The embattled transport secretary, Chris Grayling, was fighting for his political life this weekend as Tory council bosses accused him of a “giant con” over Heathrow’s third runway.

Jet noise maps, published by the airport and analysed by local authorities, reveal the potential noise impact, once the runway is complete, across huge swathes of London and southern England that were not previously overflown.

In some areas of the capital and the home counties that have not previously suffered jet noise, the noise maps reveal that up to 47 flights an hour might pass overhead.

In October 2016 Grayling promised parliament that “fewer people will be affected by noise than is the case today” after the third runway was built. He made the pledge even though the expansion would mean more than 250,000 extra flights a year, equivalent to bolting an additional airport almost the size of Gatwick onto the existing site.

A three-runway Heathrow will accommodate up to 740,000 flights a year, more than half as many again as the current 475,000. Grayling believes aircraft will be quieter and so affect fewer residents.

This weekend council bosses, including the leaders of Wandsworth and Windsor and Maidenhead, said the documents demolished Grayling’s claim. Court proceedings on the case will start next week.

Ravi Govindia, the Tory leader of Wandsworth council, said the public had been the victims of a “giant con”.

He said: “It beggars belief that people will believe Chris Grayling in his assertion that no more people will be affected. When you see the maps, virtually the whole of London and a large part of the southeast will be affected by additional flights.

“There are people in the south of this borough who have often said aircraft noise is not their problem. Well, it’s coming to their doorstep now.”

The new row comes after Grayling has been accused of incompetence and mismanagement over the awarding of a ferry contract to a firm with no ships. The government agreed to pay £33m in compensation to Eurotunnel last week over the “secretive”contract process.

The new maps, released as part of a Heathrow consultation on airspace and future operations that began in January, identify “design envelopes” where planes may pass overhead at sound levels of 65 decibels and higher after the completion of the third runway by 2025.

Council experts who have analysed the documents say the areas at risk of additional noise include large areas of London, such as parts of Westminster, Kensington, Chiswick, Balham, Fulham, Tooting and Hammersmith. Towns and commuter-belt communities in the home counties, including Chertsey and Epsom in Surrey; Maidenhead, Slough and Ascot in Berkshire; and High Wycombe in Buckinghamshire, are also caught up.

Five councils — Windsor and Maidenhead, Richmond, Wandsworth, Hillingdon and Hammersmith and Fulham — are seeking a judicial review of the Heathrow expansion in a hearing due to start next week.

Simon Dudley, Tory leader of Windsor and Maidenhead council, said he believed the noise maps now available had been previously withheld by Grayling’s officials “with the intention or deceiving and misleading public”.

The battle over Heathrow has been one of the most controversial planning battles in recent decades. In May 2010 the Conservative-Liberal Democrat coalition scrapped plans for a third runway, but two years later the proposal was back on the table as an independent commission was set up to examine airport expansion. The Heathrow proposal was backed by ministers in 2016, and MPs voted in favour of the plans in June last year.

The Department for Transport said: “We absolutely refute these claims and are confident that fewer people will be affected by noise pollution under the new flight paths planned. The airports national policy statement agreed by the government makes it clear that we expect noise mitigation measures to limit, and where possible reduce, the impact of aircraft noise.”  [This is the department for which Grayling has responsibility. It is still putting out this nonsense.  The claim can only be justified by using extraordinarily distorted definitions of noise, far from the reality any ordinaryperson would understand. Distorting noise metrics for the DfT’s and Heathrow dishonest convenience. AW comment]. 

A Heathrow spokesman said, “Parliament voted overwhelmingly to back Heathrow expansion last year, and we continue to engage with local people as we develop our plans.”  [They voted for it partly because most MPs do not have constituencies affected by Heathrow; – they did not really care;  the Tories were whipped into voting in favour; some powerful unions lobbied very hard to get Labour MPs to vote for it, with unrealistic hopes of future jobs; and Grayling misled Parliament on many issues – this noise one as a case in point. He also ignored the climate implications, and the Paris Agreement. As well as most air pollution, more than 2km from the airport.  All shocking abuse of the role of Parliament.  AW comment].