On Feb 24, 6:29*pm, "Zen83237" wrote:
"Recliner" wrote in message

...



"Zen83237" wrote in message

It seems a disgrace that of the Tubelines lines to get a new
signalling system first in the less than 10 year old Jubilee Line,
that quite frankly should have been built right in the first place.
Well at least the extention at least.
The Jubilee got completely new trains 20 odd years ago as well. Why
does the Jubilee get preferential treatment. Poor old Bakerloo line
gets stuffed. I accept with the Piccadilly line the new signally is not
much use
without the new trains.

The Jubilee line's trains are not much over a decade old, not 20 years.
But I'd much rather travel on the Picc's almost 35 year-old 1973 stock
trains, which are, arguably, still the nicest Tube trains on LU. But I
preferred their original transverse seating layout.

As for the Jubilee Line's signalling system, you probably remember that
the original intention to install moving block signalling was abandoned
when it became clear that it wouldn't be ready in time for the opening of
the Dome. A lower capacity conventional system was installed instead as a
stop-gap measure.

And why would moving block not have been ready in time. Not as if it hadn't
been done before on other railway syatems. Could they really not build a new
railway and not put a modern, state of the art signally system on it.
What are they putting on crossrail, semaphores?


Because the signalling system, as originally planned, would have
covered the whole line and the new trains wouldn't have needed to run
on a mixed system. As I understand it, the main problem was the
deadline of having the line open by December 1999, to serve the
Millenium Dome at North Greenwich. If TfL had had another year, it may
have been possible to get it all working reliably. Some of the
hardware was in place, but never got used in anger. The current fixed
block signalling was then overlaid on this, it was only with the new
signalling being installed that the original moving block hardware is
being removed.