shenfield supplies residents of those towns with a stopping
service into London which they simply won't use. Making some of the
Crossrails non-stop on the fasts to points beyond Shenfield, and
filling in the deficit on the slow lines with Liverpool
Street-terminating trains, throws away the advantages of segregation.
Turning some of the Crossrails off short of Shenfield - say up the West
Anglia, to suburban destinations or Stansted, means taking trains away
from the stations towards Shenfield, which means a net reduction in
service on an already overcrowded line. So, we have one useless option,
one impractical one, and one actively harmful one.

I look forward to hearing your suggestion.

To balance peak hour loadings between trains running on the same Line
on the RER in Paris, the stopping patterns are varied. For example on
the western arm of the Line A, most trains ran through to the terminus
at St. Germain-en-Laye, but some turned back before the end of the line
at Le Vesinet-Le Pecq. The longer distance trains tended to skip some
of the stations nearer Paris which were covered by the trains which
turned back early. All of the trains stopped at all of the stations in
the central section. This was all done on a 2 track railway and it
seemed to work very well. Outside the central section I would suggest
that not all the Crossrail trains should be all-stations.

The only point to this that i can see is to guarantee that passengers
on the inner section have a chance to get seats; if all trains ran the
whole way, passengers from the outer section would all get a seat, and
get all of the seats, leaving none for the poor inner sectioners. The
flip side of this is that some people coming from the outer section
will have to stand, despite having further to travel than anyone from
the inner section.

That was, I think,the main reason. The maximum journey length was about
25 minutes from Étoile. The lack of seats problem arose mainly in the
evening peaks when trains leaving the central section were full and
standing. I lived there about 12 years ago and I seem to remember that
there was a pattern of 3 trains every 10 or 12 minutes down the St.
Germain branch. Also using the central section tracks on the Line A
were the dual-voltage trains to both Poissy and Cergy which diverged at
Nanterre-Prefecture. So there were trains every 90/120 seconds or so in
the central section which had automatic train control. In the opposite
direction, as St. Germain was a terminus, you could practically always
get a seat in the morning peak. The St. Germain trains were always 3
sets of 3-car emus, I forget the class number but they were built in
the 50s; the Cergy/Poissy trains were modern aluminium bodied 4-car
units running in pairs. The total train length was the same for both
types.


Specifically, the arrangement can't make the long-distance trains much
faster. Since trains can't overtake on a two-track railway (without
passing loops, anyway - do they have those?), then assuming that
stopping trains are all evenly spaced, the most time that a skipper can
save is equal to the interval between stoppers - if it sets out from
the central section just ahead of one stopper, it can reach the
turnback point just behind another one. If the trains all come out of
the core evenly spaced, skippers and stoppers, then the maximum gain is
the time between a skipper and a stopper - half the interval between
stoppers, if they're half and half.

There were no passing loops, except at Le Vesinet-Le Pecq where the
central reversing siding had 2 platform faces, being the insides of the
up and down island platforms. In my previous post I forgot that trains
could also be reversed in 2 bays at Rueil-Malmaison, but that was
mainly to be able to get trains into and out of the maintenance depot
there.

Crossrail is going to run at 12 tph along the GEML, along with another
6 tph of Liverpool Street trains. That's 18 tph, or a train every 3
minutes 20 seconds, that also being the maximum saving a skipper could
make. That doesn't seem like much of a saving over the 36 minutes it
currently takes to run from Stratford to Shenfield, particularly when
compared to the 17 minutes it takes non-stop on the fasts.

3min 20 secs! That's terrible. Modern metros should be able to run 30
tph or more. I've lived in both Paris and Munich - both cities can
manage that frequency. This country is backward!

Bear in mind that this would represent a cut in stopping train service
on that line from 16 tph to 9 tph. If you introduced more Liverpool
Street stoppers to make up the difference, you'd cut the time saving
for the skippers even further.

