Kent County Council has withdrawn its support for a second runway at Gatwick due to changes in flight paths.
Council leader Paul Carter told the BBC that the new flight paths had made life intolerable for people living in the Bidborough, Chiddingstone and Speldhurst areas.
The council previously support the second runway in its report, Bold Steps for Aviation, published in May 2012.
The council’s new policy is expected to be approved by its cabinet on December 5 and submitted to the Airports Commission as part of its three month consultation.
Five MPs from Kent, Surrey and Sussex also expressed their concerns about the new flight paths and the second runway, at a meeting in Crawley on Saturday organised by Gatwick Area Conservation Campaign, the BBC reported.
Carter said: “What has changed big time is that the National Air Traffic Control have started to implement changes in flight paths.
“This has brought to our attention the concentration in flight paths but also that the number of night flights at Gatwick is about three and a half times the number at Heathrow, which is a massive issue.”
Gatwick’s airports commission director, Alastair McDermid, said flight path changes had reduced the number of people who were affected by aircraft noise but those under the new routes did have more noise.
“There will be no further changes while we look at this and we try to learn would be the best way to implement them,” he said.
He said thousands of households affected by noise from a second runway would get £1,000 a year compensation and insulation grants.
The Airports Commission is considering three options for airport expansion in the south-east – a second runway at Gatwick, a third runway at Heathrow, or an extension to one of the existing Heathrow runways.