What a second runway at Gatwick would mean for flyers

Transport secretary Heidi Alexander has given the go-ahead for a second runway at London Gatwick airport. The controversial £2.2bn project will see the Sussex almost double its capacity - which proponents say will increase choice and resilience and help cut fares.

- Simon Calder, The Independent

Heidi Alexander

But the minister's announcement has been condemned by environmentalists, who say they will launch a legal challenge. The Independent looks at the key questions and answers for Gatwick and the Government.

What is the problem that the runway is designed to solve?London is the world capital of aviation. More people fly in and out of the city's airports than anywhere on earth. But due to extreme capacity constraints at both of the biggest airports, Heathrow and Gatwick, the current arrangements are dysfunctional. Heathrow is the busiest two-runway airport in the world, and Gatwick has more flights using its single runway than any other airport. There is simply no slack in the system.

While the government has given its backing to an additional runway at Heathrow, that project remains mired in controversy - both because of the environmental impact and the huge cost, which will total almost £50bn once associated work is taken into account. Gatwick, about 35 miles around the M25, has adopted an entirely different approach. Basically: "here's one we prepared earlier".