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Old July 5th, 2009, 04:48 PM posted to rec.travel.europe
Graham Harrison[_3_]
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Default Fast trains in Britain


"Mark Brader" wrote in message
...
James Silverton:
To settle arguments here, can anyone tell me what are the fastest
scheduled long distance trains in Britain? Are there any other trains
as
fast as the Chunnel train? How is timekeeping on the fast trains?


Graham Harrison:
The maximum permitted speed is 125mph but much track does not permit that
speed. Two train types were built (or intended) to operate faster but
they
have never been permitted to achieve their higher speed.

The Eurostar trains that operate London/Paris and Brussels via the
Channel
Tunnel have a maximum permitted 186 mph. Commuter trains using the same
tracks are currently being used in limited service and will operate to a
permitted maximum of 140 mph.


All of this is correct, except that "much track does not permit" is
perhaps a bit strong. There are three main lines in Britain today,
all built originally for lower speeds, that have been upgraded to
125 mph speed limits:

* East Coast Main Line, which leads north from London (King's Cross)
to York, Newcastle, and Edinburgh. I'm not sure exactly how far
north the 125 mph speed limit extends; maybe Newcastle.

* West Coast Main Line, which leads north from London (Euston) and
splits into different branches serving Liverpool, Manchester,
Birmingham, and Glasgow. Only tilting trains are allowed 125 mph
on this line, I believe from London as far as the Midlands (i.e.
Birmingham, Manchester, etc.) and some sections on the Glasgow route.

* Great Western Main Line, which leads west from London (Paddington)
to Reading, Bath, Bristol, and Cardiff. I believe the 125 mph
speed limit applies as far as Bristol. Trains capable of 125 mph
are used on the services to Exeter, Plymouth, and Penzance, but
only run at full speed on the short section as far as Reading.

The 186 mph route from London (St. Pancras) south to the Channel Tunnel,
now called High Speed 1, is much newer and was designed for that speed.

Other main lines generally have limits around 80-100 mph.
--
Mark Brader "Inventions reached their limit long ago,
Toronto and I see no hope for further development."
-- Julius Frontinus, 1st century A.D.

My text in this article is in the public domain.


The speed limits keep changing, much as they do on a road. Thus, 125 mph
is permitted from a few miles out of Paddington as far as just before
Reading then again from the other side of Reading to Didcot and then the
station is slower and it goes back to 125. Once you get to Wotton Basset
Junction and bear off left for Chippenham, Bath and Bristol the limit is
generally 100 or less. The same sort of pattern applies to the other two
lines you mention. One of the key characteristics of trains built to run
on "historic" lines is that however much upgrading has occurred they need
high power (horsepower/kwh) to accellerate away from lower speed areas and
station stops. Furthermore the three routes you chose represent a
surprisingly small part of the network as a whole.
hence my "much track does not permit" comment. And, to give a further
example one of the major junctions on the West Coast Main Line is at Rugby.
It has had the upgrade treatment and the speed limit through the station has
been raised from 20 to 80mph so an upgrade doesn't always allow operation at
125mph.

You are correct when you say that only the new "Pendolinos" on the WCML are
allowed to run at 125 (where permitted) - other trains are limited to 110.
A very recent rumour suggest some rumblings to increase the Pendolino limit
to 135 in places (they were built for 140) but don't hold your breath!