Camel Squadron
747 carries 25 extra business class seats over the 777-300.
Thats $87.5k extra revenue per flight. Daily return flights = up to $64m pa in extra revenue.
Using your Mel, Syd, Bris example would equal up to $192m per year in extra revenue.
Thats before even considering that the 747's have no remaining capital value whereas the 777 would cost as much as $300m each which needs to recouped. Lets keep it real simple, 6 777, 15 year life = $120m in capital costs per year that need to be recouped on a straight line basis ignoring the time value of money.
Revenue's not the whole issue and depreciation's only part of the cost puzzle. How does the operating cost per ASK compare between the 747 and the 777 or even the A330 or A380 over the same sectors?