Another alternative along these lines is a skip-stop service, where
half the trains skip half the stops, and half skip the other half. This
does actually let you get trains from one end of the line to the other
faster, although not a lot faster in practice, i believe. There isn't a
capacity issue, as although the frequency at each station is halved,
the trains which call are each serving half the number of stations. It
does double the average waiting time for a train, but at 18 tph, that's
from 3:20 to 6:40, which is still a reasonable turn-up-and-go
frequency. It doesn't really help you run trains beyond Shenfield,
though.

tom


--
Robert

On Dec 4, 8:24*pm, "Peter Masson" wrote:
"Roland Perry" wrote



Maybe - but when I lived there a significant number of long distance
trains had their penultimate stop at Shenfield. And then there were a
whole bunch more that stopped every station to Harold Wood then fast to
Stratford.

With the increase in longer distance commuting there's no longer room on the
Fast Lines for Harold Wood and Brentwood commuters, so peak trains on the
Fast Lines are non-stop from Liverpool Street or Stratford to Shenfield or
beyond. This means that Brentwood and Harold Wood commuters have to take a
stopping train on the Slow Lines (some run fast Ilford to Stratford), but it
also eliminates peak trains crossing between Fast and Slow Lines west of
Shenfield.

The main change I seem to remember is in the off-peak, when the
stoppers got extended from Gidea Park to Shenfield all day instead of
just the peaks, so Brentwood and Harold Wood got more frequent
services but longer journey times.

They used to be served by trains from Southend (or Southminster) which
then did Romford and Stratford or Romford, Ilford and Stratford. I am
pretty sure that they used the slow lines though.

The peak services from Brentwood and Harold Wood were more stopping
than the off-peak, but I think generally non-stop from Ilford to
Stratford and quite similar to now, when the peak is the only time
that the all stations start from Gidea Park.



In operational terms running Crossrail exclusively on the Slow
Lines as far as Shenfield * makes sense. Some should probably turn back at
Gidea Park, and there's a case for running more trains on this branch in the
high peak, at the expense of Abbey Wood trains, so that non-Crossrail
stopping trains between Shenfield and Liverpool Street (Main) can be
eliminated.

Peter

On Thu, 4 Dec 2008, Andrew Heenan wrote:

"Tom Anderson" wrote...
So how were you able to determine that Shenfield was such a bad terminus?
That's the bit i can't work out.

Well, I've explained about 15 times, including in the post you replied to,
but I'm happy to try again.

No, you haven't explained it once. You still don't here. Read the question
again: how can you judge Shenfield to be the wrong terminus, when you
can't judge any other option?

I happen to believe that planning multi-billion pound investments of
taxpayers money (plus about 0.005% added by 'business') should be based on
positive reasons, rather than convenience.

But there's gaping hole in the list of reasons for Crossrail *to* go there.
Other than convenience.

If we use the word 'feasibility' rather than 'convenience', does that make
things any clearer?

And even the convenience arguments are flawed. Crossrail does not *have*
to be an all-stopper; that was a preference of Ken's, who wanted
Crossrail to be a 'supa tube' for London; Thank God he did, because his
support was key in getting the thing accepted, and that's why he got his
way. But he's not the only political opportunist, and I can see poweful
arguments for some trains that stop at all central stations, but go fast
(or faster, at least) at the ends; Heathrow is one obvious example,
Cambridge would be another. Oxford another.

You're right, Crossrail doesn't have to be an all-stopper.

But what it does have to be is completely, or almost completely,
segregated from non-Crossrail lines. Without that, it becomes a recipe for
monstrous performance pollution between railways on different sides of
London - for instance, if it shared tracks with services on the Great
Eastern and West Coast routes, then problems at Milton Keynes could end up
disrupting services in Chelmsford. This would be a really bad idea.

In practice, this means that Crossrail gets to take over one pair of
tracks on one or two routes on each side of the core tunnel. Those could
be fast or slow pairs, making it an express or stopping service. It could
be one of each, even on the same route. But any more than that, and the
core tunnel won't be able to supply enough trains to provide an adequate
service on its own.

That means that if we want a service along the GEML and the tunnel to
Abbey Wood, then on the GEML, Crossrail can take over either the fast or
the slow lines, but not both, and it can't share both with Liverpool
Street trains. That just would not work in practice.

