Flight Incheon International Airport departs from Seoul Incheon International Airport at 20:30 and arrives at Tokyo Haneda Airport at 22:50.
The flighttime is about 2h 20m. The distance travelled ("as the bird flies"): 1487 Km. So the average speed is roughly 637 Km.
The best day to arrive at Seoul is Saturday and it would be best to avoid Wednesday, as prices are on average 162.86% higher than on Saturday. (Average prices, based on 2526521 datapoints.)
We have a lot more statistics for flights JL 5256 and between Seoul and Tokyo.
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