Flight International Airport departs from Osaka International Airport at 10:00 and arrives at Tokyo Narita International Airport at 11:15.
The flighttime is about 1h 15m. The distance travelled ("as the bird flies"): 556 Km. So the average speed is roughly 445 Km.
The best day to arrive at Osaka is Wednesday and it would be best to avoid Monday, as prices are on average 38.16% higher than on Wednesday. (Average prices, based on 433698 datapoints.)
We have a lot more statistics for flights NH 20 and between Osaka and Tokyo.