Flight Tribhuvan International Airport departs from Kathmandu Tribhuvan International Airport at 14:00 and arrives at Delhi Indira Gandhi International Airport at 15:50.
The flighttime is about 2h 20m. The distance travelled ("as the bird flies"): 917 Km. So the average speed is roughly 393 Km.
There is an 0.5 hour time difference between Kathmandu and Delhi