Paul Terry wrote:
In message , Paul
Scott writes

It is comparatively difficult for them to overtake one another, and
impossible for them to take a diversionary route in the event of
roadworks,
accidents etc.

Surely it is trams that are unable to divert around roadworks,
accidents, etc. (other than with the aid of crossovers and reverse
working on an adjacent track).

But what normally happens is that dedicated tramways are built. In much
of Croydon this is the case. The trams only run on the roads in the
town centre. Much faster than a bus. At least some parts of Geneva
it's the same too.

--
Paul

"David Bradley" wrote...


OK then let's take on board what you are saying here and let you into
a
preview of a page that will shortly be put up on www.tfwl.org.uk. You
are
invited to make suggested changes to ensure that a middle ground
stance is
taken provided it is honest and accurate.

Well, you've certainly put a lot of work into this. I've got to give
you that, at least.

In my case, the more I get to grips
with the detail of the sheme the more I became concerned about the
sense and
sensability of building a tramway along the Uxbidge Road corridor.
Therefore
everything is slanted towards a trolleybus solution.

I don't believe those are the only two options.

For example, the streetmaps show some branch lines coming off the
Paddington railway line in West London. The Greenford line is still in
use, but the line to Ruislip might as well be closed down, and AIUI the
Hayes (or was it West Drayton?) to Uxbridge line was closed and removed
ages ago. (I'm sure the trainspotters here can give us the full details
if we need them)

Why not convert a couple of those into a tram scheme? Say the Greenford
line (because we know there's a demand for travel in that corridor) and
the old Hayes/Uxbridge line (because TfL apparently wants a transit
going to Uxbridge). Add on-street running to join the two the northern
ends together in a loop and to cover places where the Uxbridge route has
been built over, but the bulk of the lines will remain off-road. This
way, it'll be building on TfL's solid, practical experience of running a
mostly off-road tram network in Croydon. The links to Crossrail at the
southern ends will be more useful to central London commuters than TfL's
pointless proposal for a Shepherd's Bush terminus. And the fact that
it's mostly a new rapid-transit route will grab people's attention more
than just adding overhead wires to existing bus routes. (And while
we're at it, what about sending some Crossrail trains up the old line to
Ruislip?)

No. I'm not seriously proposing this scheme. Just showing that a
couple of minutes thinking outside the box can produce other new ideas
at least as viable as TfL's trams vs. your trolleybuses. Just because
there are flaws in TfL's scheme, it doesn't automatically make
trolleybuses the best of all possible options.

Solving congestion may be a rather tall order. If anyone claims that
any form
of WLT scheme (tram, trolleybus or whatever) is going to 'solve
congestion
across West London', they are to quote (a polite version of) the
phrase:
'talking through their hat'.

I don't think anyone's trying 'to solve congestion across all of West
London.' Just reducing it along one main road is a much more realistic
target.

What is needed is a whole
package of measures which will improve both the actuality and
perception of
public transport in this area and thus reduce the use of cars as much
as
possible.

We need to 'improve both the actuality and perception of public
transport' in all areas. There's nothing special about West London.

WLT as a tram scheme does not give any greater benefits along the
Uxbridge Road than a trolleybus scheme would but costs very much more.

Warning. Now you're starting to use vague weasel-words. *A* tram
scheme may or may not be better than *a* trolleybus scheme. It depends
on the details of the schemes.

Also the very nature of the WLT tram scheme
proposed is likely to worsen flows by buses which are not simply along
the
Uxbridge Road (by creating a greater requirement to change - which is
universally unpopular and thus often causes modal shift the wrong
way).

The advantages of trolleybuses is that they are non-polluting on
street.

Ah, now, do you see what you did there? You were talking about an
advantage of trolleybuses over TfL's tram scheme, then in the next
paragraph you continued talking about "advantages of trolleybuses" but
actually, you've changed to their advantage over diesel buses. It gives
the misleading impression that trams ARE polluting on street.

