On 31 Dec, 21:40, Hertsman wrote:
On 31 Dec, 21:22, Peter Lawrence wrote:

I noticed yesterday, approaching S.P.I.L.L. from the north, that we were
one of two trains running side by side through the tunnel into the
station. *(All trains were terminating there.) * Can anyone explain how
this can happen?

From the Thamelink Programme website:

Signalling: The route across central London changes entirely. In 2011
there will be new crossovers to give First Capital Connect the
flexibility of running trains into either of the two Thameslink
platforms at St Pancras International, regardless of their direction
of travel. Could be this is now available for use!

From December 2011, signals will be installed closer together than at
present, like a metro system instead of approximately every 1km which
will allow trains to safely travel closer together, increasing
capacity.

From Easter 2012 there will be bi-directional signalling across the
entire core – from Kentish Town to Blackfriars and the bay platforms
at Blackfriars will be brought into use.

It has to be that the bi-directional signalling is in place. It can be
disconcerting to see it in operation, though. I remember when it was
first implemented south of Guildford, whereby southbound trains can
set off together through the tunnels, and it seemed most odd. For some
reason there, though, bi-directional running is only in the south-
bound direction. (I hesitate to use the conventional railway terms of
up and down because at Guildford, a southbound Portsmouth train is a
down train whilst a southbound Gatwick train is an up one.)

I noticed yesterday, approaching S.P.I.L.L. from the north, that we were
one of two trains running side by side through the tunnel into the
station. *(All trains were terminating there.) *



Bi-di west of SPILL has been in place for quite a while now.

Something like 12 months ?

ISTR the signalling was commissioned around about autumn 2009 and
allowed for in timetable from 12/2009. Or something like that.

Both A and B at SPILL are used at weekends, although things do not
seem fixed from one weekend to the next, it depends on what actual
work is taking place.

--
Nick

In message
,
D7666 writes
Both A and B at SPILL are used at weekends, although things do not
seem fixed from one weekend to the next, it depends on what actual
work is taking place.

Indeed. What needs to be changed are the signs at SPILL clearly
indicate the platforms for "Northbound" and "Southbound". This is very
misleading when both platforms are for northbound services, as happens
most evenings and weekends.

--
Clive Page

On 01/01/2011 13:56, Clive Page wrote:
In message
,
D7666 writes
Both A and B at SPILL are used at weekends, although things do not
seem fixed from one weekend to the next, it depends on what actual
work is taking place.

Thankyou. My surprise was not at the bi-directional working but that one
train could catch up with another when both (presumably) used the same
southbound platform at Kentish Town and the second one must wait for the
crossover points to be changed after the first one. Does the
bi-directional working extend as far north as Dock Junction and Kentish
Town?

Indeed. What needs to be changed are the signs at SPILL clearly indicate
the platforms for "Northbound" and "Southbound". This is very misleading
when both platforms are for northbound services, as happens most
evenings and weekends.

Agreed. Further, there are no signs above platform level at SPILL which
indicate intermediate stops so, if there is a choice of platform,
passengers have to memorise the timetable to decide which train meets
their needs.

On Jan 1, 6:17*pm, Peter Lawrence wrote:
On 01/01/2011 13:56, Clive Page wrote:

In message
,
D7666 writes
Both A and B at SPILL are used at weekends, although things do not
seem fixed from one weekend to the next, it depends on what actual
work is taking place.

Thankyou. My surprise was not at the bi-directional working but that one
train could catch up with another when both (presumably) used the same
southbound platform at Kentish Town and the second one must wait for the
crossover points to be changed after the first one. *Does the
bi-directional working extend as far north as Dock Junction and Kentish
Town?

Trains can run off of the up slow (as normal) into St Pancras and they
can also run off of the up fast, through P3 and then in the up
direction along the Down Slow which is what I suspect you saw. Coming
out both trains would need to run along the down slow for a short
period of time, the one using the up slow in the down direction would
have to wait for the train running down the down slow to clear into
platform 2 or 3 at Kentish Town first before crossing over onto the
down line. It is also possible that the overlap on the track circuits
could prevent the signal clearing until a train has cleared the
station or a time out has taken place. Not sure in this case.

Richard

On 01/01/2011 19:32, Fat richard wrote:
On Jan 1, 6:17 pm, Peter wrote:
On 01/01/2011 13:56, Clive Page wrote:

In message
,
writes
Both A and B at SPILL are used at weekends, although things do not
seem fixed from one weekend to the next, it depends on what actual
work is taking place.

Thankyou. My surprise was not at the bi-directional working but that one
train could catch up with another when both (presumably) used the same
southbound platform at Kentish Town and the second one must wait for the
crossover points to be changed after the first one. Does the
bi-directional working extend as far north as Dock Junction and Kentish
Town?

Trains can run off of the up slow (as normal) into St Pancras and they
can also run off of the up fast, through P3 and then in the up
direction along the Down Slow which is what I suspect you saw.

Thankyou, that explains it.

Coming
out both trains would need to run along the down slow for a short
period of time, the one using the up slow in the down direction would
have to wait for the train running down the down slow to clear into
platform 2 or 3 at Kentish Town first before crossing over onto the
down line. It is also possible that the overlap on the track circuits
could prevent the signal clearing until a train has cleared the
station or a time out has taken place. Not sure in this case.

Richard

On Sat, 1 Jan 2011 13:56:34 +0000, Clive Page wrote:

Indeed. What needs to be changed are the signs at SPILL clearly
indicate the platforms for "Northbound" and "Southbound". This is very
misleading when both platforms are for northbound services, as happens
most evenings and weekends.

There are no southbound trains?

--
jhk

On Jan 2, 9:23*pm, Jarle H Knudsen wrote:

most evenings and weekends.

There are no southbound trains?

Not at the times referred to no.

SB arrivals and NB departures only.

--
Nick

On Jan 1, 1:56*pm, Clive Page wrote:

Indeed. *What needs to be changed are the signs at SPILL clearly
indicate the platforms for "Northbound" and "Southbound". * This is very
misleading when both platforms are for northbound services, as happens
most evenings and weekends.


But is only temporary during the engineering works ...

.... and any passenger seeing those signs has actually already passed
the indicator displaying specific platform information ... there are
no other entrances on to the platforms than via the ground level
barrier line, and the indicators are right there.


--
Nick

In message
,
D7666 writes
... and any passenger seeing those signs has actually already passed
the indicator displaying specific platform information ... there are
no other entrances on to the platforms than via the ground level
barrier line, and the indicators are right there.

That's only true when the indicators are actually working (and often
they are not).


--
Clive Page