CIVIL AVIATION ACT 1988 - SECT 20A
Reckless operation of aircraft
(1) A person must not operate an aircraft being reckless as to whether the manner of operation could endanger the life of another person.
(2) A person must not operate an aircraft being reckless as to whether the manner of operation could endanger the person or property of another person.
Penalty: 5 years
Plenty of other Commonwealth and State charges that would have seen higher penalties but this was probably the most specific charge for the offences committed. "Lucky" I think.