Civil Aviation Regulation 143 is what you want. It is
verboten unless you get it in writing from CAsA that you can.
CIVIL AVIATION REGULATIONS 1988 - REG 143
Carriage of firearms
************ (1)* A person, including a flight crew member, must not carry a firearm in, or have a firearm in his or her possession in, an aircraft other than an aircraft engaged in charter operations or regular public transport operations.
Penalty
10 penalty units.
************ (2)* An offence against subregulation*(1) is an offence of strict liability.
Note
******** For strict liability , see section*6.1 of the Criminal Code .
************ (3)* It is a defence to a prosecution under subregulation*(1) if the person had the written permission of CASA to have the firearm in the aircraft.
Note
******** A defendant bears an evidential burden in relation to the matter in subregulation*(3) (see subsection*13.3(3) of the Criminal Code.