Flight Kansai International Airport departs from Osaka Kansai International Airport at 12:35 and arrives at Seoul Incheon International Airport at 14:25.
The flighttime is about 1h 50m. The distance travelled ("as the bird flies"): 1002 Km. So the average speed is roughly 547 Km.
The best day to arrive at Osaka is Thursday and it would be best to avoid Sunday, as prices are on average 498.59% higher than on Thursday. (Average prices, based on 6335830 datapoints.)
We have a lot more statistics for flights JL 5213 and between Osaka and Seoul.
