d wrote on 05 December 2013 09:27:42 ...
On Wed, 04 Dec 2013 22:34:30 +0000
"Richard J." wrote:
There was an interesting report in Le Parisien newspaper last month that
said that dwell times had reduced on line 1 since it became driverless,
as passengers had become more disciplined because they knew there wasn't
a driver to hold the doors open for a bit longer if they were slow in
boarding.

Some drivers on LU seem to be rather slow to close the doors even when
there's no one left on the platform. They waste a good 5 - 10 seconds at
each stop which probably buggers up the timetable nicely by the time they've
got to the other end of the line.

If it's the Piccadilly line, that sort of thing will ensure they don't
run early against the leisurely timetable. I guess they think it's
better to waste a few seconds here and there instead of being held at a
station further down the line for a couple of minutes "to regulate the
service".
--
Richard J.
(to email me, swap 'uk' and 'yon' in address)

On Thu, 05 Dec 2013 21:19:10 +0000
"Richard J." wrote:
wrote on 05 December 2013 09:27:42 ...
Some drivers on LU seem to be rather slow to close the doors even when
there's no one left on the platform. They waste a good 5 - 10 seconds at
each stop which probably buggers up the timetable nicely by the time they've
got to the other end of the line.

If it's the Piccadilly line, that sort of thing will ensure they don't
run early against the leisurely timetable. I guess they think it's
better to waste a few seconds here and there instead of being held at a
station further down the line for a couple of minutes "to regulate the
service".

They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway? They just run up and down the line and stop at the
end of the day. The drivers obviously need a roster but what difference does
it make if they pick up train A, B, C or D? They're all the bloody same.

--
Spud

In message , at 16:16:07 on Fri, 6 Dec
2013, d remarked:
Some drivers on LU seem to be rather slow to close the doors even when
there's no one left on the platform. They waste a good 5 - 10 seconds at
each stop which probably buggers up the timetable nicely by the time they've
got to the other end of the line.

If it's the Piccadilly line, that sort of thing will ensure they don't
run early against the leisurely timetable. I guess they think it's
better to waste a few seconds here and there instead of being held at a
station further down the line for a couple of minutes "to regulate the
service".

They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway?

They are trying to avoid the "three buses come at once" scenario. It's
in the nature of public transport that the first to arrive picks up most
of the passengers, which slows it down. The one behind has fewer
passengers to pick up and gradually gains on the one in front.
Eventually they end up running in convoy.
--
Roland Perry

On Fri, 6 Dec 2013 16:21:30 +0000
Roland Perry wrote:
In message , at 16:16:07 on Fri, 6 Dec
They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway?

They are trying to avoid the "three buses come at once" scenario. It's
in the nature of public transport that the first to arrive picks up most
of the passengers, which slows it down. The one behind has fewer
passengers to pick up and gradually gains on the one in front.
Eventually they end up running in convoy.

Thats true, but unlike buses which can come up right behind and pass each
other , with trains the signalling will keep them a certain distance apart
anyway. And since there's no other traffic unlike on the roads there's no
reason for any one train to have many more passengers than another if they
come at frequent regular intervals. The amount of people waiting at 8am is
going to be pretty much the same as at 8.05 since any people the train picks
up will be replace by those entering the station.

--
Spud

In message , at 16:46:45 on Fri, 6 Dec
2013, d remarked:
They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway?

They are trying to avoid the "three buses come at once" scenario. It's
in the nature of public transport that the first to arrive picks up most
of the passengers, which slows it down. The one behind has fewer
passengers to pick up and gradually gains on the one in front.
Eventually they end up running in convoy.

Thats true, but unlike buses which can come up right behind and pass each
other , with trains the signalling will keep them a certain distance apart
anyway. And since there's no other traffic unlike on the roads there's no
reason for any one train to have many more passengers than another if they
come at frequent regular intervals. The amount of people waiting at 8am is
going to be pretty much the same as at 8.05 since any people the train picks
up will be replace by those entering the station.

The trains are further apart than the line capacity, and the situation
is inherently unstable, resulting in the "regulate" waits.
--
Roland Perry

On Fri, 6 Dec 2013 16:54:26 +0000, Roland Perry
wrote:

In message , at 16:46:45 on Fri, 6 Dec
2013, d remarked:
They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway?

They are trying to avoid the "three buses come at once" scenario. It's
in the nature of public transport that the first to arrive picks up most
of the passengers, which slows it down. The one behind has fewer
passengers to pick up and gradually gains on the one in front.
Eventually they end up running in convoy.

Thats true, but unlike buses which can come up right behind and pass each
other , with trains the signalling will keep them a certain distance apart
anyway. And since there's no other traffic unlike on the roads there's no
reason for any one train to have many more passengers than another if they
come at frequent regular intervals. The amount of people waiting at 8am is
going to be pretty much the same as at 8.05 since any people the train picks
up will be replace by those entering the station.

