Tom Anderson wrote:
On Sat, 21 May 2005, TheOneKEA wrote:

Tom Anderson wrote:

I might have lost the plot, but that seems to make no sense
whatsoever - making the line longer wouldn't have capacity
implications. You could run trains at exactly the same frequency (if
you had a few more), so as far as Brixton is concerned, it wouldn't
be any different. Or am i being stupid?

Extending the line and adding more stations increases the number of
passengers that the line must carry.

Right.

To ensure that loadings remain even, train frequency must be increased
to compensate, which is the problem at hand.

Okay. I don't understand that - why does the frequency have to increase?

Because, given that the vast majority of passengers are travelling to
the central area (say Victoria - KXSP), the passengers from the new,
extension stations are using capacity in the central area which isn't
available.

The Victoria line is essentially full at the moment. If any new stations
are added (e.g. to the south), the trains will already be partly filled
up by the time they reach the current start of the line (e.g. Brixton).
With an extension, the point where they become totally full will be
further out than before (e.g. Vauxhall as opposed to Victoria), and so
passengers further in than this new "full point" (e.g. Pimlico) will
simply be unable to board the trains as there will be no available
capacity. Therefore frequency must be increased to allow the existing
passengers in the central area to board the trains.

--
Dave Arquati
Imperial College, SW7
www.alwaystouchout.com - Transport projects in London