Steve Fitzgerald ] wrote:

writes

. Potters Bar might be a better location, but their trains don't stop
there yet. If they, or their successors, ever do start stopping their
trains there, it might be worth considering extending the Jubilee Line
there. But it's not going to become as important a station as Watford
Junction any time in the forseeable future.

Wouldn't it be easier to extend the Piccadilly there in that eventuality
as it's just up the road from Cockfosters?

Yes it would. However the Piccadilly does not venture very far from the
GN, so the benefits would be much lower.

--
Aidan Stanger
http://www.bettercrossrail.co.uk

"Aidan Stanger" wrote in message
...
Steve Fitzgerald ] wrote:

writes

. Potters Bar might be a better location, but their trains don't stop
there yet. If they, or their successors, ever do start stopping their
trains there, it might be worth considering extending the Jubilee Line
there. But it's not going to become as important a station as Watford
Junction any time in the forseeable future.

Wouldn't it be easier to extend the Piccadilly there in that eventuality
as it's just up the road from Cockfosters?

Yes it would. However the Piccadilly does not venture very far from the
GN, so the benefits would be much lower.

As somebody who grew up in Potters Bar and knows the area reasonably well,
there is also the small question of engineering difficulties and overall
cost. It would need some major earthworks or, more appropriately, tunnelling
(there is the small geographical feature of Stag Hill to contend with.) This
would be a hugely expensive project for little economic gain. It also falls
outside the TfL area. You only have to look at the problems faced by the
rather more practical proposal to join up the Watford branch of the
Metropolitan to Watford Junction, along the former Croxley Green track bed
to see the difficulties that scheme has faced, not least through the
TfL/Hertfordshire CC interface and the different funding regimes.

I think this discussion has grown out of all proportion. In the off
peak when things are not quite running to time, the line controllers
will often just send the odd train in 4 to MHE, which is in effect the
same service as a shuttle (15 mins). The shuttles are set up currently
in times of severe disruption, but from what I can see, I don't quite
grasp the reason for the mass debate?

Whats the current interval off peak anyhow?

The other flaw in the main arguments are a "through service", a
"through service" to what exactly? Camden? Change. Bank? Change.
Euston? Change. The Tube is unlike the rest of the railway where
changes can be painstaking and frustrating. The tube network is a whole
series of walks, transfers and interchanges. So a few dozen people at
Finchley Central are left waiting an extra 2 minutes for a MHE train,
whats the major deal?

The notion of reducing train lengths incidentally to save costs is
ridiculous in this instance because there would have to be customised
rolling stock for a branch line. Commonality of fleet breeds reliable
trains, fact.

Anyone know whether the change is borne from TfL or a TubeLines
infastructure related cost?

Ian

wrote in message
oups.com...

Whats the current interval off peak anyhow?

Between 1996 and 1998, MHE had a train every 12-15 minutes whenever the line
was open. The frequency depended not on demand but on whole number intervals
of the mainline headway... so at the time of night when the mainline dropped
from 5 minute headways to 6, the MHE frequency went up from 15 to 12. See
http://www.geocities.com/Athens/Acro....html#Northern

wrote:

I think this discussion has grown out of all proportion. In the off
peak when things are not quite running to time, the line controllers
will often just send the odd train in 4 to MHE, which is in effect the
same service as a shuttle (15 mins). The shuttles are set up currently
in times of severe disruption, but from what I can see, I don't quite
grasp the reason for the mass debate?

Introducing a shuttle service is a good idea, but the way they're
planning to do it isn't, and has triggered speculation about whether
they're running the service down prior to closure.

Whats the current interval off peak anyhow?

The other flaw in the main arguments are a "through service", a
"through service" to what exactly? Camden? Change. Bank? Change.
Euston? Change.

Only the second of those examples would require a change.

The Tube is unlike the rest of the railway where
changes can be painstaking and frustrating. The tube network is a whole
series of walks, transfers and interchanges. So a few dozen people at
Finchley Central are left waiting an extra 2 minutes for a MHE train,
whats the major deal?

The big deal is that they're worsening the service, whereas it would be
so easy for them to improve the service.

The notion of reducing train lengths incidentally to save costs is
ridiculous in this instance because there would have to be customised
rolling stock for a branch line. Commonality of fleet breeds reliable
trains, fact.

The notion that it is a ridiculous notion is itself ridiculous! Firstly
it's commonality of modular components and equipment layout that gives a
reliability advantage - not how far the back cab is from the front cab!

Secondly, the rest of the fleet's big enough to gain a commonality
advantage. Having one train different is unlikely to impact on the
reliability of the rest of the fleet, even if the reliability of the
train that's different is adversely affected.

And thirdly, shorter trains are cheaper to maintain because there's less
of them to maintain! Supposing a 2 car train was sufficiently different
from the rest of the fleet that the maintenance cost per car km was
doubled. That still leaves you ahead of where you'd be if you ran a
6 car train.

Anyone know whether the change is borne from TfL or a TubeLines
infastructure related cost?

Not for certain, but it's more likely to be TfL.

--
Aidan Stanger
http://www.bettercrossrail.co.uk

In article .com,
writes
The other flaw in the main arguments are a "through service", a
"through service" to what exactly? Camden? Change. Bank? Change.
Euston? Change.

