Gatwick says it can handle 11 million more passengers a year by 2030 without needing a second runway.
The airport's publishing plans for its future later today.
Gatwick currently handles around 34 million passengers a year but says it could handle up to 45 million. One of their aims is to get more people to travel to the Sussex terminals by train.
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Saturday's weather for the east with Philippa
Saturday's weather for the west with Philippa
Memorial events are taking place in tribute to the victims of the Shoreham air crash.