Re: SAW/ASW - was Re: Computer Question - DTC

[mauried@commslab.gov.au (Maurie Daly)]

In article <+DhYOPbzPa+fZ5+8EmnJurfTa+Af@4ax.com> Yuri J Sos <steam4me@enternet.com.au> writes:
>From: Yuri J Sos <steam4me@enternet.com.au>
>Subject: Re: SAW/ASW - was Re: Computer Question - DTC
>Date: Thu, 16 Dec 1999 11:07:51 +1000

>On Wed, 15 Dec 1999 17:14:01 +1100, someone other than David Guymer
><davidmg@optusnet.com.au> wrote, and I selectively quote:

>> Had just about any alternative safe working system other than ASW or TO been
>> in place,even TS & T , this accident would not have happened.

>How many cases of trains being turned into other trains have happened
>in Victoria?  I'm told there was only one other collision a long time
>ago (like over 60 years ago).  One prang in 60+ years?

>How much would it cost to switch-lock every mainline siding in
>Victoria?  Who would pay for such a massive undertaking?

>       
>Regards

>Yuri
>-- 
>==================================
>Yuri J Sos
>Melbourne VIC AUS

>Reply to: steam4me@enternet.com.au

>Web site is located at
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Absolutely correct Yuri, this sort of accident in Victoria has in the past 
been extremely rare, simply because all points on main lines which were not 
switch locked , were staff locked , not key locked, so that if a driver had 
the staff he was guaranteed that all the intermediate points were locked
as you cant remove a staff from a unlocked staff lock.
(I beleive this also the case in other states,pls correct me if I am wrong.)

Its only the introduction of train order based safeworking (which up until 
the late 1970s that Vline would not even consider as it was deemed to be 
too unsafe.) that has required main line points to be key locked,and hence has 
introduced the potential problem of points being unlocked even though a driver 
has a valid train order .
This is a potential problem on all lines operated under train orders and why 
in the case of the TAR and CAR required all main line points to be fitted with 
point indicators.

There has to be some sort of procedure implemented in TO worked areas to ensure
categorically that an order cannot be issued if key locked points are unlocked.
Simply relying that everyone has done the right thing , ie locked all points 
just isnt good enuf,especially on main lines .


MD