Two of the country's biggest unions have joined forces with the Institute of Directors to urge the government to increase airport capacity.
The GMB and Unite unions warned that 140,000 jobs were at risk unless urgent action was taken.
They said that Heathrow was "perfectly positioned" to act as the South-East's hub airport, branding the idea of an island airport in the Thames Estuary a "vanity project".
They said that the UK economy could be losing £8.5 billion a year by 2021 unless something was done to help businesses access world markets.
Len McCluskey, Unite's general secretary, said: "It is madness to think that the UK can muddle on without a top-quality international hub airport.
"Heathrow is perfectly positioned to fulfil that role and deliver all the associated economic advantages. Decisive action to maintain the airport's status is needed now.
"What is certain is that the country does not have the time nor the money to pursue vanity 'island airport' projects.
"Our economy desperately needs an airport infrastructure which is better than the patchwork provision we currently have around the capital."