Flight Suvarnabhumi Airport departs from Bangkok Suvarnabhumi Airport at 20:55 and arrives at Chiang Mai Chiang Mai International Airport at 22:20.
The flighttime is about 1h 25m. The distance travelled ("as the bird flies"): 221 Km. So the average speed is roughly 156 Km.
The best day to arrive at Bangkok is Monday and it would be best to avoid Saturday, as prices are on average 95.33% higher than on Monday. (Average prices, based on 10643719 datapoints.)
We have a lot more statistics for flights FD 4102 and between Bangkok and Chiang Mai.