Flight International Airport departs from Doha International Airport at 09:40 and arrives at Kathmandu Tribhuvan International Airport at 16:45.
The flighttime is about 4h 05m. The distance travelled ("as the bird flies"): 3758 Km. So the average speed is roughly 920 Km.
There is an 3 hour time difference between Doha and Kathmandu
The best day to arrive at Doha is Tuesday and it would be best to avoid Wednesday, as prices are on average 177.33% higher than on Tuesday. (Average prices, based on 162605 datapoints.)
We have a lot more statistics for flights QR 646 and between Doha and Kathmandu.