So, if you want to run stopping services on the GEML, you *can't* also run
fast services. You could run fast services instead, but not as well.

Now, you could indeed do that - and there was a competing proposal called
Superlink which never quite got off the ground, but would have run to
Cambridge, Ipswich and Southend in the east, with stops only at Liverpool
Street and Canary Wharf inside London. There's certainly a case to be made
for this - although there might be more tunnelling (there was in that
plan), there's less construction in built-up areas, and because fares are
higher, more revenue to pay for it.

But it seems that you want a service that does everything - fast trains,
slow trains, a panoply of branches, all presumably sharing with other
services. That just is not feasible.

tom

--
I'm angry, but not Milk and Cheese angry. -- Mike Froggatt

Andrew Heenan wrote:

And even the convenience arguments are flawed. Crossrail does not *have* to
be an all-stopper;

No, but it's the only rational choice. The longer the overall journey,
the less the benefit from avoiding a change of trains. It makes sense to
use the cross-London lines for services it will benefit most - roughly,
those for which the slowness of an all-stations service is outweighed by
the time saving from not having to change.

In addition, we know that reductions in journey times just increase the
distances people will travel, after a few years to adapt, change jobs,
move house etc. A commuter line ought to be encouraging people to live
closer to work, not farther away, in the interest of avoiding
unnecessary energy use.

Colin McKenzie

--
No-one has ever proved that cycle helmets make cycling any safer at the
population level, and anyway cycling is about as safe per mile as walking.
Make an informed choice - visit www.cyclehelmets.org.

Graeme Wall wrote:
In message
Tom Anderson wrote:

On Wed, 3 Dec 2008, 1506 wrote:

On Dec 3, 10:02 am, Mr Thant
wrote:
On 3 Dec, 17:46, 1506 wrote:

I didn't think there were too many left in NYC. I can only recall one
short section in Manhattan. Do the other Boroughs have many Els left?
Brooklyn is chockablock with them, and I think most of the Subway
network in Queen's is elevated.

(also, I'd question whether you can build a true El with brick
viaducts, given the lack of space underneath them)
Point taken, although I wonder what options were available in the 1860s?
Piles of compacted commoners.


Like the Chiswick flyover you mean?

Must be a good bridge (Kipling)

--
Corporate society looks after everything. All it asks of anyone, all it
has ever asked of anyone, is that they do not interfere with management
decisions. -From “Rollerball”

Graeme Wall wrote:
In message
Roland Perry wrote:

In message , at 09:48:12 on Thu, 4
Dec 2008, Graeme Wall remarked:
Don't know if it still exists in the current economic situation, but
there used to be a lot of traffic between high tech firms in the Thames
Valley and places like Marconi at Chelmsford.
I think the main demise is that "places like Marconi" have almost ceased
to exist in Chelmsford!

So what does it do now to justify it's existance?

Though its new life as a dormitory began in a small way in the 1950s, it
is only now beginning to get big.

--
Corporate society looks after everything. All it asks of anyone, all it
has ever asked of anyone, is that they do not interfere with management
decisions. -From “Rollerball”

In message
Martin Edwards wrote:

Graeme Wall wrote:
In message
Tom Anderson wrote:

On Wed, 3 Dec 2008, 1506 wrote:

On Dec 3, 10:02 am, Mr Thant
wrote:
On 3 Dec, 17:46, 1506 wrote:

I didn't think there were too many left in NYC. I can only recall one
short section in Manhattan. Do the other Boroughs have many Els left?
Brooklyn is chockablock with them, and I think most of the Subway
network in Queen's is elevated.

(also, I'd question whether you can build a true El with brick
viaducts, given the lack of space underneath them)
Point taken, although I wonder what options were available in the 1860s?
Piles of compacted commoners.


Like the Chiswick flyover you mean?

Must be a good bridge (Kipling)


It's made of cake???

--
Graeme Wall
This address is not read, substitute trains for rail.
Transport Miscellany at http://www.greywall.demon.co.uk/rail/index.html