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Old June 15th 09, 11:34 AM posted to uk.railway,uk.transport.london
Andy Andy is offline
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First recorded activity at LondonBanter: Jul 2006
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Default LU strike and possible knock-on effects on NR / LO services [was:Tube strike]

On 13 June, 20:50, MIG wrote:
On 9 June, 18:32, wrote:





On Jun 9, 4:58*pm, MIG wrote:


On 9 June, 16:41, wrote:


On 9 June, 14:49, MIG wrote:


On 9 June, 14:40, wrote:


On 9 June, 00:38, asdf wrote:


On Sat, 6 Jun 2009 10:20:56 -0700 (PDT), wrote:
Oh ang on though, if they used platform 1 at HotH, I think there may
be a crossover. *Not sure if it isn't just a track crossing to/from
the Metropolitan or if it leads to/from the up Chiltern track as well.


I can't remember if this crossover can be used from Up departures from
Platform 1 at Harrow. My memory tells me that there is no signal for
this route. What I can't remember is if the crossover from the NB Fast
to the Platform 1 just passes over the intervening Up line or whether
there is pointwork in the Up line allowing access.


There isn't pointwork - it's one of those things that I think is
referred to as a diamond crossing.


Thanks, I though it probably was, but couldn't remember.


It can't be that simple though, because it has to allow for
Metropolitan trains in both directions, doesn't it? *So there must be
something from the up Chiltern to the Met as well as the diamond from
the Met to the down Chiltern, even if nothing from platform 1 to the
up Chiltern?


Platform 1 is only accessible from the Down Chiltern and the NB Met
fast, via the diamond crossing, heading north (to the NB Met fast),
with no access heading south without a shunt. Platform 2 only has
access to the Up Chiltern, heading south from the SB Met fast, or the
NB Met fast heading north via the trailing crossover. There is no
access to other Met line tracks (i.e. the both southbound, NB slow or
the Uxbridge lines). Met line trains only use Platform 1 heading
north, from the NB fast or platform 2 reversing from SB to NB. There
are no other Met line possibilities, with the current layout.- Hide quoted text -


- Show quoted text -


Ah right, so you can't take the Met south through platform 2, I think
you are saying, and it's electricked only for reversing back north.
That seems a bit unbalanced given that you can go north through
platform 1, but if that's the way it is ... *Hard to tell from
diagrams.


That's right. To go south to the Met from platform 2 would require
crossing both northbound tracks, so all crossing moves happen at
Harrow North Junction, where only the NB slow is crossed. On the other
hand, using platform 1 for NB Met fast services takes only takes them
across the SB Chiltern and gives extra platform capacity in the
evening peak.-


A bit late to go back to this one, but I got round to checking the
right Quails. *The Southern (most up-to-date) edition corresponds
exactly to what you say, with the electrification not even extending
from platform 2 as far back as the diamond.

But the Western edition is very different, showing more
electrification and difficult to interpret whether there's a
crossover, because of the colours not quite lining up. *I wonder if
there has been a change in recent years or one there was a mistake?


There were quite a few mistakes introduced when Quail switched to
colour and the Western version is definately wrong. I don't think that
there have been any changes to the electrification on the 'Chiltern'
platforms for many years, possibily not since the 1960s.