Flight Incheon International Airport departs from Seoul Incheon International Airport at 09:35 and arrives at Osaka Kansai International Airport at 11:20.
The flighttime is about 1h 45m. The distance travelled ("as the bird flies"): 1002 Km. So the average speed is roughly 573 Km.
The best day to arrive at Seoul is Saturday and it would be best to avoid Wednesday, as prices are on average 185.58% higher than on Saturday. (Average prices, based on 2302832 datapoints.)
We have a lot more statistics for flights KE 723 and between Seoul and Osaka.
