Some phrase not being in AIP is of no consequence in Australian aviation RT these days. The pilot of so many ABCs - across the spectrum of operations - tell us that: “Alpha Bravo Charlie turns base”, which is like telling us that the pilot of ABC “likes seafood” and “thinks positively”.
Precision of communication continues to be important. In aviation, it helps others to know what you are doing NOW. When you broadcast: “I’m turnING base”; “I’m joinING downwind”; “I’m scratchING my arse”, others interpret that to mean you’re doing that thing NOW.
That’s why broadcasting: “ABC Joining Downwind” isn’t a good idea unless ABC is actually joining downwind when you tell the world you are, as demonstrated by the circumstances which led to
this ATSB investigation and report.