Flight Suvarnabhumi Airport departs from Bangkok Suvarnabhumi Airport at 01:10 and arrives at Busan Gimhae International Airport at 08:30.
The flighttime is about 5h 20m. The distance travelled ("as the bird flies"): 3243 Km. So the average speed is roughly 608 Km.
There is an 2 hour time difference between Bangkok and Busan
THB
