Flight Brisbane Airport departs from Brisbane Brisbane Airport at 09:40 and arrives at Cairns Cairns Airport at 12:05.
The flighttime is about 2h 25m. The distance travelled ("as the bird flies"): 1295 Km. So the average speed is roughly 536 Km.
The best day to arrive at Brisbane is Thursday and it would be best to avoid Tuesday, as prices are on average 232.12% higher than on Thursday. (Average prices, based on 105620 datapoints.)
We have a lot more statistics for flights QF 708 and between Brisbane and Cairns.