AIPA has already tried to get CASA on its delays in the Federal Court back in 2014 by funding an AIPA's member's case:
http://www.austlii.edu.au/cgi-bin/si...4%20FCA%201016
"There is no basis pleaded on which to conclude that the time between the receipt of the 2 November 2011 letter and the case conference on 22 March 2012 constituted an unreasonable delay in the process of CASA’s fulfilment of its statutory duties."
"...there may be a common law duty of care owed by CASA in some circumstances but, in the exercise of power and judgment under the CA Act in respect of the maintaining, enhancing and promoting the safety of civil aviation, CASA acts for safety of the public generally and not for the benefit of the person affected by that exercise."
Although I agree this is a different issue to delays caused by computer failures, staff shortages etc.