Flight Huanghua International Airport departs from Changsha Huanghua International Airport at 22:40 and arrives at Chongqing Chongqing Jiangbei International Airport at 00:20.
The flighttime is about 2h 40m. The distance travelled ("as the bird flies"): 734 Km. So the average speed is roughly 275 Km.
There is an 1 hour time difference between Changsha and Chongqing