Re: Train Accident in Blue Mountains

[billboltonREMOVE-TO-EMAIL@computer.org (Bill Bolton)]

"Dave Proctor" <daproc@spambait.umpires.com> wrote:

> are no train stops. Train stops improve safety (if they don't, wy are they
> all ovewr Sydney and Melbourne)

Trains stop will prevent certain types of accidents, specifically
those related to inadevertant passing of signals at danger where
traffic levels are high.  In that sense they enhance safety as far as
accidents which might arise from SPAD events.  

They have no effect at all on other types of accidents, i.e.
derailments, track obstructions, washaways etc etc and so do not
"improve" safety for those types of accident. 

> Having a level of safety that is less than what is possible makes it unsafe.

<sigh>

Centuries of saftey engineering practice says otherwise.

> Tripping through a signal *might* have served to slow the train down

If you are indeed as experienced with "tripping through" a syou cliam,
you will know how it is done. If the driver has come to rest in front
of the signal, the distance needed to trip through is perhaps 20
metres and after the brakes have reset he is technically free to drive
at whatever speed he wishes. 

> particularly since the train had stopped at Glenbrook station, and would
> have (presumably - notice, a presumption here) have received authority to
> pass the signal before leaving the station. Tripping through the signal
> *might* have meant that it would take extra time for the driver to reach the
> speed that the train was at at the time of collision

The signal is 30 metres past the station.  

> - thus, the speed that the train was at when the driver spotted the I-P
> would have been lower, and the impact *could* have been avoided or the
> impact reduced.

This is just silly.  You are building a "fairy castle" argument to
support a position that clearly would have no bearing on the speed of
the train at the point of the collision.

Cheers,

Bill