On Sun, 14 May 2006 19:00 +0100 (BST), Colin Rosenstiel wrote:

When the designed the A stock, they built prototypes to try out new
ideas. The coaches before A stock were compartments and the A stock
was a kind of compromise between a normal underground carriage and a
compartment stock coach.

Not exactly. They converted parts of compartment stock vehicles for
trials but they weren't very close to the eventual A stock design I
don't think.

Why "S" for the new stock? The last surface` stock was "D".

I don't think it's supposed to be an alphabetical progression -
there's no B Stock. I've always thought (someone correct me if I'm
wrong) that A is for Amersham, C is for Circle, and D is for District.

The new stock will be common to the whole subsurface network - hence S
Stock.

Returning to the topic of interiors, there are good reasons why Met
trains have 60 seats per carriage while Circle trains have 32 (in
carriages of the same length) - Circle trains are less frequent and
more crowded, and mostly used only for short journeys, while the
average journey length on the Met is a *lot* longer. To me it seems
like madness that the new stock might all be fitted with a common
"compromise" interior that suits neither line well. From my
(admittedly armchair) point of view, it would be much better to
semi-permanently fit the stock for each line with an interior similar
to the current ones (or at least using them as a starting point). This
would require the stock to be long-term allocated to a particular
line, but I don't see why that would be a big problem, with the siting
of depots already suited to this arrangement. Short-term transfers of
stock between lines would still be possible - it would just mean the
odd train running around with an unsuited interior (rather than every
train on the Met/Circle). Long-term transfers would require an
interior refit, however.

In article ,
lid (asdf) wrote:

On Sun, 14 May 2006 19:00 +0100 (BST), Colin Rosenstiel wrote:

When the designed the A stock, they built prototypes to try out
new ideas. The coaches before A stock were compartments and the A
stock was a kind of compromise between a normal underground
carriage and a compartment stock coach.

Not exactly. They converted parts of compartment stock vehicles for
trials but they weren't very close to the eventual A stock design I
don't think.

Why "S" for the new stock? The last surface` stock was "D".

I don't think it's supposed to be an alphabetical progression -
there's no B Stock. I've always thought (someone correct me if I'm
wrong) that A is for Amersham, C is for Circle, and D is for District.

The new stock will be common to the whole subsurface network - hence S
Stock.

The stock before 1960 was lettered more or less in order (H was an
exception I forgot to mention). Since then a similar rule has applied.

Returning to the topic of interiors, there are good reasons why Met
trains have 60 seats per carriage while Circle trains have 32 (in
carriages of the same length) - Circle trains are less frequent and
more crowded, and mostly used only for short journeys, while the
average journey length on the Met is a *lot* longer. To me it seems
like madness that the new stock might all be fitted with a common
"compromise" interior that suits neither line well. From my
(admittedly armchair) point of view, it would be much better to
semi-permanently fit the stock for each line with an interior similar
to the current ones (or at least using them as a starting point). This
would require the stock to be long-term allocated to a particular
line, but I don't see why that would be a big problem, with the siting
of depots already suited to this arrangement. Short-term transfers of
stock between lines would still be possible - it would just mean the
odd train running around with an unsuited interior (rather than every
train on the Met/Circle). Long-term transfers would require an
interior refit, however.

It's completely stupid to try a compromise layout when such large
amounts of stock are involved and requirements differ so much.

Another lesson of history is the need for flexibility. Almost all modern
mainline stock can have its seating layout changed in pretty major ways
fairly easily. During its service life the new stock could change roles
in all sorts of ways.

--
Colin Rosenstiel