Gatwick has emphasised the road and rail improvements that will leave it ready for a second runway.
The Sussex airport released a document showing that trains would leave for central London every two and a half minutes by 2019, with overall rail capacity from Gatwick doubled from now to 2020.
It added that road and rail upgrades already planned by the government would allow a second runway to be built without any additional surface access expenditure for the taxpayer.
Gatwick, Heathrow and a new inner Thames Estuary airport are competing for permission to provide extra air capacity in the South East.
Hugh Sumner, senior transport advisor for London Gatwick, said: “Gatwick will be road and rail ready for a second runway by 2021 with no additional cost to the taxpayer. The ease at which these improvements can be delivered adds yet more weight to the obvious case for a new runway at Gatwick.
“Gatwick already has the highest proportion of passengers travelling by public transport and these improvements will help encourage even more. We want 60% of our customers to use public transport, comparable with the best globally and better than any UK airport.”