Flight Chiang Mai International Airport departs from Chiang Mai Chiang Mai International Airport at 21:25 and arrives at Kunming Wujiaba International Airport at 23:40.
The flighttime is about 1h 15m. The distance travelled ("as the bird flies"): 439 Km. So the average speed is roughly 351 Km.
There is an 1 hour time difference between Chiang Mai and Kunming