The government, in their infinite wisdom, do not allow hecs to cover flying training for undergraduate degrees.
The work around is then either:
1. use VET Fee-Help from the VET or TAFE sector (but watch out for the costs of the loan)
OR
2. use Fee-Help which is available for university approved Postgraduate courses such as a Graduate Diploma or Graduate Certificate
I looked into the Fee-Help thingo at one stage and there is a lifetime max loan of up to about $87K . You have to pay it back when your income exceeds some limit and it is recouped by the ATO in the same way as Hecs
'tis all explained at
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