Why do the drivers have to manually apply the pneumatics? Is it because the
train is in danger of overshooting the mark?

"asdf" wrote in message
...
On Sat, 19 Jan 2008 10:13:13 -0800 (PST), Mizter T wrote:

I'm getting on a bit (brings out violin) and my back doesn't like all
the excitement of the unplanned roller coaster ride the Victoria Line
can be.

Roll on the invention of inertial dampers :-)

Fair enough, I see your point - and yes, I suppose the Victoria line
can be a bit jerky. Perhaps the new stock on the upgraded line will
manage to do the job in a smoother manner, without sacrificing the
speed.

That seems perfectly possible - they could lower the rate of change of
deceleration, without significantly sacrificing the magnitude of the
deceleration.

I'm assuming that 67 stock be manually operated to speed, say on manual
coded? I can recall a couple of occasions where it felt like the driver was
fanning the brakes.

Also, is there a time when drivers are required to manually operate their
trains, besides going into depots and sidings?

"Paul Corfield" wrote in message
...
On Sat, 19 Jan 2008 21:41 +0000 (GMT Standard Time),
(Colin Rosenstiel) wrote:

In article ,
(Edward Cowling London UK) wrote:

[Victoria line]

Say what you like, but the trains always felt safer and seemed to
run better when they had a driver and a guard.

The Victoria Line has never had any other driving system than the one it
has today. So it's hard to make sense of your remarks. It is designed for
higher speeds than older lines so greater acceleration and braking is to
be expected.

Absolutely right in that it has always been automatic so the comparative
comment is wrong. However the thread has set me thinking and I believe
that there was a fairly recent change to the control system to remove
coasting and allow more accelerated running between stations. Given the
trains and the control system are near the end of their life there *may*
be some deterioration in performance when asset age and the removal of
coasting are combined.

Still the new trains will certainly accelerate and brake much more
quickly so I think it will definitely be a case of "hang on tight".
Part of me is looking forward to a faster and hopefully reliable journey
but I will miss 67 stock given the years I've been using it.

--
Paul C


Admits to working for London Underground!

On Sun, 20 Jan 2008 10:48:33 GMT, wrote:


"Paul Corfield" wrote in message
.. .
On Sat, 19 Jan 2008 21:41 +0000 (GMT Standard Time),
(Colin Rosenstiel) wrote:

In article ,
(Edward Cowling London UK) wrote:

[Victoria line]

Say what you like, but the trains always felt safer and seemed to
run better when they had a driver and a guard.

The Victoria Line has never had any other driving system than the one it
has today. So it's hard to make sense of your remarks. It is designed for
higher speeds than older lines so greater acceleration and braking is to
be expected.

Absolutely right in that it has always been automatic so the comparative
comment is wrong. However the thread has set me thinking and I believe
that there was a fairly recent change to the control system to remove
coasting and allow more accelerated running between stations. Given the
trains and the control system are near the end of their life there *may*
be some deterioration in performance when asset age and the removal of
coasting are combined.

Still the new trains will certainly accelerate and brake much more
quickly so I think it will definitely be a case of "hang on tight".
Part of me is looking forward to a faster and hopefully reliable journey
but I will miss 67 stock given the years I've been using it.

I'm assuming that 67 stock be manually operated to speed, say on manual
coded? I can recall a couple of occasions where it felt like the driver was
fanning the brakes.

Also, is there a time when drivers are required to manually operate their
trains, besides going into depots and sidings?

Yes 67 stock can be manually driven but only at low speeds - can't
remember the maximum but it's very slow compared to auto operation.

The only time drivers will drive in service is if there is a signalling
problem but "coded manual" is possible. This usually results in a crawl
and the driver having the "fan the brakes" as you describe. I haven't
experienced this operation for a long time so I'm not sure if they would
still use this practice or just simply suspend the service and allow
technicians in to do the fix.
--
Paul C


Admits to working for London Underground!

On Jan 20, 4:23*am, James Farrar wrote:
On Sat, 19 Jan 2008 20:09:35 +0000, asdf
wrote:





On Sat, 19 Jan 2008 19:24:58 +0000, Tom Anderson wrote:

Fair enough, I see your point - and yes, I suppose the Victoria line
can be a bit jerky. Perhaps the new stock on the upgraded line will
manage to do the job in a smoother manner, without sacrificing the
speed.

That seems perfectly possible - they could lower the rate of change of
deceleration, without significantly sacrificing the magnitude of the
deceleration.

You beat me to it! The rate of change of acceleration [1] is known as
'jerk rate',

[1] The fourth derivative of position with respect to time - fourth!

Third, surely?