The ability to steer trolleybuses across (both) the carriageway(s) and
the
design of the vehicles means that they can be better integrated into
the
overall bus provision along the corridor.

Better integrated than diesel buses? Really? Oh, wait, no. You've
sneakily switched reference points without telling us again and now
you're comparing trolley buses to trams once more. Naughty David. You
should be ashamed of yourself.

There is no need to curtail services
as will be done in the proposed tram solution.

Sadly, long routes will probaly be split and curtailed anyway. It
always happens. The tram would just've been a convenient excuse, but
they'll find some other reason to curtail them if they look hard enough.

This will therefore be
beneficial in the general area around the Uxbridge Road. The lesser
capital
costs will allow funding to be available to improve these services
further
(including possibly electrifying many of them into trolleybus routes).

You're rather niave if you think that TfL will automatically ringfence
the saved money purely for the general area around the Uxbridge Road.
They'll probably either spend it across all of London, or just line
their pockets with it. I wouldn't dare say which one it'll be.

As the design of WLT as a tramway does not integrate bus stops with
trams stops

I would hope that whatever mode of WLT is chosen, it wouldn't integrate
its stops with bus stops. Keeping them separate would help establish it
in the public's imagination as something new and different. This will
help stimulate their curiosity more than just the same old bus routes
calling at the same old bus stops but with added overhead cables.


and even a 25 metre double artic would describe the same swept path.
There is
no experience whatsoever of 40 metre trams in UK streets, so we have
no
knowledge of how they will fare even with their fixed path.

How much experience of 25 metre double artic trolleybuses is there in UK
streets? If experience matters for one, it should matter for both.

Even in that rarest of all situations that the overhead were damaged,
trolleybuses could still operate using auxiliary power

Is there any technical reason why trams can't be designed with auxiliary
power for emergencies? I know TfL's specific tram scheme doesn't, but
you do seem to be making the falacy of assuming that just because one
particular trolleybus scheme is better than one possible tram scheme,
therefore it must also be better than all possible tram schemes and all
other possible schemes as well.

The MORI survey (the one where the one line 'support for the scheme'
headline
is usually quoted) does not indicate that 'everyone' is in favour of
the
scheme - very far from it.

Well, it would be VERY suspicious if a survey said 100% of people
supported anything.

Conversely many of those who 'supported' the scheme
stated themselves that they had only limited knowledge of it. As more
of the
precise details are released, it is likely that even more people will
oppose
the scheme and not because they are all NIMBY drivers of gas guzzling
4 X 4
cars as is often disingenuously argued by pro-tram supporters but
because they
can see that the tram is not the optimum mode for this particular
corridor

Yes, but you're making that falacy again. You're assuming that just
beacuse TfL's tram is not the optimum mode and your trolleybus isn't
TfL's tram, therefore your trolleybus must be the optimum mode. It
doesn't work like that. The world isn't all black and white. There are
middle grounds and other options, but you aren't even interested in
exploring them because of your trolleybus fixation.


It's make you mind up time.


Make our minds up? We haven't even begun to discover all the options
yet...

In message ,
writes
Just showing that a couple of minutes thinking outside the box
Which means?
--
Clive

In article , David Bradley
writes
In fact in Rome where
a new trolleybus systen has been introduced, part of the route has no overhead
wiring because of a desire to have a clutter free skyline in an area of
particular historical importance. The booms can be disconnected and
reconnected to the wires without the need for the driver [or crew] to leave
the vehicle. Clearly this ability can also be used in the first point that
you made. I don't see too much difficulty in flicking a switch to lower or
raise the booms as required, thus enabling that fabled overtaking of service
vehicles,

The only places where I've seen this de-wiring and re-wiring
arrangement, the re-wiring can only be done at specific locations -
there's a sort of plastic M attached to the wires that guides the booms
into place. This is fine for the sort of situation you describe in Rome,
but it does *not* work for unplanned overtaking.

