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Thousands of homes in rural areas will be blighted by aircraft noise under the biggest reorganisation of flight paths, which is intended to cope with the rapid growth in air travel and will be announced today.

National Air Traffic Services (Nats), which manages Britain’s airspace, is planning to redirect aircraft over sparsely populated countryside to reduce the impact on urban areas.

The reorganisation affects much of Greater London and the northern Home Counties — an area with 12.5 million residents.

Four new holding stacks, in which aircraft circle while waiting for a landing slot, will be created to serve Stansted, Luton and London City airports.

Under the plan, flights departing from Luton will pass directly over the Chilterns Area of Outstanding Natural Beauty, bringing aircraft noise to dozens of previously tranquil villages. But several towns at present blighted by noise, including Hatfield, Hitchin, Princes Risborough, Southend, Sudbury and Royston, may have fewer aircraft passing over them at low levels.

The main losers will be villages in Essex east of Saffron Walden, south and west of Bishop’s Stortford, along the Blackwater estuary and villages in Hertfordshire north of Berkhamsted, north of St Albans and south of Luton.

Part of Stevenage will also experience more low-flying aircraft taking off from Luton.

Nats was unable to say how many people would be newly affected by aircraft noise. A spokesman said: “We will work it out but we cannot tell you the answer at the moment.”

People can check whether their property is affected by the changes by entering their postcode on a website: nats.co.uk/TCNconsultation.

The changes, which will be subject to a 13-week public consultation starting today, are intended to come into force in stages from March next year after approval by the Civil Aviation Authority.

They are intended partly to remove bottlenecks in the air traffic system, which has been in place for 30 years and was designed to cope with a fraction of today's flights. The number of take-offs and landings at British airports increased from 701,000 in 1975 to 2.4 million in 2006. The changes are also designed to cope with growth in air travel, which the Government is planning to allow to double by 2030.

Nats claims that 20 per cent fewer people will be affected by noise from departing aircraft flying below 4,000ft. But a table buried in the 400-page consultation document reveals that the number of people affected by 57 decibels, which the Government considers to cause significant disturbance, will more than double near Luton and will increase by 11 per cent near London City and 9 per cent near Stansted.

A reduction in the population affected at Heathrow is allowing Nats to argue that there will be only a slight increase in the overall number exposed to 57 decibels.

Nats is refusing to consider any representations objecting to the proposed growth in air travel. It claims that growth is outside its direct control and that its licence requires it “to respond to demand for airspace from aircraft operators”.

The worst bottleneck, which will be removed by the changes, is over Brookmans Park in Hertfordshire, where departure routes from Heathrow, Luton, London City and Northolt converge.

Nats estimates that the changes will reduce delays to airline passengers by four million person-hours between 2009 and 2014. However, when averaged out over all the people flying in those five years, it equates to 22.5 seconds saved per person.

The document says that Nats has been forced to reach a compromise between conflicting interests. “Avoiding both densely populated areas and the surrounding countryside was not possible in airspace that is amongst the busiest in the world. As a result, requests for route changes tended to move routes away from centres of population to less populated countryside.”

Jonathan Astill, head of airspace management for Nats, admitted that the same level of aircraft noise was likely to cause more disturbance in the countryside than in towns because there was more background noise in towns.

He said that Nats had observed a government requirement to minimise the number of people affected by noise. It was proposing to lengthen some departure and approach routes to avoid built-up areas but, in doing so, would increase the amount of fuel burnt by aircraft and raise overall carbon dioxide emissions.

The document says: “Some proposed routes are not as fuel/emissions-efficient as they could be, for example where the airspace design proposes longer routes to help reduce flying over populated areas.”

Nats has decided against giving the public the opportunity to debate different options for flight paths. It claims that it has considered all the options and come up with the best compromise, on which it is inviting comment.

The document says that the public would be unable to understand the “complex air traffic control principles” that would need to be applied when considering different options. The changes are designed to cope with growth up to 2014. Further changes will be needed if the Government proceeds with plans to allow new runways at Heathrow and Stansted.

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