Another W&C Closure?
 

On 18 Mar, 22:55, "Richard J." wrote:
Anyway, where does it say that S stock floors will be at tube stock height?

There's a guy on the District Dave boards called pjrb who does a
pretty convincing job of claiming to be one of the guys working on the
S stock.

He mentions low floors here, although on reflection, he doesn't
mention tube height:
http://districtdave.proboards39.com/...e=1#1158424908

U

Route Swap (was: Another W&C Closure?)
 

On Mar 18, 10:09 pm, "Recliner" wrote:
How about Ealing Common, where the same platforms serve both Picc and
District stock, or Acton Town where Picc trains frequently use the
District platforms? Or Rayner's Lane to Uxbridge?

Simple - swap the Picc and District services to Uxbridge and Ealing
Broadway.

Except it isn't that simple; it's actually a hoary old chestnut that
has been kicking around the halls of 55 Broadway for quite a while,
and is not likely to be seriously considered until either T5 finally
opens and the Picc services to Uxbridge need to be reduced further to
maintain loadings on the Heathrow branch, or when the S stock arrives
in sufficient numbers to allow Uxbridge to finally be served
adequately in terms of train availability (how an enhanced Uxbridge
service gets through Earl's Court on top of the existing services to
Richmond, Wimbledon and Olympia is a whole 'nother matter!)

Another W&C Closure?
 

On Mar 19, 12:57 pm, "Mr Thant"
wrote:
There's a guy on the District Dave boards called pjrb who does a
pretty convincing job of claiming to be one of the guys working on the
S stock.

I would imagine so, seeing as how he is actually one of the people in
charge of the project...

Another W&C Closure?
 

In article , David of Broadway
writes
Yes, that occurred to me after posting. But do Piccadilly line trains
really have to use the side tracks? I realize that doing so can reduce
delays for eastbound passengers getting off at Acton Town, but it
doesn't actually speed up train service much, does it? One train still
has to wait for the other before leaving the station.

Actually, it can help because of the longer headways needed at stations.
Put simply, when you work out the numbers you find that the minimum
possible time between trains is longer at stations than between them.
With two platforms you can negate this to some extent because one train
can be running in to the station with the previous one still departing;
with one platform, you can't let the second train in until the first has
cleared the overlap.

Admittedly, in this case you then run into the bottleneck again at
Hammersmith, but having the lower headways at Acton gives you more
robustness.

It also helps with the District. Suppose that an eastbound train from
Heathrow is in the Piccadilly platform, with a District train from
Ealing Broadway behind a Piccadilly from Uxbridge. If the latter can get
into the station before the ex-Heathrow has left, even though it blocks
the District's platform, the latter still gets through earlier.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

Another W&C Closure?
 

On Tue, 20 Mar 2007 12:34:07 +0000, Clive D. W. Feather wrote:

Yes, that occurred to me after posting. But do Piccadilly line trains
really have to use the side tracks? I realize that doing so can reduce
delays for eastbound passengers getting off at Acton Town, but it
doesn't actually speed up train service much, does it? One train still
has to wait for the other before leaving the station.

Actually, it can help because of the longer headways needed at stations.
Put simply, when you work out the numbers you find that the minimum
possible time between trains is longer at stations than between them.
With two platforms you can negate this to some extent because one train
can be running in to the station with the previous one still departing;
with one platform, you can't let the second train in until the first has
cleared the overlap.

Admittedly, in this case you then run into the bottleneck again at
Hammersmith, but having the lower headways at Acton gives you more
robustness.

It's more significant than that - driver changes take place at Acton,
which means dwell time there is often longer than at Hammersmith
(etc).

Route Swap (was: Another W&C Closure?)
 

On 19 Mar 2007 08:12:01 -0700, TheOneKEA wrote:

How about Ealing Common, where the same platforms serve both Picc and
District stock, or Acton Town where Picc trains frequently use the
District platforms? Or Rayner's Lane to Uxbridge?

Simple - swap the Picc and District services to Uxbridge and Ealing
Broadway.

Except it isn't that simple;

And wouldn't solve the problem at Ealing Common anyway.

Another W&C Closure?
 

On 18 Mar, 21:48, "
wrote:
On 18 Mar, 19:02, David of Broadway
wrote:


Don't forget that one day the Bakerloo will take over the whole route
to Watford.



London Rail are talking about it, but in relality it is in the region
of 2025 before it will happen.

Ian

Another W&C Closure?
 

On Sun, 18 Mar 2007, Jack Taylor wrote:

Richard J. wrote:

But until you do, you can't use the new stock! To accommodate the two
heights at a single platform, the platform level needs to be a
compromise. If it's level with either stock, the other stock would be
unreasonably low or high. Anyway, where does it say that S stock floors
will be at tube stock height? I don't believe that's true.

Neither do I. How would that work on the Metropolitan, where all platforms
are "normal" height and platforms from Harrow northwards are shared with
standard gauge overground stock (Chiltern)?

Kneeling suspension?

tom

--
Destroy - kill all hippies.

Another W&C Closure?
 

asdf wrote:
On Tue, 20 Mar 2007 12:34:07 +0000, Clive D. W. Feather wrote:

Yes, that occurred to me after posting. But do Piccadilly line
trains really have to use the side tracks? I realize that doing
so can reduce delays for eastbound passengers getting off at
Acton Town, but it doesn't actually speed up train service much,
does it? One train still has to wait for the other before
leaving the station.

Actually, it can help because of the longer headways needed at
stations. Put simply, when you work out the numbers you find that
the minimum possible time between trains is longer at stations
than between them. With two platforms you can negate this to some
extent because one train can be running in to the station with the
previous one still departing; with one platform, you can't let the
second train in until the first has cleared the overlap.

Admittedly, in this case you then run into the bottleneck again at
Hammersmith, but having the lower headways at Acton gives you more
robustness.

It's more significant than that - driver changes take place at
Acton, which means dwell time there is often longer than at
Hammersmith (etc).

Two comments on that:

1. If driver changes were properly managed, there would be no need for
longer dwell times. Some of the current changes are decidedly
leisurely, even when the new driver is already on the platform when the
train arrives.

2. In my experience, full use of the platform capacity isn't always
made, causing westbound trains to crawl through Turnham Green in the
queue to enter Acton Town. It's ludicrous that a station with extra
platform capacity should be a bottleneck.

--
Richard J.
(to e-mail me, swap uk and yon in address)

Another W&C Closure?
 

On 20 Mar, 16:50, "Ian Rivett" wrote:

Don't forget that one day the Bakerloo will take over the whole route
to Watford.

London Rail are talking about it, but in relality it is in the region
of 2025 before it will happen.


Based on what? It's hardly a project of Crossrail complexity...

--
John Band
john at johnband dot org
www.johnband.org