Flight Heathrow Airport departs from London Heathrow Airport at 16:25 and arrives at Mumbai Chhatrapati Shivaji International Airport at 06:50.
The flighttime is about 9h 55m. The distance travelled ("as the bird flies"): 8456 Km. So the average speed is roughly 853 Km.
There is an 4.5 hour time difference between London and Mumbai