Flight Changi Airport departs from Singapore Changi Airport at 09:30 and arrives at Perth Perth Airport at 14:40.
The flighttime is about 5h 10m. The distance travelled ("as the bird flies"): 1789 Km. So the average speed is roughly 346 Km.
The best day to arrive at Singapore is Thursday and it would be best to avoid Sunday, as prices are on average 239.34% higher than on Thursday. (Average prices, based on 225774 datapoints.)
We have a lot more statistics for flights SQ 223 and between Singapore and Perth.