Flight Sydney Airport departs from Sydney Sydney Airport at 15:20 and arrives at Perth Perth Airport at 18:20.
The flighttime is about 5h 00m. The distance travelled ("as the bird flies"): 3917 Km. So the average speed is roughly 783 Km.
There is an 2 hour time difference between Sydney and Perth
The best day to arrive at Sydney is Saturday and it would be best to avoid Wednesday, as prices are on average 216.8% higher than on Saturday. (Average prices, based on 7213194 datapoints.)
We have a lot more statistics for flights QF 651 and between Sydney and Perth.
THB