"In the fall of 1972 President Nixon announced that the rate of
increase of inflation was decreasing. This was the first time that a
sitting president used the third derivative to advance his case for
reelection." - Hugo Rossi, Mathmetician.-

Many years ago a BBC news report was reflecting on past inflation
rates, and had a graph showing how inflation had increased till it
stayed at 26.9% for a while (in the late 1970s). During this period,
with inflation holding at 26.9%, the reporter commented "prices stood
still".

In article ,
(Paul Corfield) wrote:

Also, is there a time when drivers are required to manually
operate their trains, besides going into depots and sidings?

Yes 67 stock can be manually driven but only at low speeds - can't
remember the maximum but it's very slow compared to auto operation.

The only time drivers will drive in service is if there is a signalling
problem but "coded manual" is possible. This usually results in a crawl
and the driver having the "fan the brakes" as you describe. I haven't
experienced this operation for a long time so I'm not sure if they
would
still use this practice or just simply suspend the service and allow
technicians in to do the fix.

AIUI, it depends on what signalling codes are available from the track.
If they are all there, a 67 stock train can be manually driven up to 25
MPH. Otherwise they are limited to 10 MPH.

--
Colin Rosenstiel

Why did they never build this system with the option to run manual? Did they
not anticiapte that there might be an ATO fault and that drivers would need
to go manual at some point in order to keep traffic moving?

I do find that a bit strange, especially considering that both the Central
and DLR have coded manual operating options.

Also, what does this do to drivers' ability to actually drive a train in
revenue service? In Vienna, for example, drivers are required to manually
operate at the weekend or in the later evening, just to keep them in
practice.

"Colin Rosenstiel" wrote in message
...
In article ,
(Paul Corfield) wrote:

Also, is there a time when drivers are required to manually
operate their trains, besides going into depots and sidings?

Yes 67 stock can be manually driven but only at low speeds - can't
remember the maximum but it's very slow compared to auto operation.

The only time drivers will drive in service is if there is a signalling
problem but "coded manual" is possible. This usually results in a crawl
and the driver having the "fan the brakes" as you describe. I haven't
experienced this operation for a long time so I'm not sure if they
would
still use this practice or just simply suspend the service and allow
technicians in to do the fix.

AIUI, it depends on what signalling codes are available from the track.
If they are all there, a 67 stock train can be manually driven up to 25
MPH. Otherwise they are limited to 10 MPH.

--
Colin Rosenstiel

In article ,
() wrote:

Why did they never build this system with the option to run manual?
Did they not anticiapte that there might be an ATO fault and that
drivers would need to go manual at some point in order to keep
traffic moving?

They did. That's what the 25 MPH capability is for. Don't forget that the
older lines all have 30 MPH as a maximum speed.

I do find that a bit strange, especially considering that both the
Central and DLR have coded manual operating options.

Also, what does this do to drivers' ability to actually drive a
train in revenue service? In Vienna, for example, drivers are
required to manually operate at the weekend or in the later
evening, just to keep them in practice.

--
Colin Rosenstiel

You mean in the tube sections, right? Because I have seen both Piccadilly
and Central lines move at well over those speeds on the surface.


"Colin Rosenstiel" wrote in message
...
In article ,
() wrote:
They did. That's what the 25 MPH capability is for. Don't forget that the
older lines all have 30 MPH as a maximum speed.

I do find that a bit strange, especially considering that both the
Central and DLR have coded manual operating options.

Also, what does this do to drivers' ability to actually drive a
train in revenue service? In Vienna, for example, drivers are
required to manually operate at the weekend or in the later
evening, just to keep them in practice.

--
Colin Rosenstiel

In article ,
() wrote:

"Colin Rosenstiel" wrote in message
...
In article ,
() wrote:
They did. That's what the 25 MPH capability is for. Don't forget
that the older lines all have 30 MPH as a maximum speed.

I do find that a bit strange, especially considering that both the
Central and DLR have coded manual operating options.

Also, what does this do to drivers' ability to actually drive a
train in revenue service? In Vienna, for example, drivers are
required to manually operate at the weekend or in the later
evening, just to keep them in practice.

You mean in the tube sections, right? Because I have seen both
Piccadilly and Central lines move at well over those speeds on the
surface.

Indeed I do. Please don't top-post.

--
Colin Rosenstiel

On 20 Jan, 23:31, (Colin Rosenstiel) wrote:
In article ,
wrote:


You mean in the tube sections, right? Because I have seen both
Piccadilly and Central lines move at well over those speeds on the
surface.

Indeed I do. Please don't top-post.

--
Colin Rosenstiel


Indeed, please don't top-post - bottom-posting is the convention on
usenet, and it makes life easier for all readers if everyone who posts
adheres to it.