The trains are further apart than the line capacity, and the situation
is inherently unstable, resulting in the "regulate" waits.

Few of the Underground lines run a self-contained service thus
departing from the timetable will in most cases also mess up another
line's (or the same line in the other direction for the self-contained
lines) service if trains are allowed to run in a random manner. Even
where there isn't actual track sharing, bunching of trains will also
lead to a similar effect with passengers at various interchanges;
where there is track sharing (e.g. District + NLL, Bakerloo + DC
line), random running of LU services has IME been a long term cause of
screwing up the published timetables for the NR services.

On 06/12/2013 16:16, d wrote:
On Thu, 05 Dec 2013 21:19:10 +0000
"Richard J." wrote:
d wrote on 05 December 2013 09:27:42 ...
Some drivers on LU seem to be rather slow to close the doors even when
there's no one left on the platform. They waste a good 5 - 10 seconds at
each stop which probably buggers up the timetable nicely by the time they've
got to the other end of the line.

If it's the Piccadilly line, that sort of thing will ensure they don't
run early against the leisurely timetable. I guess they think it's
better to waste a few seconds here and there instead of being held at a
station further down the line for a couple of minutes "to regulate the
service".

They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway? They just run up and down the line and stop at the
end of the day. The drivers obviously need a roster but what difference does
it make if they pick up train A, B, C or D? They're all the bloody same.


The diagrams are different, not all trains go right to the end of the
line, then you have all the different branches. Many metro systems are
just a collection of there and back lines which will be much simpler to
operate.


--
Graeme Wall
This account not read, substitute trains for rail.
Railway Miscellany at http://www.greywall.demon.co.uk/rail

On Fri, 06 Dec 2013 16:50:28 +0000
Graeme Wall wrote:
On 06/12/2013 16:16, d wrote:
They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway? They just run up and down the line and stop at the
end of the day. The drivers obviously need a roster but what difference does
it make if they pick up train A, B, C or D? They're all the bloody same.


The diagrams are different, not all trains go right to the end of the
line, then you have all the different branches. Many metro systems are
just a collection of there and back lines which will be much simpler to
operate.

Well there is that. But the jubilee, bakerloo, victoria & W&C are just there
and back lines so why do they need a timetable? Even on more complicated
lines you could have some sort of train recognition system whereby the driver
types in his route at the start of his trip and the signalling sets the
route according to the trains id when it gets to certain junctions. No need
for a timetable.

--
Spud

wrote:
On Fri, 06 Dec 2013 16:50:28 +0000
Graeme Wall wrote:
On 06/12/2013 16:16, d wrote:
They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway? They just run up and down the line and stop at the
end of the day. The drivers obviously need a roster but what difference does
it make if they pick up train A, B, C or D? They're all the bloody same.


The diagrams are different, not all trains go right to the end of the
line, then you have all the different branches. Many metro systems are
just a collection of there and back lines which will be much simpler to
operate.

Well there is that. But the jubilee, bakerloo, victoria & W&C are just there
and back lines so why do they need a timetable? Even on more complicated
lines you could have some sort of train recognition system whereby the driver
types in his route at the start of his trip and the signalling sets the
route according to the trains id when it gets to certain junctions. No need
for a timetable.

Many of these trains don't travel the full length of the line (apart from
the Drain, of course), and Bakerloo trains have to mix with scheduled
Overground services. But the reason to regulate the services is not just to
maintain the timetable, but to stop trains bunching after one has been held
up for any reason.

On 07/12/2013 10:46, d wrote:
On Fri, 06 Dec 2013 16:50:28 +0000
Graeme Wall wrote:
On 06/12/2013 16:16, d wrote:
They do that anyway even if there hasn't been a train througn for 10 minutes.
I don't think I've ever been on another metro system that has to "regulate"
itself. The trains just run. If you have trains every 2 minutes why do you
need a timetable anyway? They just run up and down the line and stop at the
end of the day. The drivers obviously need a roster but what difference does
it make if they pick up train A, B, C or D? They're all the bloody same.


The diagrams are different, not all trains go right to the end of the
line, then you have all the different branches. Many metro systems are
just a collection of there and back lines which will be much simpler to
operate.

Well there is that. But the jubilee, bakerloo, victoria & W&C are just there
and back lines

They aren't completely. Not all trains go all the way every trip and the
H&C has to dovetail into the Met, District and Circle lines.

so why do they need a timetable? Even on more complicated
lines you could have some sort of train recognition system whereby the driver
types in his route at the start of his trip and the signalling sets the
route according to the trains id when it gets to certain junctions. No need
for a timetable.


Reinventing the wheel. I suggest you read up on TfL's regulatory system.


--
Graeme Wall
This account not read, substitute trains for rail.
Railway Miscellany at http://www.greywall.demon.co.uk/rail