Flight Kansai International Airport departs from Osaka Kansai International Airport at 10:00 and arrives at Ho Chi Minh City Tan Son Nhat International Airport at 13:45.
The flighttime is about 5h 45m. The distance travelled ("as the bird flies"): 3399 Km. So the average speed is roughly 591 Km.
There is an 2 hour time difference between Osaka and Ho Chi Minh City