Flight Kansai International Airport departs from Osaka Kansai International Airport at 21:10 and arrives at Tokyo Narita International Airport at 22:20.
The flighttime is about 1h 10m. The distance travelled ("as the bird flies"): 582 Km. So the average speed is roughly 499 Km.
The best day to arrive at Osaka is Saturday and it would be best to avoid Monday, as prices are on average 128.25% higher than on Saturday. (Average prices, based on 8619031 datapoints.)
We have a lot more statistics for flights JL 228 and between Osaka and Tokyo.
