Flight Don Mueang International Airport departs from Bangkok Don Mueang International Airport at 17:50 and arrives at Medan Kualanamu International Airport at 19:55.
The flighttime is about 2h 05m. The distance travelled ("as the bird flies"): 272 Km. So the average speed is roughly 131 Km.
The best day to arrive at Bangkok is Thursday and it would be best to avoid Tuesday, as prices are on average 80.63% higher than on Thursday. (Average prices, based on 479819 datapoints.)
We have a lot more statistics for flights QZ 157 and between Bangkok and Medan.