Re: Bethungra Spiral

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

In article <37CF20D7.FD3B5F3E@omni.com.au> David Bromage <dbromage@omni.com.au> writes:
>Date: Fri, 03 Sep 1999 11:14:00 +1000
>From: David Bromage <dbromage@omni.com.au>
>Subject: Re: Bethungra Spiral

>Maurie Daly wrote:
>> The reduction in full load is (if we assume an NR class, 1750 tonnes down to
>> 1235 tonnes) ie we lose 515 tonnes of gross load , which translates into lost
>> revenue , approx $9800 of lost revenue (at 2.5 c/ntk) per train , all to save
>> 4.5 km in 960 km.
>> Makes no sense at all.

>Or you could add a banker at Junee.

>Cheers
>David


Yes you could , but adding and subtracting bankers along the way costs money 
and time, money in that you need an extra crew to get the bank engines back to 
Junee for the next train , and the delays caused by the adding and subtracting 
them.
This is not to say however than banking isnt a good idea and shouldnt ever 
happen.
Where banking allows a significant extra load to be carried and the banking is 
only needed for a short distance , ie the Adelaide Hills,then the extra 
revenue earnt by the additional load carried is more than offset by the 
banking costs.
Singling existing double track is usually done to save money in some way.
The most recent examples , ie Gresham to Newbridge and Wallerawang to Tarana
were done in part because the double line didnt carry enuf traffic to warrant 
it , but more so to eliminate double line block working and the requirement 
for manned signalboxes at the ends of the double line sections.
Also the sections where the singling were carried out were relatively short 
and didnt require the addition of extra crossing loops.

Coota - Junee is a totally differant animal.
The section is totally auto signals , no block working, no saving in 
signallers and more importantly is a long section ,56 kms which would require 
at least two intermediate crossing loops.
The savings just arnt there .

North of Coota the problems are differant but similar.
There are a number of manned signal boxes that really arnt needed, 6 in total 
but you can remove these without having to single track the entire section.
A large number of crossing loops would be needed to handle the widely 
differant running times of the variety of trains that use this section ,which 
would effectively mean some sort of CTC from Goulburn to Coota.
Simply not worth it currently.

MD
,