Call it dual.
The airport infrastructure is still fed govt owned, but leased ie washed off their hands to the BNE airport corp, a private business to operate.
"BAC purchased Brisbane Airport from the Fed Government in 1997 for $1.4 billion under a 50 year lease..." according to the Brisbane Airport website.
The airport fire service, might still be govt owned.
It is, still owned by Air Services Aust, a federal government agency.
As would be Air Services Aust who operate the tower ops.
Lots of fingers in the airport $ pie.
Then, not to mention too, we have the 3 hotels in proximity, who also make $ out of late incoming or very early outgoing pax.
Its a million $ industry.