Gatwick Airport has announced its preferred location for a second runway.
The airport has revealed details of its final submission to the Davies Commission, which is looking at raising airport capacity.
Chief executive Stewart Wingate said the airport wanted a second runway to be positioned south of the existing airport.
He said there was a "robust and compelling case" for going ahead with the plans.
Mr Wingate said building an extra runway at Gatwick could be privately financed and was "the best and most deliverable solution".
Several options have been put forward for increasing aviation capacity including the expansion of Gatwick in West Sussex, the expansion of Heathrow, the building of a new hub airport in the Thames Estuary and greater use of existing regional airports across the South East.
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Mr Wingate said expansion at Gatwick would cost between £5bn and £9bn and the second runway could be open by 2025.
He said the plans had the support of business groups including the Gatwick Diamond Initiative and Sussex Enterprise and local authorities including West Sussex County Council and Kent County Council.
He added: "A two-runway Gatwick, as part of a constellation of three major airports surrounding London, will also provide flexibility in an industry where the only constant is change."
He said other world cities, including New York, Tokyo, Paris and Moscow, also operated a multi-airport or "constellation" system and could handle greater numbers of passengers than cities relying on a single hub.
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The airport has set out three options for configuring and operating a southern parallel runway.
Gatwick said the first option would have capacity of 60-66 million passengers a year by 2050, compared with option two which could take up to 82 million and the third option allowing up to 87 million a year.
Louise Goldsmith, leader of West Sussex County Council, said the authority had supported the Gatwick expansion because of the "huge potential economic benefits" for the county.
She added: "We want to work with Gatwick, residents and partners to ensure that any development will take into account the environmental concerns that people rightly have, and include all of the essential infrastructure that a development of this scale would require."
But chairman of the Gatwick Area Conservation Campaign Brendon Sewill said: "When people begin to realise what is likely to hit them, there will be a tidal wave of public resistance."
He said there was no need for any new runway in the South East, Stansted Airport was less than half full, new larger aircraft were coming into use and there was sufficient airport capacity to last until 2050.
Green Party MEP Keith Taylor said Gatwick bosses were "hell-bent" on bringing more flights into the UK's airspace and "more than happy to gloss over the grave environmental and health implications of airport expansion".
Earlier, Mr Wingate said studies had shown the numbers of people impacted by noise from a two-runway Gatwick would range from 3,300 to 11,800, and the airport would be able to keep within European and national air quality standard limits.