40% of domestic passengers were related to international flights. Gone.
Business flying. About 20%. Gone at the moment, but probably massively reduced long term.
Melbourne-Brisbane-Sydney would probably represented something in the order of 60% of all pre CV flying. Basically gone too.
None of the other potential routes could possibly keep QF or Virgin going.
Future...TBA, but I don’t see it including any of the current players.
In the calendar year to 31 December 2019 - pre-COVID-19 - there were 61.28 million passenger journeys made in total on the regular public transport (air) routes measured by BITRE of the Australian Govt.
Of these, 9.18 million were on the Melbourne - Sydney route - so roughly 4.6 million each way; 4.82 million were BNE - SYD or SYD - BNE while 3.61 million were BNE - MEL/MEL-BNE.
So in total that's 17.61 million out of 61.28 million total journeys on the 'golden triangle', or 28.7 per cent of the total.
It would be higher had not the airlines gradually introduced more nonstop routes (such as MEL to PPP) in the last 20 years, or where they already had nonstops flying 'over BNE', increased the frequency of these.
Similarly, 30 years ago I doubt if I looked up printed timetables from then (which I have - but haven't cast an eye over) there would not have been any nonstop HBA up to SYD flights.
Also 30 years ago there would not have been as many FIFO workers engaged at mine sites in Pilbara/NW of WA. Where these routes are 'competitive' - two or more carriers - they're typically counted in the stats.
I am a little more optimistic than our aviator above re business travel as there remains a strong need for people to meet face-to-face but our man is correct that there'll be a downturn in such journeys.
If volumes decrease, airlines may be less willing (or unable profitably) to run so many point-to-point flights, so that may (counter-intuitively) result in a higher percentage of passengers using the 'golden triangle' routes and changing at such hubs more often to their destination.