Campaigners have warned they will be "up in arms" if BAA abuses new emergency measures at Heathrow to introduce more flights.

John Stewart, chairman of Hacan Clearskies, said a Government task force has proposed granting the air operator more flexibility to land planes on both runways to avoid disruption at critical times, such as severe weather and next year's Olympic Games.

Mr Stewart, who campaigns for residents living under Heathrow’s flightpaths, said: "We understand the need for flexibility during emergencies. The key will be the safeguards which are put in place to ensure that BAA does not abuse its new-found freedom.

"If this does turn out to be the thin end of the wedge, then residents will be up in arms."

The south east airports task force, chaired by Aviation Minister Theresa Villiers, published a report this week which argued the airport should be granted more freedom to avoid disruption caused by incidents including severe weather.

It was said this will be trialled in two phases to gather evidence on the benefits and impacts of these emergency measures.

The first phase will run from November 2011 to February 2012, and the second phase from July 2012 to September 2012, to give the airports greater resilience during the London Olympic and Paralympic Games when the UK’s airports will be under more pressure than normal.

But Ms Villiers has warned that during these measures, residents under the flight paths could experience added noise.

She said: "The work carried out so far indicates that the proposals could result in net environmental benefits, for example through reducing stacking and cutting the number of unscheduled flights during the night period.

"However, on the limited occasions where these freedoms would operate, some communities would be likely to experience aircraft noise during current respite periods, hence the need for safeguards to ensure they are deployed only to anticipate, prevent and mitigate disruption and to facilitate recovery."

Measures to reduce noise at the airport include the switching of landing runways at 3pm each day to give residents in neighbouring boroughs half a day’s break from the noise.