I'm not sure when this started happening, but trains were running round
the loop again yesterday. Signs inside the train I was on had not yet
been updated.
--
Roland Perry

On Thu, 21 Sep 2006 15:35:28 +0100, Roland Perry
wrote in :
I'm not sure when this started happening, but trains were running round
the loop again yesterday. Signs inside the train I was on had not yet
been updated.

http://www.tfl.gov.uk/tfl/press-cent...t.asp?prID=895

--
Ivan Reid, Electronic & Computer Engineering, ___ CMS Collaboration,
Brunel University. ] Room 40-1-B12, CERN

Dr Ivan D. Reid wrote:
http://www.tfl.gov.uk/tfl/press-cent...t.asp?prID=895

Incidentally, how is the line going to look once T5 is opened? Is it
still going to be a loop, with three stations (T4, T5, T123 in that
order from central London), or is the line going to split after Hatton
Cross with some trains going to T4 and some to T123 & T5?

Patrick

wrote:

Dr Ivan D. Reid wrote:
http://www.tfl.gov.uk/tfl/press-cent...t.asp?prID=895

Incidentally, how is the line going to look once T5 is opened? Is it
still going to be a loop, with three stations (T4, T5, T123 in that
order from central London), or is the line going to split after Hatton
Cross with some trains going to T4 and some to T123 & T5?

Patrick

It's the latter AIUI - i.e. trains will run either:

(1) Hatton Cross - T4 - T123 - Hatton Cross in the loop
or
(2) Hatton Cross - T123 - T5 where they'll terminate and then reverse.

The service will be split half/half. Those going to T123 will find
themselves there quicker on a train that goes to T5, as they won't have
to go round the loop. In practice I guess the time penalty for being on
a T4 loop train won't be that great so maybe just a few savvy
passengers with light or no luggage will hop between trains to take
advantage of this.

I've read that the T5 station will be staffed by BAA personnel, I guess
because they've entirely paid for the new Picadilly line link and
station to T5. I wonder how well they'll do in dispensing good advice
about public transport in London, and explaining the advantages of the
Oyster card and various other tickets and selling them to punters.

On 22 Sep 2006 01:34:21 -0700, Mizter T wrote:

It's the latter AIUI - i.e. trains will run either:

(1) Hatton Cross - T4 - T123 - Hatton Cross in the loop
or
(2) Hatton Cross - T123 - T5 where they'll terminate and then reverse.

The service will be split half/half.

Isn't it 2/3 T5 vs 1/3 T4? Or perhaps I'm imagining that.

Those going to T123 will find
themselves there quicker on a train that goes to T5, as they won't have
to go round the loop. In practice I guess the time penalty for being on
a T4 loop train won't be that great so maybe just a few savvy
passengers with light or no luggage will hop between trains to take
advantage of this.

I remember reading that T4 trains will have a layover in the platform
at T4 station, so for T123 it would probably be quicker to wait 5
minutes and catch the following T5 train.

ISTM that it would be better to reverse the direction that trains go
around the loop (and still lay over at T4). This would avoid the above
problem, and effectively increase the service frequency to T123 by 50%
(at the expense of effectively reducing it *from* T123, but in that
direction people aren't under time pressure to catch flights).

Slightly more radically, they could even close part of the loop,
running trains either CL-HX-T123-T4-T123-HX-CL, or CL-HX-T4-HX-CL
(where CL = Central London and HX = Hatton Cross). This would simplify
the line map and service pattern.

asdf wrote:

ISTM that it would be better to reverse the direction that trains go
around the loop (and still lay over at T4). This would avoid the above
problem, and effectively increase the service frequency to T123 by 50%
(at the expense of effectively reducing it *from* T123, but in that
direction people aren't under time pressure to catch flights).

Slightly more radically, they could even close part of the loop,
running trains either CL-HX-T123-T4-T123-HX-CL, or CL-HX-T4-HX-CL
(where CL = Central London and HX = Hatton Cross). This would simplify
the line map and service pattern.

They should shut Terminal 4 (station and terminal) until T1, T2, T3 and T5
are all operating to capacity, which will be years away.

