On Wed, 25 Apr 2012 12:28:48 +0100
Paul Corfield wrote:
AFAIK there are no plans for a new type of signalling on the sub surface lines
so they could easily have fixed what was there first then bought new trains.

There is a huge project in place to replace all of the sub surface
signalling. It was originally tied in with the fleet replacement but
was retendered after the collapse of Metronet.

I said new type of signalling. I thought it was just replacing what was
there with new equivalents. Maybe not.

Traction current supply and current rails for the more powerful trains

So the new trains are inefficient overweight lardbutts like the trains on the
3rd rail network? I can't believe aircon makes so much difference to the power
usage that they need to upgrade the supply.

Well the new Vic Line signalling was installed and patched behind the
existing system to allow a phase of new and old rolling stock running
together. As you know once enough of the new trains were in place a
phased switchover started from Walthamstow and has now reached
Brixton. I think the old system is now completely switched off.

I was thinking more of the problems with the trains themselves. Endless door
issues and random failures.

There are significant challenges in getting the SSL signalling in
place but getting the new trains into service does reduce the need to
fit ATO kit on old stock which would then have to be removed when the
old stock was withdrawn.

ATO on the Circle? That'll be interesting to see!

B2003