Flight Tan Son Nhat International Airport departs from Ho Chi Minh City Tan Son Nhat International Airport at 07:10 and arrives at Seoul Incheon International Airport at 16:35.
The flighttime is about 7h 25m. The distance travelled ("as the bird flies"): 2519 Km. So the average speed is roughly 340 Km.
There is an 2 hour time difference between Ho Chi Minh City and Seoul