As cockpit crew ? If so, would you have any details about how ?
There is no requirement in Australia to have an Australian passport, birth certificate, or citizenship to be a pilot. You can be American. There are still only four forces on the aircraft in Australia, money, bills, beer and sleep, in New Zealand the forces are different bro, money, bills, beer and sheep.
I would suggest that today as a flying instructor or pilot you can get a temporary long stay visa (Australian version of the E3), work in the industry, and then gain residency.
Why you would leave the US and go to Australia to fly is beyond me, unless it is to get yourself home.