Flight Narita International Airport departs from Tokyo Narita International Airport at 16:40 and arrives at Fukuoka Fukuoka Airport at 18:50.
The flighttime is about 2h 10m. The distance travelled ("as the bird flies"): 1119 Km. So the average speed is roughly 516 Km.
The best day to arrive at Tokyo is Tuesday and it would be best to avoid Friday, as prices are on average 194.5% higher than on Tuesday. (Average prices, based on 1118107 datapoints.)
We have a lot more statistics for flights JQ 517 and between Tokyo and Fukuoka.