--
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:

In article , David Bradley
writes
High speeds are not likely to be a problem along the Uxbridge Road (the
proposed mean speed for the tramway is 13 M.P.H.!).

Is this mean speed while running, mean speed calculated start-to-stop,
or mean speed from end point to end point? There's a huge difference
between these.

For example, consider a route 10km long with 29 intermediate stops (that
is, a stop every 333m), assume that the dwell time at stops is 30
seconds, and that trams can accelerate and brake at 2m/s^2. I'll use
5m/s (11.2mph) for ease of calculation:

* End-to-end speed of 5m/s means end-to-end time of 2000 seconds (just
under 35 minutes).
* 870 seconds is spent stopped, so that's 1130 seconds of running time,
or just under 38 seconds between stops. That's a start-to-stop speed of
8.85m/s (19.9mph).
* This requires accelerating to 10m/s (22.5mph), running at that speed
for 28 seconds, then decelerating again.

So the end-to-end speed is only half the service speed.

There is
no experience whatsoever of 40 metre trams in UK streets, so we have no
knowledge of how they will fare even with their fixed path.

There is experience with coupled pairs in Manchester and even Blackpool.
We also have hundreds of years of experience of rail transport which
shows us that all the vehicles follow the same fixed path, whether the
combination is 5 or 500m long.

--
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:

In article ,
(Clive D. W. Feather) wrote:

In article , David
Bradley
In fact in Rome where
a new trolleybus systen has been introduced, part of the route has
no overhead wiring because of a desire to have a clutter free skyline
in an area of particular historical importance. The booms can be
disconnected and reconnected to the wires without the need for the
driver [or crew] to leave the vehicle. Clearly this ability can also
be used in the first point that you made. I don't see too much
difficulty in flicking a switch to lower or raise the booms as
required, thus enabling that fabled overtaking of service vehicles,

The only places where I've seen this de-wiring and re-wiring
arrangement, the re-wiring can only be done at specific locations -
there's a sort of plastic M attached to the wires that guides the
booms into place. This is fine for the sort of situation you describe
in Rome, but it does *not* work for unplanned overtaking.

I remember a careless trolleybus driver trying to overtake another
trolleybus on Putney Bridge. It didn't take that long to replace the
booms on the wires with just the bamboo trolley retrieval poles of those
days.

--
Colin Rosenstiel

On Thu, 10 Nov 2005 10:02:33 +0000, "Clive D. W. Feather"
wrote:

In article , David Bradley
writes
High speeds are not likely to be a problem along the Uxbridge Road (the
proposed mean speed for the tramway is 13 M.P.H.!).

Is this mean speed while running, mean speed calculated start-to-stop,
or mean speed from end point to end point? There's a huge difference
between these.

For example, consider a route 10km long with 29 intermediate stops (that
is, a stop every 333m), assume that the dwell time at stops is 30
seconds, and that trams can accelerate and brake at 2m/s^2. I'll use
5m/s (11.2mph) for ease of calculation:

* End-to-end speed of 5m/s means end-to-end time of 2000 seconds (just
under 35 minutes).
* 870 seconds is spent stopped, so that's 1130 seconds of running time,
or just under 38 seconds between stops. That's a start-to-stop speed of
8.85m/s (19.9mph).
* This requires accelerating to 10m/s (22.5mph), running at that speed
for 28 seconds, then decelerating again.

So the end-to-end speed is only half the service speed.

There is
no experience whatsoever of 40 metre trams in UK streets, so we have no
knowledge of how they will fare even with their fixed path.

There is experience with coupled pairs in Manchester and even Blackpool.
We also have hundreds of years of experience of rail transport which
shows us that all the vehicles follow the same fixed path, whether the
combination is 5 or 500m long.

It is unfortunate that all this nit picking continues with statements that I
make concerning the viablity of tramway services along the Uxbridge Road.
Responses to inaccurate statements, such as made here, have to be challeged
before they become folklore. I would really prefere to actively persue
development of my web site www.tfwl.org.uk where true facts are given
following the most detailed research, as far as time permits, in anything that
is said there.

