Flight Netaji Subhas Chandra Bose International Airport departs from Kolkata Netaji Subhas Chandra Bose International Airport at 11:35 and arrives at Kathmandu Tribhuvan International Airport at 13:30.
The flighttime is about 1h 25m. The distance travelled ("as the bird flies"): 344 Km. So the average speed is roughly 243 Km.
There is an 0.5 hour time difference between Kolkata and Kathmandu