So on 'environmental grounds' they want the more capable and
efficient over head system replaced by an inadequate and possibly
dangerous ground level system.

I've seen a number of 'environmental' objections over the years
(don't mess up my view) that when implemented have resulted in a less
efficient system. (Particularly route changes that result in tougher
grades, hence greater energy use).

Some one should go through such objections and attach a long term
running cost to them, both in maintenance and 'carbon cost' of on
going energy use implications.

Peter Masson wrote:
Airtrack, as currently planned, will terminate at T5. It has been stated
that the tunnel approach to the station, and the Airtrack platforms at T5
will have to be 25kV OHLE, though I haven't seen an explanation of why this
is so.

I wondered about corrosion of rails etc in the tunnels?

This being the case, there will have to be a voltage change somewhere
between Staines and T5. It would seem to make sense, in the longer term, for
Airtrack and Heathrow Express and/or Crossrail to link up, with through
running, which of course would require dual-voltage stock and a voltage
change somewhere. An intermediate possibility is for HEx to be extended to
Staines.

So that starts to make the case for a change at Staines...

Theo

On Sun, 20 Apr 2008 11:35:44 +0100, "Paul Scott"
wrote:

furnessvale wrote:
On Apr 20, 7:24?am, Mwmbwls wrote:
Spelthorne Councillors seek to choose Airtrack electrification
voltage. It reminds me of the days when London had conduit trams
because overhead wires were considered unsightly - but then at least
they owned the streets and the trams - unlike Spelthorne. This is
surely a technical rather than a political question. Note also Mr
Livingstone's response.

It is a bit rich that they object on pseudo-environmental reasons when
the whole area already stinks of unburnt fuel.


I don't know the details of the scheme but if it is new build I doubt
thrird rail would be allowed. If it is allowed as an "infill" I hope
the councillors take on the job of delivering the death messages to
parents when the kiddywinkies get zapped.


It definitely ought to be allowed as infill of the third rail network - it
is only about 2 miles from the point the route leaves the Windsor line to
the buffer stops under T5, and they aren't going to add overheads all the
way to Reading, Guildford and Waterloo...

The recent report (we discussed it a few weeks ago) just reckons there are
'technical difficulties' in running on third rail all the way into T5 - so
what are these?

The need for more substations ? No doubt Spelthorne council would find
a reason to object to them.

The basic airtrack scheme has trains running into
terminating platforms which are separate from the existing HEx platforms.

Clearly there will be other voltage changeover issues if HEx is run all the
way to Staines as well (which IIRC is the only scenario that has OHLE into
Staines.

I think Livingstone is doing the status of the project down a bit - if
Spelthorne council are already dealing with consultation issues at commitee
level. The fact he hasn't had a personal presentation on the subject doesn't
mean the consultation (documents easily found on the www) isn't happening...

On Sun, 20 Apr 2008, Richard J. wrote:

Mwmbwls wrote:

Preliminary Airtrack plans - designed to provide new rail access to
Heathrow from the south and west - were discussed at the meeting of
Spelthorne Council's executive committee on Tuesday. It voted to
strongly oppose overhead electrification on environmental grounds.

That's rich, coming from the council that did a U-turn and voted in
favour of Heathrow expansion. They don't mind destroying someone else's
village and forcing environmental damage on thousands of West London
residents, but they don't want the view of their sodding bit of grass
spoilt.

Aha - 'sodding grass'. Very good.

tom

--
Initial thoughts - who cares? Subsequent thoughts - omg!!! (Female, 14,
Scotland) -- 4.5 million young Brits' futures could be compromised by
their electronic footprint, Information Commissioner's Office

On Sun, 20 Apr 2008, Peter Masson wrote:

"Theo Markettos" wrote

Airtrack's going to have to have a voltage changeover point somewhere.
The council have suggested it should be at T5 for environmental
reasons. I don't see a problem with them saying that, if it is just a
proposal. There may well be technical, operational or other reasons
which means third rail is impractical or costly on that stretch but
that's for the developers to make a case for.

Airtrack, as currently planned, will terminate at T5.

Yes. Which means there's no reason for any OHLE at all.

It has been stated that the tunnel approach to the station, and the
Airtrack platforms at T5 will have to be 25kV OHLE, though I haven't
seen an explanation of why this is so.

Which would be nice to see, because that sounds like a totally bonkers
idea.

This being the case, there will have to be a voltage change somewhere
between Staines and T5. It would seem to make sense, in the longer term,
for Airtrack and Heathrow Express and/or Crossrail to link up, with
through running, which of course would require dual-voltage stock and a
voltage change somewhere.

In which case, since the stock will have to be dual-voltage anyway, why
bother making the Airtrack bit OHLE? Why not have the change at T5, thus
allowing third-rail trains to run from the south into T5 too?

An intermediate possibility is for HEx to be extended to Staines.

This is the only reason i can think of for doing it. Even then, it means
sacrificing the ability to run third-rail stock into T5 for this mythical
future option. Is it the case that existing stock won't be allowed anyway,
for safety or ABB [1] reasons?

tom

[1] Arbitrary BAA bull****

--
Initial thoughts - who cares? Subsequent thoughts - omg!!! (Female, 14,
Scotland) -- 4.5 million young Brits' futures could be compromised by
their electronic footprint, Information Commissioner's Office

"Matthew Geier" wrote in message
...