So you don't like the statement that mean speed for the tramway is quoted as
13 MPH. Well various TfL reports give the overall jourrney time from Uxbridge
to Shepherd's Bush (20 km.) of around an hour and the mean end to end speed
(thus including stops) of 19 or 20 k.p.h. (depends on which report!). I have
(slightly generously) approximated this to 13 m.p.h.

Clearly the vehicles should be able to exceed this between stops but it is
unlikely that they will exceed 30 m.p.h. ( 48 k.p.h.) in doing so and in many
places they will going far slower. They will have no opportunity for 'high
speed' running of 50 m.p.h. (80 k.p.h.) which Croydon Tramlink achieves on
many sections.

Manchester is essentially railway branches joined together with very limited
street running in between and a small section at the end of the Eccles Line.
Blackpool is not on-street either except for a part at the Fleetwood end. The
point is that the Uxbridge Road is **ALL** street and of course as all the
information reminds us, a very congested street at that.

The issue is not that of the path of the tram. That is clearly defined by the
rails, as stated, The question is how you can fit the 40 metre length in the
street between junctions, tram stops, stationary traffic of one sort or
another, traffic 'nipping in' etc. Even with the flexibility of path available
(by steering) of a bus, 'bendies' on London routes often have to be guided
very carefully to be able to be squeezed into the available road space and
these are 18 metres long. The tram has to occupy 40 metres of carriageway at
any time. I believe that to get a clear 40 metres along some of the more
heavily congested sections of this road, may at many times prove difficult and
the tram will be delayed not because other traffic has stopped, but because of
its own size. A good analogy would be that of artic lorries which are often
unable to proceed even when other traffic is moving because there simply is
not enough carriageway into which they can fit. the tram will of course be
over twice the length of any artic lorry.

This sort of problem can be experienced daily (only to a lesser extent as the
trams are shorter than 40 metres) in those cities with extensive street
running of their trams and congested streets such as Turin for example.

David Bradley

On Fri, 11 Nov 2005 07:42:41 +0000, David Bradley
wrote:

On Thu, 10 Nov 2005 10:02:33 +0000, "Clive D. W. Feather"
wrote:

In article , David Bradley
writes

There is
no experience whatsoever of 40 metre trams in UK streets, so we have no
knowledge of how they will fare even with their fixed path.

There is experience with coupled pairs in Manchester and even Blackpool.
We also have hundreds of years of experience of rail transport which
shows us that all the vehicles follow the same fixed path, whether the
combination is 5 or 500m long.

The issue is not that of the path of the tram. That is clearly defined by the
rails, as stated, The question is how you can fit the 40 metre length in the
street between junctions, tram stops, stationary traffic of one sort or
another, traffic 'nipping in' etc. Even with the flexibility of path available
(by steering) of a bus, 'bendies' on London routes often have to be guided
very carefully to be able to be squeezed into the available road space and
these are 18 metres long. The tram has to occupy 40 metres of carriageway at
any time. I believe that to get a clear 40 metres along some of the more
heavily congested sections of this road, may at many times prove difficult and
the tram will be delayed not because other traffic has stopped, but because of
its own size. A good analogy would be that of artic lorries which are often
unable to proceed even when other traffic is moving because there simply is
not enough carriageway into which they can fit. the tram will of course be
over twice the length of any artic lorry.

This sort of problem can be experienced daily (only to a lesser extent as the
trams are shorter than 40 metres) in those cities with extensive street
running of their trams and congested streets such as Turin for example.

The U9 (I think) that runs between Duesseldorf and Duisburg has a
considerable stretch of street running after it emerges from below
ground and before it goes onto reserved track north of the Messe.

