Tom Barry:
One other benefit of double-deck trains, by the way, is shorter train
lengths for the same capacity (which saves money on station lengths,
but not in the capacity of escalators etc.). That's at the expense of
dwell times, though, unless you do something really clever like having
double-height platforms with doors on the upper deck too (I like the
sound of that, actually).

J.R. Stockton:
At busy stations, there can be a lower-deck platform on one side of the
train and an upper-deck platform on the other side.

Tom Anderson:
Has this actually been done anywhere? Can i see pictures?

The upper deck would have to have doors that open about 8-10 feet
(2.5-3 m) above rail level. Which means that if those doors ever
opened outside a station, someone could fall out and break their neck.
I find it hard to believe that safety authorities anywhere would
accept that.

It's different for elevators, because the elevator shaft provides
protection. I used to work in a building with double-deck elevators.
If you worked on an even-numbered floor, to get there you boarded
from the ground floor. For odd-numbered floors you'd take the
escalator to the basement concourse to catch the elevator.

(As this was in Canada, the ground floor was also floor 1, which
seems to break the pattern; but floor 2 only existed in the lobby
area and was not served by the main elevators. Going back down,
you'd just have to take whichever deck arrived, and wouldn't have
a choice of whether you arrived at the ground or basement level.
Both decks had buttons for all floors they could reach; they
just didn't all work when you were on the ground or basement.
So trips between floors above ground were generally like using a
normal elevator.)
--
Mark Brader, Toronto This is a signature antibody. Please
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