For info on 'Operation Highball', read on.....
Operation Hibal WATCH ONLINE FREE FULL LEINGHT MOVIES DOCUMENTARY FLICK
(sic)....
From 'memory'....not always 'that' reliable these days....Op. HIBAL were also launched ex Mildura in the early 70's....
'74 or so (?).....can remember NOTAMS about them...sort of....
"Aircraft in the Mildura area, traffic is/was/be aware of, a bloody big balloon...."
Cheers