Airports Commission's shortlisted options

In a charm offensive last weekend Heathrow announced it would set aside £550m for the purchase of homes on the proposed site and sound insulation for those nearby. But opponents have warned expansion of the airport would be , adding hundreds of thousands of homes to the 700,000 which are already under the flight path.

Expanding Heathrow would allow it to operate as Britain’s “Hub” airport, offering a huge range of connecting flights for international passengers. However, opponents point out that the biggest area of growth in air travel recently has been in the low-cost sector, which operates principally from Gatwick and Stansted.

Heathrow Hub

A second proposal drawn up by Capt William “Jock” Lowe, a former Concorde pilot, and not formally submitted by Heathrow Airport, would extend the existing northern runway to at least 6,000m.

This would allow the runway to effectively operate as two separate strips for both take offs and landings. The plan’s backers insist it would be cheaper and cause less noise pollution, but critics say it would cause huge disruption to the M25.

Gatwick

Gatwick Airport, the world’s busiest single-runway airport has proposed building a second 3,000m runway to the south of the current one, with the two strips operating independently of one another.

Gatwick argues that its expansion would be significantly cheaper than Heathrow, costing up to £9bn, and could be completed by 2025. It would cause less noise pollution than either option at Heathrow.

However, options for flight transfers at Gatwick are extremely limited and its bid depends on splitting capacity between two major airports. If the Airports Commission decides Britain needs a “Hub” airport to compete with international rivals such as Amsterdam Schiphol and Paris Charles de Gaulle, it will effectively rule out Gatwick’s bid.

^{An artist's impression of the Thames Estuary airport (PA)}

Isle of Grain

A radical proposal backed by the Mayor of London would see Heathrow closed and a new four-runway hub airport opened on the Isle of Grain in the Thames Estuary. The Airports commission has not shortlisted the proposal, but has kept it on the table while more detailed plans are drawn up.

The plan would likely cost at least £80bn and concerns have been raised about the potential threat to nearby wildlife, the possibility of planes being hit by bird strikes, and the time it would take to build as well as the economic impact on Heathrow. Sir Howard Davies was forced to deny in December the option had only been kept in play due to last-minute political lobbying from Mr Johnson.

Backers say it would likely be privately funded and would create thousands of jobs in the region, as well as allowing London to compete with hub airports in Europe. It would involve the creation of a new town on the Heathrow site, and would free hundreds of thousands of homes from noise pollution.

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