The Bletchley Fly-over
 

In article ,
(Robin9) wrote:

On 18/04/2016 06:41, Charles Ellson wrote:
--
More expensive, obsolete, less efficient and it's heading toward 25kV
territory.
--
just as the DC line does beyond Harrow?-
-
That was electrified over a century ago.-

Maybe that line was electrified over a century ago, but lots of the SE
(in the 90s?)

The line between Woking and Weymouth was electrified in
the 1960s at very low cost. I used to travel on that route
frequently. The third rail system did not stop those trains from

The 1967 electrification only extended to Bournemouth and ended steam on the
Southern Region. 12-car trains consisted of two 4-TC unpowered 4-car units
with a 4-REP tractor unit at the London end. A class 33 diesel took the
front 4-TC unit on to Weymouth and back. Some workings used class 73s with a
3-TC unit at the London end instead of the 4-REP. Later they converted more
4-REPs and extended the 3-TCs to 4 cars. Then the electrification was
extended to Weymouth in the 1990s and introduced the class 442 Wessex
electrics, re-using the REP traction motors which are higher-powered than
any others used on EMU stock.

--
Colin Rosenstiel

Thank for the correction. My memory playing tricks again! However,
coming back to the idea that third rail limits high speed running,
what speeds are routinely achieved between Southampton and
Woking?

Many thanks for that link. It gave me the information I needed.

Thanks to the good advice from posters here - thank you,
gentlemen, you're very well informed - I've had a look at a
1939 Ordnance Survey map of Verney Junction. This shows
clearly that the overhead railway bridge brought in the line
from Quainton Road.

Is there any means of inserting images into posts here?
I wanted to show the map of Verney Junction.

The Bletchley Fly-over and Verney Junction
 

In message , at 16:35:40
on Mon, 18 Apr 2016, remarked:

You can get a lot of 25 kV line covered from a
single feed.

Like Milton (north of Cambridge) to King's Lynn. Having single feed sections
quite that long has consequences, though.

As a point of information, it's two single feed sections, with a break
at Littleport. One of the reasons for having just one feed each is that
"the grid" is only available at Cambridge and Kings Lynn, and a new
major substation would be required at Littleport.
--
Roland Perry

The Bletchley Fly-over
 

In article ,
(Robin9) wrote:

;155038 Wrote:

The line between Woking and Weymouth was electrified in
the 1960s at very low cost. I used to travel on that route
frequently. The third rail system did not stop those trains from-

The 1967 electrification only extended to Bournemouth and ended steam on
the Southern Region. 12-car trains consisted of two 4-TC unpowered 4-car
units with a 4-REP tractor unit at the London end. A class 33 diesel
took the front 4-TC unit on to Weymouth and back. Some workings used
class 73s with a 3-TC unit at the London end instead of the 4-REP. Later
they converted more 4-REPs and extended the 3-TCs to 4 cars. Then the
electrification was extended to Weymouth in the 1990s and introduced the
class 442 Wessex electrics, re-using the REP traction motors which are
higher-powered than any others used on EMU stock.

Thank for the correction. My memory playing tricks again! However,
coming back to the idea that third rail limits high speed running,
what speeds are routinely achieved between Southampton and
Woking?

I think the lesson from the Eurostar before HS1 fiasco is that it's the
limitation on power drawn that is the speed problem. Downhill or on the
level they manage 100 MPH occasionally but 125 is but a distant dream.

--
Colin Rosenstiel

The Bletchley Fly-over
 

wrote:
In article ,
(Robin9) wrote:

;155038 Wrote:

The line between Woking and Weymouth was electrified in
the 1960s at very low cost. I used to travel on that route
frequently. The third rail system did not stop those trains from-

The 1967 electrification only extended to Bournemouth and ended steam on
the Southern Region. 12-car trains consisted of two 4-TC unpowered 4-car
units with a 4-REP tractor unit at the London end. A class 33 diesel
took the front 4-TC unit on to Weymouth and back. Some workings used
class 73s with a 3-TC unit at the London end instead of the 4-REP. Later
they converted more 4-REPs and extended the 3-TCs to 4 cars. Then the
electrification was extended to Weymouth in the 1990s and introduced the
class 442 Wessex electrics, re-using the REP traction motors which are
higher-powered than any others used on EMU stock.

