Flight Suvarnabhumi Airport departs from Bangkok Suvarnabhumi Airport at 18:55 and arrives at Mumbai Chhatrapati Shivaji International Airport at 21:55.
The flighttime is about 4h 30m. The distance travelled ("as the bird flies"): 3097 Km. So the average speed is roughly 688 Km.
There is an 1.5 hour time difference between Bangkok and Mumbai