Just to let you know that between Barnes Bridge and Hounslow, the only
two stations that require SDO (Selective Door Opening) are ISLEWORTH
(up and down) and KEW BRIDGE (down only). Syon Lane is able to fit an
8 car 450.
Only 2 possible reasons I can think of at the moment for using 4 car
lock out a
1). Reduces complexity. If you could lock on different numbers of
coaches, this adds complexity to the system (more things to go wrong).
And it would be hard to get to each location during rush hour
services.
2). Less chance of the guard making a mistake and opening too many
coaches. Guards are human after all (like rest of us).

Freddie

On Mon, 31 Jan 2005 17:38:27 GMT, "Richard J."
wrote:

wrote:
k wrote:
On 15 Dec 2004 16:39:14 -0800, (S. Endon-Lee)
wrote:



1) How come it wasn't possible to lock out only the rearmost car's
doors? This would be more useful.

2) Surely the platform lengths were known - so why build trains
that are too long, and don't easily accommodate themselves to
short platforms by locking out the minimum number of doors
necessary?

3) How long are these trains compared to the older (?317) stock
(or even the slam door stock)?

4) I noticed that the resignalling work a few years ago seemed to
move the stop point (the 8 car/4 car black signs with white 4 or
8 numeral) on several platforms, wasting some of the platform
length - why was this? Surely it makes sense to use all the
platform available?

5) What will the long term solution be? I'm not at all sure the
Isleworth platform can be extended easily or cheaply, as the
station fills the space between two bridges - it looks like major
bridge rebuilding/widening would be needed. Barnes has only
recently been resignalled and had platform work so I'm surprised
it's too short.


Does anyone have the answers to these questions as the thread went
a bit adrift :-)

Could anyone favour the group with a reply?

I admit I got it wrong, not knowing that the previous stock was
'455' stock, but the rear 4 carriages are still being locked out at
Kew Bridge, Syon Lane and other stations. Are the Desiros intended
to be upgraded to allow locking out of only some of the rear four
carriages? Thanks,

I haven't got answers to all your questions (yet), but I agree it's daft
to have to lock the doors on 4 cars just because the Desiro cars are
very slightly longer than the 455s or slam-door cars. I suspect that
SWT may revert to 455s on the Hounslow Loop once they have been
refurbished, as it's not sensible to have 1st class seating on
short-distance suburban workings like Waterloo-Hounslow-Waterloo.
Weren't the Class 450 Desiros always intended for *outer* suburban work?

I'm sure the commuters returning home on a wet evening to Syon Lane
don't appreciate having to walk half the length of an open platform to
get to the exit. It would be more useful to lock out the front 4 cars
there, but the starter signal position prevents that, or at least it
would do on the probably rare occasions that it's red.