Originally Posted by
Slatye
Seems to me that if you stay in Class G airspace, you're absolutely fine to go without a Mode S transponder (or, for that matter, any transponder).
AIP ENR 1.6-7:
7. AIRCRAFT TRANSPONDER
7.1 Operation of SSR Transponders
7.1.2 Unless advised otherwise by ATC, pilots of Mode 3A or Mode S transponder equipped aircraft operating in Australian airspace must activate their transponders, and where a Mode C capability is also available it must be activated simultaneously with Mode 3A.
AIP GEN 1.5-13:
6.1.3 ADS-B Equipment
6.1.3.2 An aircraft, which is fitted for serviceable ADS-B transmitting equipment that complies with an approved equipment configuration, must operate the equipment continuously during the flight in all airspace at all altitudes unless the pilot is directed or approved otherwise by ATC.