Just to further muddy the murky waters, wasn't one of the issues with 'Army Aviation' back in the 70's that the Army paid for and owned the helicopter support fleet, but the RAAF operated them?
I thought that the Chooks were bought from the Army budget, regardless that the RAAF drove them
No, not so. The Iroquois were purchased by the RAAF from about 1962, with deliveries of UH-1B/D/H in batches over the next decade. Paid for and operated by RAAF. Same as Chinook, paid for and operated by RAAF. Like an observation on another thread, even though both types - and then the first Blackhawks - had "RAAF" or "AIR FORCE" painted on the sides, the media always referred to them as "army helicopters". Finally around 1989, the Blackhawks and Hueys were handed over to the Army. Then the CH-47C was retired from the RAAF.