Flight Tan Son Nhat International Airport departs from Ho Chi Minh City Tan Son Nhat International Airport at 22:40 and arrives at Melbourne Melbourne Airport at 11:00.
The flighttime is about 9h 20m. The distance travelled ("as the bird flies"): 5004 Km. So the average speed is roughly 536 Km.
There is an 3 hour time difference between Ho Chi Minh City and Melbourne