Kolkata: The proposed Kalyani airport cannot function alongside NSCBI Airport in Dum Dum, a veteran aviator said, pointing out that the alignment of the runways at the two airports, 35km apart, would lead to conflicts in aircraft movements and pose a threat to flight safety.Retired senior flight captain Sumanta Roy Chowdhury, who has flagged the issue with the civil aviation ministry and Directorate General of Civil Aviation (DGCA), said the proposed airport in Kalyani falls on the extended centre line of the primary runway at the Kolkata airport, increasing the likelihood of accidents involving traffic at both airports.“If the two airports operate simultaneously, it will be extremely challenging and risky for pilots as well as controllers. If a flight were to take off from Kalyani, it would come within 1,000 ft of a flight descending to land at the Kolkata airport. Such movements will constantly set off a collision-avoidance alarm in the aircraft,” said Roy Chowdhury, who had joined others in opposing the setting up of a flight school in Kanchrapara about 30 years back for the same reason. That plan was subsequently shelved.The rate of descent for flights approaching Kolkata is around 1,500-2,000 ft per minute when they are over Kalyani, while the rate of ascent for a flight taking off from Kalyani will be around 1,000 ft per minute.The proposed airport was announced in the 2026 state budget to address capacity constraints at the Kolkata airport, reduce congestion and improve regional air connectivity.In a communication to the land and land reforms department in June, chief secretary Manoj Pant had said the Kalyani project was being planned on the lines of Noida International Airport in Jewar and Navi Mumbai International Airport, pointing out that there was no scope for expansion of the Kolkata airport.Thereafter, the registration department imposed restrictions on property transactions in nine mouzas in Nadia district, including Kalyani, to facilitate land acquisition for the 2,000-acre greenfield airport.Other aviators agreed that the Kalyani project needed closer scrutiny, flagging the complexity of the airspace north of Kolkata. One of the aviators pointed out that departures from Kolkata and from the proposed Kalyani airport could create converging or conflicting flight paths unless the airspace is substantially redesigned.He also warned that the presence of an Air Force aerodrome in Barrackpore, which limits options for routing civilian aircraft in the area, adds another layer of complexity to the runway alignment problem. According to air traffic controllers, flights taking off from Kalyani cannot turn right as it will breach the restricted airspace over Barrackpore. A left turn is also a challenge because of the new Ishwar Gupta Bridge over the Hooghly.A veteran controller said two airports in such close proximity, with landing strips aligned, could function safely only when a satellite-based navigation network providing autonomous geo-spatial positioning, navigation and timing is rolled out.