The current through service is to Morden or Kennington.

The notion of reducing train lengths incidentally to save costs is
ridiculous in this instance because there would have to be customised
rolling stock for a branch line.

No, there wouldn't. The Northern Line trains are 3-car units, coupled in
pairs to make 6-car trains. You could run a single unit as the shuttle.

This whole thing is *just* like the Chesham branch: shuttle off-peak,
through trains in the peak, shuttle being a single unit and all other
trains on the line being pairs.

--
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:

"Clive D. W. Feather" wrote in message
...
In article .com,
writes
The other flaw in the main arguments are a "through service", a
"through service" to what exactly? Camden? Change. Bank? Change.
Euston? Change.

The current through service is to Morden or Kennington.

The notion of reducing train lengths incidentally to save costs is
ridiculous in this instance because there would have to be customised
rolling stock for a branch line.

No, there wouldn't. The Northern Line trains are 3-car units, coupled in
pairs to make 6-car trains. You could run a single unit as the shuttle.

This whole thing is *just* like the Chesham branch: shuttle off-peak,
through trains in the peak, shuttle being a single unit and all other
trains on the line being pairs.

Although the Northern Line trains are made up of two 3-car units, they do
not have cabs at both ends so it would not be possible to run a 3 car train
of 95 stock.

Peter Smyth

The other flaw in the main arguments are a "through service", a
"through service" to what exactly? Camden? Change. Bank? Change.
Euston? Change.

The current through service is to Morden or Kennington.

The notion of reducing train lengths incidentally to save costs is
ridiculous in this instance because there would have to be customised
rolling stock for a branch line.

No, there wouldn't. The Northern Line trains are 3-car units, coupled
in pairs to make 6-car trains. You could run a single unit as the
shuttle.

Except the trains are formed with UNDMs at the inner ends of the units
and therefore have no driving cabs (Apart from the shunting panel, of
course). 95 stock doesn't have any double ended 3 car units.
--
Steve Fitzgerald has now left the building.
You will find him in London's Docklands, E16, UK
(please use the reply to address for email)

Steve Fitzgerald wrote:
The other flaw in the main arguments are a "through service", a
"through service" to what exactly? Camden? Change. Bank? Change.
Euston? Change.

The current through service is to Morden or Kennington.

The notion of reducing train lengths incidentally to save costs is
ridiculous in this instance because there would have to be customised
rolling stock for a branch line.

No, there wouldn't. The Northern Line trains are 3-car units, coupled
in pairs to make 6-car trains. You could run a single unit as the
shuttle.

Except the trains are formed with UNDMs at the inner ends of the units
and therefore have no driving cabs (Apart from the shunting panel, of
course). 95 stock doesn't have any double ended 3 car units.

How easy/difficult would it be to create a double-ended unit using
existing cars?

--
John Band
john at johnband dot org
www.johnband.org

In message .com, John
B writes
Except the trains are formed with UNDMs at the inner ends of the units
and therefore have no driving cabs (Apart from the shunting panel, of
course). 95 stock doesn't have any double ended 3 car units.

How easy/difficult would it be to create a double-ended unit using
existing cars?

I'm not that familiar with 95 stock but on 73s (which I am more familiar
with) it would not be even considered. For a start you would lose a
full train in the process as you would need the driving cab from each
end (2 units) to make up your little train. Then you would leave the
other 3 cars sat around taking space up that now couldn't be used.

Tube stock is formed into fixed units (either 3 or 4 car) with
semi-permanent couplers within the unit and the electrics and other
jumpers hard wired as they are designed to be only split in the
workshops, and therefore can't be re-marshalled on a whim. Equipment is
also spread throughout the train (ie, the compressors are actually in
the trailers) as there is a shortage of space. It's highly likely that
the cars marshalled into this little train would have to have some sort
of wiring modifications and no doubt the software would have to be
rewritten and then debugged as the train currently expects to find 6
cars out there.

Another issue here is that the trains have everything duplicated for
backup in case of problems. In the case of our 3 car 73 stock for
example, (the ones with two cabs, known as double ended units) this
means that the trailers have been fitted with 2 compressors to comply
with this and thus can operate as a 3 car unit, so no doubt any 95s used
would have to be similarly modified. Now, before anyone suggests that
it might be a good wheeze to steal a 3 car double ended 73TS for this
mythical exercise, I should also add that there are restrictions where
various trains can go; and due to the fitment of static converters at
refurbishment, 73TS is now restricted to the Piccadilly and other
limited excursions where appropriate signalling immunisation has taken
place.

Then you have another problem in that you would now have a unique train
(so, what happens when it needs serious work done, do you have a second
short spare to maintain the service?). If you do have service problems,
that train then couldn't be used anywhere else to maybe fill a gap in
the service and then bring in a later train in to recover the MHE
service. Allocations of trains to workings at depots (yes, each working
is allocated a specific train at the start of the day) would be
complicated as you have different types of train involved and it can't
be rotated to even out the mileage either.

These are just a few random thoughts why I think it would never happen.
--
Steve Fitzgerald has now left the building.
You will find him in London's Docklands, E16, UK
(please use the reply to address for email)