Thank for the correction. My memory playing tricks again! However,
coming back to the idea that third rail limits high speed running,
what speeds are routinely achieved between Southampton and
Woking?

I think the lesson from the Eurostar before HS1 fiasco is that it's the
limitation on power drawn that is the speed problem. Downhill or on the
level they manage 100 MPH occasionally but 125 is but a distant dream.

No doubt that's true, but what does that have to do with infrequent
four-car EMUs on a 75mph max line?

The Bletchley Fly-over
 

In message , Robin9
wrote:
I was driving from Winslow along Verney Road. A railway
embankment came in on my right. Shortly before Verney
Junction the road goes under an old railway bridge. Now,
assuming the railway to my right is the trackbed of the old
route from Winslow and Bletchley, the bridge brought in the
line from Quainton Road.

Winslow Road passes under the Oxford-Bletchley line twice. Coming from
Winslow, you pass under it first he


t/data=!3m7!1e1!3m5!1sq-h5aDFlM_Ws1w6Ewtzz0A!2e0!6s%2F%2Fgeo1.ggpht.com%2
Fcbk%3Fpanoid%3Dq-h5aDFlM_Ws1w6Ewtzz0A%26output%3Dthumbnail%26cb_cli ent%3
Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D1 00%26yaw%3D135.65059%26
pitch%3D0!7i13312!8i6656

and then he


t/data=!3m6!1e1!3m4!1sxeG7CQGqki-hk8bWgNAc5A!2e0!7i13312!8i6656

The line from Quainton Road also used to pass over on a bridge, but the
bridge itself was demolished many years ago. This is what's left:


t/data=!3m6!1e1!3m4!1sho-SIgZeB3VeeGFc6K8yUg!2e0!7i13312!8i6656

--
Clive D.W. Feather | Home:
Mobile: +44 7973 377646 | Web: http://www.davros.org
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The Bletchley Fly-over and Verney Junction
 

On Sun, 17 Apr 2016 20:50:02 +0100, Neil Williams
wrote:

On 2016-04-17 19:22:12 +0000, Stephen Furley said:

Was Bletchley flyover intended to be electrified eventually? It has
concrete 'lumps' on the side of it which look as if they could have
been entended as mountings for OHLE structures.

I suspect that is indeed what they are for. Just thinking ahead, and
for EW Rail it might well be used.

On a related subject AIUI there are to be new platforms beyond the
eastern end of the flyover. But, my recollection is that the line
both curves and descend at that location. Do platforms not have to be
on straight, level track these days?

The Bletchley Fly-over and Verney Junction
 

On Mon, 18 Apr 2016 09:48:43 -0700 (PDT), wrote:

On Monday, 18 April 2016 17:41:04 UTC+1, bob wrote:
Recliner wrote:
Charles Ellson wrote:
On Sun, 17 Apr 2016 18:29:31 -0500, Christopher A. Lee
wrote:

On Sun, 17 Apr 2016 20:56:35 -0000 (UTC), Recliner
wrote:


What's wrong with just using 3rd rail beyond Amersham,

More expensive, obsolete, less efficient and it's heading toward 25kV
territory.

Much *cheaper*, surely? Less efficient, yes, but why should it matter that
it's headed towards 25kV territory?

The high cost of DC 3rd rail comes from the need for more complex and far
more frequent substations. You can get a lot of 25 kV line covered from a
single feed.

True, but how does that compare to the costs of rebuilding
dozens of bridges and tunnels on a line?

If memory serves, after the construction of the GC London Extension,
Metropolitan Railway trains were out of gauge north of Quainton Road
on the GC. They were too wide. OTOH, GC trains were out of gauge
between Finchley Road and Baker Street, they were too tall. I suspect
running 25kV out of Marylebone would not be especially challenging.
The structurer gauge being quite generous.