Found some more info on this -
The 727—200 LR, was a graceful and stunningly quick airliner. It did the routes between the eastern capitals and Perth in as much as an hour less time than today’s airliners, in part through a faster airframe, including 35 degree swept back wings. Boeing 727s flew the Sydney-Melbourne route some 20 minutes faster than today
The first Boeing -727 commercial flights occurred on November 2 1964 between Sydney and Melbourne, when VH-RME made the journey in a record 47 minutes 55 seconds. A lot faster than today.
The LRs were registered VH-ANA, B / E/ F
The first 727-277LR arrived on June 11, 1981 wearing Ansett's new Southern Cross livery which featured an all white fuselage and a dark blue tail emblem with a stylised Southern Cross emblem. This was the new face of an Ansett that was without its founder Reg Ansett for the first time.