On Apr 21, 6:11*pm, Boltar wrote:
On 21 Apr, 13:55, Andy wrote:

(per car). Having every axle motored generally allows better
acceleration, if all other things are equal. It will be interesting to
see how the Northern stock performs, once the trains are used to their
full potential.

Why arn't they using it already, what are they waiting for? The A
stock was doing 60 mph back in the 1960s with no ATO in sight.

B2003

Basically because the signalling can't cope. Thing's like stopping
distances and overlaps are set up for the 1959 stock. A 1995 stock
train approaching a signal more quickly than a 1959 stock train leads
to potential problems with the overlap distances; as does accelerating
more quickly from a platform. The original plan was for a replacement
of the trains to be followed immediately by replacement of the
signalling. However, the money for the signalling and track upgrade
was cut, leading to new trains which had to be detuned to run safely
on old signalling setup.

What I don't know is if the 1996 on the Jubilee line is also detuned
compared to maximum performance, awaiting introduction of new
signalling, or whether the history of most of the line being part of
the Metropolitan means that the signalling is better setup for
'mainline' performance.