In message . li, Tom
Anderson writes

Tripcocks are present at all home signals on LUL lines.

You meant to say:

Tripcocks are present at all stop signals on LUL lines.

Didn't you?

Naturally.

Does 'stop signal' mean 'signal capable of telling a train to stop', ie
anything that can go red, as opposed to route indicators etc? If so, i
hadn't realised that, i stand educated, that's a very good thing, and
i'm surprised there wasn't something along those lines protecting the
wrong-way move that was possible here, some sort of always-on tripcock
alongside the board saying YOU ARE GOING THE WRONG WAY.

Basically yes. Of course a route indicator will always have a stop
signal with it (as in a "you can now go and you are going to go this
way" signal).

If a line is not intended for bi-directional running (as it isn't in the
case under review) there is no need to provide signals for a route that
isn't, in normal circumstances, able to be used. I say normal
circumstances as there is always the possibility of doing a Wrong
Direction Move, however in the case of a WDM there is paperwork involved
and a whole safety procedure to follow so it isn't something that's done
lightly. I've never done one in anger in 9 years.

One additional item of protection that has been provided after some
incidents in the deep and distant past is fixed red lights as a reminder
at strategic places where an unusual move might possibly be made. I am
aware of at least one at Kings Cross WB Picc at the tailwall end that
has an associated train stop. The train stop automatically lowers when
a train approaches from the correct direction to avoid the train being
rear tripped. It then rises again as the train is fully berthed so that
any attempt to change ends and drive the other way will result in the
train being front tripped. I couldn't possibly comment on whether this
move has been attempted in the past whistles innocently (No! not me
)
--
Steve Fitzgerald has now left the building.
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