Flight Changi Airport departs from Singapore Changi Airport at 17:00 and arrives at Shenzhen Shenzhen Bao'an International Airport at 21:15.
The flighttime is about 4h 15m. The distance travelled ("as the bird flies"): 1318 Km. So the average speed is roughly 310 Km.
The best day to arrive at Singapore is Tuesday and it would be best to avoid Thursday, as prices are on average 449.75% higher than on Tuesday. (Average prices, based on 125788 datapoints.)
We have a lot more statistics for flights ZH 9024 and between Singapore and Shenzhen.
