On Tue, 25 Sep 2007, MIG wrote:

On Sep 25, 11:30 am, Tom Anderson wrote:
On Tue, 25 Sep 2007, MIG wrote:
On Sep 25, 9:01 am, MIG wrote:
On Sep 25, 1:07 am, Tom Anderson wrote:
On Mon, 24 Sep 2007, Colin Rosenstiel wrote:
(Tom Anderson) wrote:
On Sun, 23 Sep 2007, Colin Rosenstiel wrote:

the aborted 9 car train experiment.

9 cars? What? Where? When? How?

The 1938 stock book I quoted from last night described the
experiment as "something that seemed like a good idea at the time"
with the implication that the author thought they were stark
staring bonkers to have tried it!

Ha! Sounds about right. Surely hardly any of the central network
would have been 9-car, so where did they think the passengers in
those rear two cars would be going?

I've been trying to make sense of it as well, and I think it must
have been a kind of overlap, ie a couple of coaches not opened
between a suburb and somewhere in the centre, and then maybe two
others going out of use at the same time, having been emptied in the
first half of the centre.

Or filled with people heading for the opposite suburb of course.

True. How much demand is there for trips from north of Golders Green to
south of Clapham? Not a lot, i'd have thought.

That's not what I meant. Two cars in use could deliver people at
stations up to Tottenham Court Road, while filling up at Euston, TCR etc
with people who would then have to stay on till a suburb.

Which, according to John's transcript (cheers John!) is roughly what
happened. Good thinking you! Sort of, anyway - i think you might be
suggesting a scheme where the front two cars (say) serve all stations to
Tottenham Court Road, and the rear cars all stations from Leicester Square
onwards, whereas it seems that what they did was have the rear two bonus
cars serve TCR only, with all others being served by the front two. Also,
due to the lack of 9-car ways out to the south, it seems the bonus cars
just emptied out in the middle of town, and didn't take anyone anywhere.

A third alternative would have been a skip-stop scheme, with, say, the
front two cars serving Archway, Kentish Town, Mornington Crescent, Warren
Street, Tottenham Court Road, Charing Cross, and Waterloo, and the rear
two Tufnell Park, Camden Town, Euston, Goodge Street, Leicester Square,
Embankment, and Kennington. I guess which of all these alternatives you
choose depends on the pattern of use - if TCR gets masses more passengers
than the other stations, then the plan as implemented makes the most
sense. Otherwise, i think the skip-stop scheme provides the most capacity
in town, as it lets both end pairs of cars be used for local trips,
whereas the switchover scheme basically means the up-to-TCR cars will be
empty south of TCR.

The limiting case of the skip-stop scheme would be to run fourteen-car
trains, with no cars serving all stations, and effectively have two
separate lines running down one set of rails. They do this (or have done
it) in New York, but there, they at least have the sense to use entirely
separate trains for the two service patterns! I think this might even work
for commuter traffic, as all the central London stations are close
together; Camden Town / Mornington Crescent, Euston / Warren Street,
Goodge Street / TCR / Leicester Square, Charing Cross / Embankment. It
only fails for people wanting to go from the south-of-Highgate suburbs to
the one of Euston or Waterloo that isn't in their pattern. Or coming from
Archway or Kentish Town and wanting the Bank branch (and not wanting to
wait for a direct train).

Actually, you can do better than that - 21-car trains with a three-phase
stopping pattern. The limit is actually a 196-car train with a 14-phase
stopping pattern, one entire set of seven cars for each station south of
Highgate, but i'm not entirely sure the suburban platforms are long enough
for that ...

However, this theory is scuppered by the lack of platforms in the south.

Yes.

I think the nine-car trains actually went round the Kennington loop.

Which sort of makes the lack of platforms in the south okay. If they could
have lengthened Kennington, it would have been pretty good. Aha! Or
stopped at the down platform as normal, and made a bonus-type stop at the
up platform - that way, everyone gets a chance to get out, and you have
the bonus cars running non-stop from Kennington to TCR (or whatever your
pattern implies), helping handle the transfer traffic from Bank trains.
You have to take passengers round the loop, though - was/is that allowed?

tom

--
There's no future.