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.