Former transport secretary Justine Greening has claimed an expanded Heathrow would increase the risk of an air catastrophe over London.
The international development secretary claimed it would be more likely that an aircraft would fall from the skies into a highly populated area of west London — either due to human error or a terrorist attack — if there were more flights.
She predicted that Heathrow could end up with six runways if it was allowed to develop into UK’s single aviation hub.
The MP for Putney claimed that despite Heathrow’s good safety record, human error meant that the risk of a crash could never be reduced to zero, the London Evening Standard reported.
She added: “In addition to that, aviation clearly faces other risks, not least terrorism.
“Even one accident could be catastrophic not only on loss of life but also London infrastructure.
“The higher the absolute number of aircraft movements, the higher the danger that even an ‘extremely low probability’ event may occur. We cannot beat the odds forever.”
Greening warned that allowing expansion at Heathrow would be “one of the biggest planning and transport strategy mistakes of this century, irreversibly blighting Londoners’ quality of life”.
She added: “If Heathrow continues as a future UK hub and needs significant numbers of new runways, eg six … we would potentially rapidly reach a point where the extent of London flown over becomes practically the entire population.”
She urged Airports Commission chairman Sir Howard Davies to rule out supporting a third runway at Heathrow, insisting that it would be “politically undeliverable” as it would need consensus between parties over several parliaments.
But Labour peer Lord Soley, a prominent campaigner for a bigger Heathrow, condemned Greening’s warning as “scaremongering of the worst type,” the newspaper reported.
He argued that trains already pass through many constituencies in London at 100mph, with homes nearby.
He said: “The message to her is ‘there is not an absolutely safe form of fast transport but aviation is safer than all the others’.”
Sir John Randall, MP for Uxbridge and South Ruislip, warned that lives could be endangered by taking the “unsafe gamble” of more flights at Heathrow before the “full, hidden and long-term” health effects from noise are properly known.
The former Tory deputy chief whip said a third runway risked “endangering the quality of life, and possibly the life, of affected residents”.
A Heathrow spokesman said: “Air travel is one of the safest forms of transport and Heathrow is recognised as one of the safest airports in the world.”