Originally Posted by
787fan
outbound is same-plane LAX-SYD-MEL, inbound require changing planes
Not really - MEL-SYD-SFO is the same plane too! It changes flight numbers in SYD, and you will need to de-board (there's a 2 hour gap between arrival and departure).
The planes normally (baring IRROPS) do :
LAX-SYD-MEL-SYD-SFO and
SFO-SYD-LAX
Originally Posted by
787fan
how come MEL-SYD doesn't require re-clearing security? they treat it as domestic (with no 5th freedom) ?
All passengers in the international departure area need to have gone through security in Australia. Passengers arriving from MEL already have been through security there, so there's no need to re-screen.