Flight Narita International Airport departs from Tokyo Narita International Airport at 11:30 and arrives at Seoul Incheon International Airport at 14:10.
The flighttime is about 2h 40m. The distance travelled ("as the bird flies"): 1555 Km. So the average speed is roughly 583 Km.
The best day to arrive at Tokyo is Thursday and it would be best to avoid Sunday, as prices are on average 538.87% higher than on Thursday. (Average prices, based on 3827057 datapoints.)
We have a lot more statistics for flights RS 706 and between Tokyo and Seoul.
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