Flight Tan Son Nhat International Airport departs from Ho Chi Minh City Tan Son Nhat International Airport at 01:00 and arrives at Busan Gimhae International Airport at 07:50.
The flighttime is about 4h 50m. The distance travelled ("as the bird flies"): 2736 Km. So the average speed is roughly 566 Km.
There is an 2 hour time difference between Ho Chi Minh City and Busan