When they run double units, it takes up almost all the road between
certain pairs of traffic signals. If that coincides with a tram stop,
it stops everything.
--
Terry Harper
Website Coordinator, The Omnibus Society
http://www.omnibussoc.org

David, did you see my post? I'm repeating it here for you, just in case
you missed it.



wrote...

"David Bradley" wrote...


OK then let's take on board what you are saying here and let you
into a preview of a page that will shortly be put up on
www.tfwl.org.uk. You are invited to make suggested changes to ensure
that a middle ground stance is taken provided it is honest and
accurate.

Well, you've certainly put a lot of work into this. I've got to give
you that, at least.

In my case, the more I get to grips
with the detail of the sheme the more I became concerned about the
sense and sensability of building a tramway along the Uxbidge Road
corridor. Therefore everything is slanted towards a trolleybus
solution.

I don't believe those are the only two options.

For example, the streetmaps show some branch lines coming off the
Paddington railway line in West London. The Greenford line is still
in use, but the line to Ruislip might as well be closed down, and
AIUI the Hayes (or was it West Drayton?) to Uxbridge line was closed
and removed ages ago. (I'm sure the trainspotters here can give us
the full details if we need them)

Why not convert a couple of those into a tram scheme? Say the
Greenford line (because we know there's a demand for travel in that
corridor) and the old Hayes/Uxbridge line (because TfL apparently
wants a transit going to Uxbridge). Add on-street running to join
the two the northern ends together in a loop and to cover places
where the Uxbridge route has been built over, but the bulk of the
lines will remain off-road. This way, it'll be building on TfL's
solid, practical experience of running a mostly off-road tram network
in Croydon. The links to Crossrail at the southern ends will be more
useful to central London commuters than TfL's pointless proposal for
a Shepherd's Bush terminus. And the fact that it's mostly a new
rapid-transit route will grab people's attention more than just
adding overhead wires to existing bus routes. (And while we're at
it, what about sending some Crossrail trains up the old line to
Ruislip?)

No. I'm not seriously proposing this scheme. Just showing that a
couple of minutes thinking outside the box can produce other new ideas
at least as viable as TfL's trams vs. your trolleybuses. Just because
there are flaws in TfL's scheme, it doesn't automatically make
trolleybuses the best of all possible options.

Solving congestion may be a rather tall order. If anyone claims that
any form of WLT scheme (tram, trolleybus or whatever) is going to
'solve congestion across West London', they are to quote (a polite
version of) the phrase: 'talking through their hat'.

I don't think anyone's trying 'to solve congestion across all of West
London.' Just reducing it along one main road is a much more
realistic target.

What is needed is a whole
package of measures which will improve both the actuality and
perception of public transport in this area and thus reduce the use
of cars as much as possible.

We need to 'improve both the actuality and perception of public
transport' in all areas. There's nothing special about West London.

WLT as a tram scheme does not give any greater benefits along the
Uxbridge Road than a trolleybus scheme would but costs very much
more.

Warning. Now you're starting to use vague weasel-words. *A* tram
scheme may or may not be better than *a* trolleybus scheme. It
depends on the details of the schemes.

Also the very nature of the WLT tram scheme
proposed is likely to worsen flows by buses which are not simply
along the Uxbridge Road (by creating a greater requirement to change
- which is universally unpopular and thus often causes modal shift
the wrong way).

The advantages of trolleybuses is that they are non-polluting on
street.

Ah, now, do you see what you did there? You were talking about an
advantage of trolleybuses over TfL's tram scheme, then in the next
paragraph you continued talking about "advantages of trolleybuses" but
actually, you've changed to their advantage over diesel buses. It
gives the misleading impression that trams ARE polluting on street.

The ability to steer trolleybuses across (both) the carriageway(s)
and the design of the vehicles means that they can be better
integrated into the overall bus provision along the corridor.

Better integrated than diesel buses? Really? Oh, wait, no. You've
sneakily switched reference points without telling us again and now
you're comparing trolley buses to trams once more. Naughty David.
You should be ashamed of yourself.

