While en tour over the weekend visiting Paris – as one does
at this time of the year – I used the city’s Metro network to get around the
sights. And, following all the heat generated by London’s occasional Mayor
Alexander Boris de Pfeffel Johnson over the
idea of automatic operation for London’s Underground, I also checked out
how this is accomplished in Paris.
Odd French technology (not an automatic route this)
And the answer is, it’s done in a way that will be impossible to replicate over almost all of the London system. Paris now has two Metro lines operating on automatic – Line 1 was the example touted to Londoners of how to convert an existing route, with Line 14, the newest on the system, having followed more recently. Both these lines are simple end to end operations.
Moreover, they have little or no exposure above ground: Line
1 comes into the open briefly at Bastille, and when it crosses the Seine, and
that is that. There is nothing on the scale of the surface sections of Tube and
Sub-surface Lines (SSLs) in London. And both these lines have platform doors at
all stations (the 14 was built with them). This, though, does not hamper
ventilation.
That is because Line 1 runs in double track tunnel (rather
like the SSLs in London), and so there is none of the constraint that tube
tunnels would impose. Platform doors on older Tube lines would make ventilation
of the stations more difficult. And then there is the particularly French
running gear, which most certainly does not exist anywhere on the London
system.
Some lines on the Paris system have been adapted to use
rubber-tyred trains: these still have conventional tracks, but only for
guidance. This is supposed to produce a quieter and smoother ride, but modern
suspension systems for conventional rail vehicles do just as well. The
automatic lines use this system. So is Bozza looking to bring that to the UK?
He doesn’t know. He’s
shooting from the hip.
So how do the automatic trains perform? The acceleration and
braking is often unsubtle in the way that Automatic Train Operation (ATO) was
on the Central Line when first used over a decade ago. There are occasional “pathing stops” as trains are ordered to
wait at stations to even out the gaps between them. And the ones on Line 1
suffer from braking snatch, often juddering to a stop.
To be fair, ATO on the Tube does better than that, so the
version used in Paris probably needs a couple of software revisions to improve
things. And the punters seem to like sitting up front, even though there is
nothing to see for most of the journey. But London doesn’t have simple end to
end lines in double track tunnel with almost all the route underground or
easily fenced off.
So the comparison with Paris is largely meaningless. No change there, then.
1 comment:
The question, then, is where might one find a driverless ATO line that's mostly above ground, features several single-bore tunnels, has no PEDs, and a multiplicity of junctions and routes?
Ah.
Post a Comment