Flight Daxing International Airport departs from Beijing Daxing International Airport at 11:00 and arrives at Chengdu Chengdu Shuangliu International Airport at 13:55.
The flighttime is about 3h 55m. The distance travelled ("as the bird flies"): 1424 Km. So the average speed is roughly 364 Km.
There is an 1 hour time difference between Beijing and Chengdu