There is no need to curtail services
as will be done in the proposed tram solution.

Sadly, long routes will probaly be split and curtailed anyway. It
always happens. The tram would just've been a convenient excuse, but
they'll find some other reason to curtail them if they look hard
enough.

This will therefore be
beneficial in the general area around the Uxbridge Road. The lesser
capital costs will allow funding to be available to improve these
services further (including possibly electrifying many of them into
trolleybus routes).

You're rather niave if you think that TfL will automatically ringfence
the saved money purely for the general area around the Uxbridge Road.
They'll probably either spend it across all of London, or just line
their pockets with it. I wouldn't dare say which one it'll be.

As the design of WLT as a tramway does not integrate bus stops with
trams stops

I would hope that whatever mode of WLT is chosen, it wouldn't
integrate its stops with bus stops. Keeping them separate would help
establish it in the public's imagination as something new and
different. This will help stimulate their curiosity more than just
the same old bus routes calling at the same old bus stops but with
added overhead cables.


and even a 25 metre double artic would describe the same swept path.
There is no experience whatsoever of 40 metre trams in UK streets,
so we have no knowledge of how they will fare even with their fixed
path.

How much experience of 25 metre double artic trolleybuses is there in
UK streets? If experience matters for one, it should matter for both.

Even in that rarest of all situations that the overhead were damaged,
trolleybuses could still operate using auxiliary power

Is there any technical reason why trams can't be designed with
auxiliary power for emergencies? I know TfL's specific tram scheme
doesn't, but you do seem to be making the falacy of assuming that
just because one particular trolleybus scheme is better than one
possible tram scheme, therefore it must also be better than all
possible tram schemes and all other possible schemes as well.

The MORI survey (the one where the one line 'support for the scheme'
headline is usually quoted) does not indicate that 'everyone' is in
favour of the scheme - very far from it.

Well, it would be VERY suspicious if a survey said 100% of people
supported anything.

Conversely many of those who 'supported' the scheme
stated themselves that they had only limited knowledge of it. As
more of the precise details are released, it is likely that even
more people will oppose the scheme and not because they are all
NIMBY drivers of gas guzzling 4 X 4 cars as is often disingenuously
argued by pro-tram supporters but because they can see that the tram
is not the optimum mode for this particular corridor

Yes, but you're making that falacy again. You're assuming that just
beacuse TfL's tram is not the optimum mode and your trolleybus isn't
TfL's tram, therefore your trolleybus must be the optimum mode. It
doesn't work like that. The world isn't all black and white. There
are middle grounds and other options, but you aren't even interested
in exploring them because of your trolleybus fixation.


It's make you mind up time.


Make our minds up? We haven't even begun to discover all the options
yet...

--

David Bradley wrote:

On 7 Nov 2005 07:23:36 -0800, wrote:

David Bradley wrote:

On Mon, 7 Nov 2005 11:12:17 -0000, wrote:

Now maybe you just happen to like bendy-buses with overhead power lines
for their own sake? But experience seems to show that simply sticking
bendy buses onto already overcrowded roads doesn't reduce congestion. I
don't see how they're going to fix that problem by just adding some ugly
power lines to the bus.

40 metre long trains, TWICE the length of bendybuses, running along Uxbridge
Road is really going to make a difference for the better or worse? Your call
to explain that one away.

Perhaps it is, but it doesn't alter the fact that you haven't answered
the question.

Well let's have a go then although I have never said anything about using
bendy trolleybuses although it's fair to assume that is what will be used.

Not much of a go, unfortunately - the question was about why a
trolleybus would reduce traffic congestion more than a similarly-sized
diesel bus. The question isn't about pollution, or environmental
issues, or the appearance of overhead wiring. They are all subjects
worthy of debate in their own right, but they aren't the question
currently posed.

So how about taking another shot at it?


Now it's about time you made your position clear of which mode of transport
you prefer and why.

I'm undecided, and open-minded, and open to persuasion by sensible
debate.