Flight Tribhuvan International Airport departs from Kathmandu Tribhuvan International Airport at 22:55 and arrives at Hong Kong Hong Kong International Airport at 05:25.
The flighttime is about 4h 30m. The distance travelled ("as the bird flies"): 3173 Km. So the average speed is roughly 705 Km.
There is an 2 hour time difference between Kathmandu and Hong Kong
