Flight Suvarnabhumi Airport departs from Bangkok Suvarnabhumi Airport at 18:45 and arrives at Hanoi Noi Bai International Airport at 20:25.
The flighttime is about 1h 40m. The distance travelled ("as the bird flies"): 593 Km. So the average speed is roughly 356 Km.
The best day to arrive at Bangkok is Wednesday and it would be best to avoid Saturday, as prices are on average 161.95% higher than on Wednesday. (Average prices, based on 1247582 datapoints.)
We have a lot more statistics for flights VJ 904 and between Bangkok and Hanoi.