In article , asdf
writes
It's the latter AIUI - i.e. trains will run either:
(1) Hatton Cross - T4 - T123 - Hatton Cross in the loop
or
(2) Hatton Cross - T123 - T5 where they'll terminate and then reverse.

That's forced by the physical layout:

T5 ---------*-- T123 ---------------* HX ----- London
/ /
| /
\ /
\-------- T4 -------/

ISTM that it would be better to reverse the direction that trains go
around the loop (and still lay over at T4).

If you do that then London-bound trains will have to cross the westbound
line on the level, putting constraints on operations. Anyway, I don't
think that there's room west of Hatton Cross for a crossover to the
eastbound track (the junction is officially 90m from the mid-point of
the station, and a crossover requires at least 40m). So now you're
talking major reconstruction as well as resignalling the loop (which is
signalled one-way only).

Slightly more radically, they could even close part of the loop,
running trains either CL-HX-T123-T4-T123-HX-CL, or CL-HX-T4-HX-CL
(where CL = Central London and HX = Hatton Cross). This would simplify
the line map and service pattern.

The latter has the above problem. The former has the problem that the
single line between T3 and T4 puts heavy constraints on how frequent the
trains can be. Probably 3tph would be the limit.

[Memory says this was covered in Underground News recently.]

--
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:

asdf wrote:

On 22 Sep 2006 01:34:21 -0700, Mizter T wrote:

It's the latter AIUI - i.e. trains will run either:

(1) Hatton Cross - T4 - T123 - Hatton Cross in the loop
or
(2) Hatton Cross - T123 - T5 where they'll terminate and then reverse.

The service will be split half/half.

Isn't it 2/3 T5 vs 1/3 T4? Or perhaps I'm imagining that.

No you're not imagining that - my assertion that the service will be
split half/half was wrong - it will indeed be two-thirds to T5 (10 tph)
and one-third to the T4 loop (5tph) according to one of utl's favourite
reference sources...

http://www.alwaystouchout.com/project/6

This makes sense as Terminal 5 is a big beast and will serve far more
passengers than T4 (though I don't have the actual numbers to hand).


Those going to T123 will find
themselves there quicker on a train that goes to T5, as they won't have
to go round the loop. In practice I guess the time penalty for being on
a T4 loop train won't be that great so maybe just a few savvy
passengers with light or no luggage will hop between trains to take
advantage of this.

I remember reading that T4 trains will have a layover in the platform
at T4 station, so for T123 it would probably be quicker to wait 5
minutes and catch the following T5 train.

The alwaystouchout page confirms that trains will lay over at T4. Given
the through trains going to and coming from the T5 terminus then it
won't be possible for trains to lay over at T123 anymore. It would
indeed therefore seem that T4 loop trains will be less desirable for
those going to T123. The layover period isn't that long but nontheless
I can imagine a train load of passengers anxiously asking staff why
they're stuck at T4 when they want to be at T123.

I don't know much about layovers on the tube, but it seems it would be
preferable if it were kept at T4 for as short a period as possible -
i.e. a quick change of driver (and perhaps a rapid litter blitz) before
the train continued on it's way. Trains could be held at T123 for a
short while to maintain proper service spacing (can't remember the
right term!) on the westbound Piccadilly line.

On Thu, 21 Sep 2006 15:35:28 +0100, Roland Perry wrote:

I'm not sure when this started happening, but trains were running round
the loop again yesterday. Signs inside the train I was on had not yet
been updated.

New line diagrams are appearing on Piccadilly Line trains, showing the
Heathrow loop again (replacing the previous ones which only showed the
replacement bus service).

As expected, they also show Sudbury Hill as an interchange for Sudbury
Hill Harrow.

The only other change I could see is that Hounslow West carries a note
that it is "step-free for wheelchair users only". The mind boggles...

asdf wrote:

The only other change I could see is that Hounslow West carries a note
that it is "step-free for wheelchair users only". The mind boggles...

There is a wheelchair lift which cannot be used by a standing person. I
would imagine it used to be a luggage lift, from the days when Hounslow West
was the airport stop.