Flight Kansai International Airport departs from Osaka Kansai International Airport at 13:10 and arrives at Seoul Incheon International Airport at 15:00.
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 Saturday and it would be best to avoid Thursday, as prices are on average 127.03% higher than on Saturday. (Average prices, based on 5449202 datapoints.)
We have a lot more statistics for flights LJ 234 and between Osaka and Seoul.
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