Re: Beresfield Accident Findings

["Tezza" <tezza@atinet.com.au>]

Chris Grace wrote in message ...
>Tezza (tezza@atinet.com.au) wrote:
>: Eddie Oliver wrote in message <354BB0CF.7CB0@efs.mq.edu.au>...
>: >Tezza wrote:


>: >> Why would locos be hitting pieces of coal? It's actually carried in
the
>: >> trucks behind the locos, not alongside the track. And minimal damage
>: caused by emergency braking (I've never seen any), would be far better
than a
>: >> freight train running into a passenger train.


>: >Are you serious?


>:Sarcastic.

>: >Are you trying to tell us that coal is so nicely confined to the hoppers
>: that none ever falls out?


>: It's fairly rare, there's more chance of it coming out of the bottom than
>: the top. All that'll come off the top is virtually dust, as the coal is
>: crushed, not in big lumps. Anything that did fall out would be way below
the
>: level of a trip. Landslides and rock falls would be a bigger worry on the
>: Illawarra and I've never heard of any of them tripping a train.

>I'm pretty sure that the trainstops used in NSW are the same ones used on
the
>London Underground, they are pretty standard Westinghouse gear.



>It has consistently been stated that the trainstops as used on LUL and
parts of
>NSW railways are not considered usable at high speeds (In this case so far
as I
>know 'high speed' means over around 35mph). Previous posters have described
>tripping when passing speed control trainstops at too high a speed, then
>resetting the trip once the train has stopped. If the train was moving too
fast
>to begin with, it is possible that either the trainstop or the trip would
be damaged
>by the impact, and this would mean that the rear of the train that had just
>tripped would be unprotected.


Apart from signals at stop and then detonators.

>Not only that, but the train which had tripped (and
>potentially destroyed its tripcock) would then have to run with it
isolated, and
>consequently with no protection at all.


Not being CityRail myself, is this allowed? Or would it go back to a depot
for repairs?

> which defeats the purpose of having it in the first place.


Not at all, it worked, it stopped the train, it did it's job. Better than
nothing at all.

>The other problem is that trainstops are electro-pneumatic. This isn't a
problem
>in London as the signalling and points are (or were) also electropneumatic
and
>consequently air supplies were available to operate them. I don't know if
the
>City Underground in Sydney is all electropneumatic or not, but even if it
isn't
>we're talking about a pretty restricted geographical area, and in any case
>traction current could presumably be used to drive compressors. I
>could imagine problems getting compressed air to every signal in
>non-electrified or country areas.



I don't know about the City Circle but I think most stops are
electro/mechanical (?).

>And, of course, trainstops are another maintenance problem. I have no idea
how
>they would fare in the open air in the country - they would obviously be
subject
>to vandalism,


More likely in the city than the country.

> and unlike a signal, this wouldn't be immediately obvious to
>drivers, so they'd have to be inspected frequently.



As is all track and equipment.