So on 'environmental grounds' they want the more capable and
efficient over head system replaced by an inadequate and possibly
dangerous ground level system.


I think you are missing the factt that it really is only a very short
extension to an existing third rail system if they ran third rail into the
T5 basement - and there can't really be much of a 'technical issue' given
the neighbouring LU tracks for the Piccadilly. Staying with third rail
would mean the TOC (SWT or successor) wouldn't need a sub class of dual
voltage rolling stock, so there would be advantages in terms of train
diagramming.

Paul S

"Tom Anderson" wrote in message
h.li...

An intermediate possibility is for HEx to be extended to Staines.

This is the only reason i can think of for doing it. Even then, it means
sacrificing the ability to run third-rail stock into T5 for this mythical
future option.

As the consultation report points out though, the two dedicated Airtrack
platforms under T5 are a terminus from the west, it is only the HEx
platforms that can be turned into through platforms, joining Airtrack
somewhere to the west of the station. So even extensions to HEx might'nt
necessarily affect terminating DC trains if the changeover was in the
vicinity of the station.

Is it the case that existing stock won't be allowed anyway, for safety or
ABB [1] reasons?

If existing stock such as 450s was used by SWT - except for having shoes
rather than pantograph it is to all intents identical to the Heathrow
Connect 360s [ref other discussions about AC traction in all modern EMUs],
with the end gangways being an additional safety feature, [although not
required in the Heathrow tunnels as they have walkways].

I also don't believe there are any increased safety issues with underground
third rail stations, if there was such a huge issue why would they be
carrying on with a new third rail installation for the ELL? Another poster
has mentioned corrosion in the tunnels, but this is surely overcome with
modern slab track and fastenings in concrete linings - they don't suffer
from groundwater ingress like the early LU tunnels...

Paul S

Paul Scott wrote:
"Matthew Geier" wrote in message
...
So on 'environmental grounds' they want the more capable and
efficient over head system replaced by an inadequate and possibly
dangerous ground level system.


I think you are missing the factt that it really is only a very short
extension to an existing third rail system if they ran third rail into the
T5 basement - and there can't really be much of a 'technical issue' given
the neighbouring LU tracks for the Piccadilly. Staying with third rail
would mean the TOC (SWT or successor) wouldn't need a sub class of dual
voltage rolling stock, so there would be advantages in terms of train
diagramming.

I thought the intention was to 'extend' Hex to Staines, to enable
interchange with Reading/Windsor lines. You can only do that if you 25kv
that short bit. Doesn't the adjacent M25 have 'catenary' lighting.
Perhaps they should take away all lighting on that bit to reduce
environmental damage- or why just stop at removing lighting...

Jim Chisholm

J. Chisholm wrote:
Paul Scott wrote:
"Matthew Geier" wrote in message
...
So on 'environmental grounds' they want the more capable and
efficient over head system replaced by an inadequate and possibly
dangerous ground level system.


I think you are missing the factt that it really is only a very short
extension to an existing third rail system if they ran third rail
into the T5 basement - and there can't really be much of a
'technical issue' given the neighbouring LU tracks for the
Piccadilly. Staying with third rail would mean the TOC (SWT or
successor) wouldn't need a sub class of dual voltage rolling stock,
so there would be advantages in terms of train diagramming.

I thought the intention was to 'extend' Hex to Staines, to enable
interchange with Reading/Windsor lines. You can only do that if you
25kv that short bit.

That is an additional proposal - but power supplies are really a technical
matter - they should really get the basic route for Airtrack sorted first I
reckon...

Doesn't the adjacent M25 have 'catenary'
lighting. Perhaps they should take away all lighting on that bit to
reduce environmental damage- or why just stop at removing lighting...

The phrase 'locking the stable door' etc springs to mind when discussing the
environment in that area, hemmed in as it is by the M25 and Heathrow
already.

Perhaps the local council might do well to look at examples such as the ECML
catenary over the Durham Viaduct, or the River Tweed's Royal Border Bridge,
and compare their wonderful local environment before launching into such a
pointless debate...

Paul S

On 21 Apr, 12:43, "J. Chisholm" wrote:
I thought the intention was to 'extend' Hex to Staines, to enable
interchange with Reading/Windsor lines. You can only do that if you 25kv
that short bit.

No, they're also investigating adding shoes to the HEx trains.

From the consultation brochu
"Three options for making the change from OHLE to third rail
electrification are currently being considered:
1) change over as close to the tunnel entrance as possible, while
trains are moving. It is possible that in this option the overhead
lines may not need to extend onto the SSSI at Staines Moor
2) change over from OHLE to third rail electrification at the new
Staines High Street station, while trains are stationary
3) run OHLE all the way to the existing Staines station. This option
would allow Heathrow Express services, which currently use OHLE, to
operate to the existing Staines station and is favoured by BAA for
that reason

In addition, the adaptation of the current rolling stock used by
Heathrow Express is being considered. If it is possible to adapt the
trains, the need to extend OHLE to the existing Staines station could
be avoided. "

http://tinyurl.com/464z9n

U

--
http://londonconnections.blogspot.com/
A blog about transport projects in London