Flight Indira Gandhi International Airport departs from Delhi Indira Gandhi International Airport at 16:30 and arrives at Kolkata Netaji Subhas Chandra Bose International Airport at 18:40.
The flighttime is about 2h 10m. The distance travelled ("as the bird flies"): 1262 Km. So the average speed is roughly 582 Km.
The best month to arrive at Delhi is August and the most expensive month to fly is April. (Average prices, based on 556 datapoints.)
We have a lot more statistics for flights 6E 6415 and between Delhi and Kolkata.