In message , at 23:40:28 on
Tue, 19 Jul 2005, Robert Woolley
remarked:
The crime scene is very close to the trailing crossover just south of
Kings Cross hence the closure.

There are no other crossovers between Arnos and Hyde Park Corner.

Why can't they run a "one train on the line" shuttle service on both the
tracks simultaneously? Over strategic sections: eg from Green Park to
Holborn and back. And Kings Cross to Finsbury Park and back.

Or is the reduced capacity that would offer actually worse than running
nothing at all?
--
Roland Perry

In article ,
Roland Perry wrote:
Or is the reduced capacity that would offer actually worse than running
nothing at all?

I suspect that demand would so far strip supply that the platforms would
be dangerously overcrowded.

isolating the power so that work around Kings X may be tricky.

--
Mike Bristow - really a very good driver

In message , at 07:14:16 on Wed,
20 Jul 2005, Mike Bristow remarked:
In article ,
Roland Perry wrote:
Or is the reduced capacity that would offer actually worse than running
nothing at all?

I suspect that demand would so far strip supply that the platforms would
be dangerously overcrowded.

I was suggesting fairly short runs, with one train in each tunnel. You'd
get about one every 10 minutes I suppose.

isolating the power so that work around Kings X may be tricky.

Just lift the rails for a short section south of the station.

But I agree that you'd have to see where the power feed was, and make
sure that was sufficient within the proposed schemes.
--
Roland Perry

In message , Roland
Perry writes
isolating the power so that work around Kings X may be tricky.

Just lift the rails for a short section south of the station.

But I agree that you'd have to see where the power feed was, and make
sure that was sufficient within the proposed schemes.
In the central section, a current section might only be a few hundred
yards long and is easily isolated by touching the telephone wires
together and laying down short circuiting bars in the section.
--
Clive

On Wed, 20 Jul 2005 07:52:12 +0100, Roland Perry
wrote:

In message , at 23:40:28 on
Tue, 19 Jul 2005, Robert Woolley
remarked:
The crime scene is very close to the trailing crossover just south of
Kings Cross hence the closure.

There are no other crossovers between Arnos and Hyde Park Corner.

Why can't they run a "one train on the line" shuttle service on both the
tracks simultaneously? Over strategic sections: eg from Green Park to
Holborn and back. And Kings Cross to Finsbury Park and back.

Or is the reduced capacity that would offer actually worse than running
nothing at all?

The frequency would be so low as to be almost useless - a train every
20-25 mins in each direction on each track at best. That analysis
ignores whether you could deal with the situation at Arnos Grove as not
every train could head south from there so some people would still have
to be placed onto replacement buses as the trains couldn't carry the
likely demand. You also have the issue of trains from each platform
going in each direction with the platform indicators and station signage
not configured to be able to cope with such an operation.

You would get massive issues at somewhere like Finsbury Park - what
platform would you go to and when for a northbound or southbound train
if both Picc tunnels ran in both directions? The potential for people
interchanging to get crushed in the narrow connecting corridors would be
too great and the risk to staff of assaults from angry and confused
passengers would be an issue too. As a side issue thank goodness it is
not the football season at present - quite how match crowds for Arsenal
will be managed I dread to think if the Picc remains out of action for a
long while.

You'd also run into issues about evacuation in the event of emergencies
where such a different method of operation could create risks and which
would require additional mitigation / controls over and above existing
procedures. All of that would have to be developed, approved and rolled
out before operation could take place.

It is far better to get people away from closed sections of line and on
to alternatives that are able to provide a robust level of service.
--
Paul C


Admits to working for London Underground!

In message , at 19:11:48 on
Wed, 20 Jul 2005, Paul Corfield remarked:

The crime scene is very close to the trailing crossover just south of
Kings Cross hence the closure.

There are no other crossovers between Arnos and Hyde Park Corner.

Why can't they run a "one train on the line" shuttle service on both the
tracks simultaneously? Over strategic sections: eg from Green Park to
Holborn and back. And Kings Cross to Finsbury Park and back.

Or is the reduced capacity that would offer actually worse than running
nothing at all?

The frequency would be so low as to be almost useless - a train every
20-25 mins in each direction on each track at best.

Green Park to Holborn is only four stops. Say 2 minutes each. And 2
minutes to reverse. These are worst-case. That gives you a complete
round trip in 20 minutes, and with two tunnels a 10 minute frequency.

That analysis ignores whether you could deal with the situation at
Arnos Grove as not every train could head south from there so some
people would still have to be placed onto replacement buses as the
trains couldn't carry the likely demand.

I'm not proposing anything changes at Arnos Grove.

You also have the issue of trains from each platform
going in each direction with the platform indicators and station signage
not configured to be able to cope with such an operation.

Have someone at each station operating a sign that says which (of the
two) platform the next train each way is expected. Green Park to Holborn
would need five people.

You would get massive issues at somewhere like Finsbury Park - what
platform would you go to and when for a northbound or southbound train
if both Picc tunnels ran in both directions?

You'd need to use some intelligence to set up a suitable system. Why are
you so defeatist?

quite how match crowds for Arsenal will be managed I dread to think if
the Picc remains out of action for a long while.

You'd probably need to close my system for the duration of football
matches. Yes, I can be defeatist too.

It is far better to get people away from closed sections of line and on
to alternatives that are able to provide a robust level of service.

If the alternate service is that good, why have the original service? (I
detect people asking this question about the Circle Line...)
--
Roland Perry

On Wed, 20 Jul 2005 19:52:27 +0100, Roland Perry
wrote:

[snip]

You'd need to use some intelligence to set up a suitable system. Why are
you so defeatist?

Roland - I was trying to give a flavour of the issues involved. I am not
being defeatist at all.

Whatever system is designed has to be easy for the public to understand.
Having watched the utter confusion at Kings Cross when the first train
on a Sunday arrived from Heathrow - this reverses as I am sure you know
- I am convinced a more intensive proposition would not work. People on
the arriving train were non plussed as to what to do for stations beyond
KX on the Picc Line and I also watched people trying to get onto the
normal westbound platform, which is locked up at that time of day, who
then refused to believe suggestions from me and station staff that the
train on the "wrong" platform is really the train they want. Multiply
that a few thousand fold and you have a mess.

I make my contribution to this group voluntarily to try to help people
understand. I really don't need criticism for trying to be helpful.
--
Paul C


Admits to working for London Underground!

In message , at 21:27:03 on
Wed, 20 Jul 2005, Paul Corfield remarked:
On Wed, 20 Jul 2005 19:52:27 +0100, Roland Perry
wrote:

[snip]

You'd need to use some intelligence to set up a suitable system. Why are
you so defeatist?

Roland - I was trying to give a flavour of the issues involved. I am not
being defeatist at all.

Whatever system is designed has to be easy for the public to understand.

I agree. But I think the public are more adaptable.

I make my contribution to this group voluntarily to try to help people
understand. I really don't need criticism for trying to be helpful.

Me too.
--
Roland Perry

In article , Roland
Perry writes
Or is the reduced capacity that would offer actually worse than running
nothing at all?

Quite possibly.

The Waterloo & City Line (IIRC) has alternative timetables for use if
one or two of the trains fail, but closes if three trains are out of
action because overcrowding would make things dangerous.

--
Clive D.W. Feather | Home:
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