Flight Heathrow Airport departs from London Heathrow Airport at 21:35 and arrives at Kuala Lumpur Kuala Lumpur International Airport at 17:50.
The flighttime is about 13h 15m. The distance travelled ("as the bird flies"): 10913 Km. So the average speed is roughly 824 Km.
There is an 7 hour time difference between London and Kuala Lumpur