Flight Brisbane Airport departs from Brisbane Brisbane Airport at 18:45 and arrives at Perth Perth Airport at 22:20.
The flighttime is about 5h 35m. The distance travelled ("as the bird flies"): 4143 Km. So the average speed is roughly 742 Km.
There is an 2 hour time difference between Brisbane and Perth
The best day to arrive at Brisbane is Saturday and it would be best to avoid Monday, as prices are on average 106.1% higher than on Saturday. (Average prices, based on 313650 datapoints.)
We have a lot more statistics for flights QF 941 and between Brisbane and Perth.