Flight Suvarnabhumi Airport departs from Bangkok Suvarnabhumi Airport at 22:45 and arrives at Ho Chi Minh City Tan Son Nhat International Airport at 00:35.
The flighttime is about 1h 50m. The distance travelled ("as the bird flies"): 660 Km. So the average speed is roughly 360 Km.
The best day to arrive at Bangkok is Thursday and it would be best to avoid Friday, as prices are on average 124.8% higher than on Thursday. (Average prices, based on 6484930 datapoints.)
We have a lot more statistics for flights VN 602 and between Bangkok and Ho Chi Minh City.