Aviation experts warn proposed Kalyani airport's flight paths conflict with Kolkata airport runway alignment

Aviation experts and retired pilots have raised safety concerns about a proposed greenfield airport in Kalyani, West Bengal, warning that its location falls on the extended centre line of Kolkata airport's primary runway, creating collision risks if both airports operate simultaneously.

Retired senior flight captain Sumanta Roy Chowdhury, who formally flagged the issue with the civil aviation ministry and the Directorate General of Civil Aviation (DGCA), said aircraft taking off from Kalyani could come within 1,000 ft of flights descending into Kolkata, continuously triggering collision-avoidance alarms. He said flights approaching Kolkata descend at roughly 1,500-2,000 ft per minute over Kalyani, while a departing Kalyani aircraft would climb at about 1,000 ft per minute, compressing vertical separation. Other aviators echoed the concern, saying departures from Kolkata and Kalyani could generate converging flight paths unless the surrounding airspace is redesigned. Air traffic controllers noted that aircraft taking off from Kalyani cannot turn right without breaching restricted airspace around the Air Force aerodrome at Barrackpore, while a left turn is constrained by the newly built Ishwar Gupta Bridge over the Hooghly.

The proposed 2,000-acre Kalyani airport was announced in the West Bengal state budget for 2026 to relieve capacity constraints at Kolkata airport, reduce congestion and improve regional air connectivity. Chief Secretary Manoj Pant described the project in a June communication to the land and land reforms department as being planned along the lines of Noida International Airport at Jewar and Navi Mumbai International Airport, citing the absence of expansion scope at Kolkata airport. The registration department subsequently imposed restrictions on property transactions in nine mouzas in Nadia district. Roy Chowdhury noted he had previously joined opposition to a flight school in Kanchrapara approximately 30 years ago on the same airspace-conflict grounds.

Conflicts between a new airport site and an existing runway's protected approach and departure paths are a recurring constraint in dense, multi-aerodrome regions, where military aerodromes and urban infrastructure further narrow the usable airspace. Kolkata's case adds both: a restricted zone around the Barrackpore Air Force aerodrome and a bridge over the Hooghly that limits turn options for departing traffic, on top of the vertical-separation problem raised against the existing runway centre line.

In practice, siting a greenfield airport near a busy hub requires airspace designers to model simultaneous arrival and departure procedures before land is committed, not after, since retrofitting flight paths around fixed obstacles like a bridge or a military zone is far harder than designing around them from the outset. Whether Kalyani can proceed as planned will depend on how the DGCA and civil aviation ministry respond to Roy Chowdhury's formal submission and whether a redesigned airspace structure can reconcile Kolkata's existing runway alignment with Kalyani's planned operations.