For more than three years the Department for Transport (DfT) has been working on the “Project for the Sustainable Development of Heathrow”. There is no similar team working on expanding Stansted.

In seeking to accommodate a doubling in air travel to 470 million passengers a year by 2030, the Government’s tactic has been to overthreaten and underprovide.

In 2002 it suggested that the South East would need up to three new runways. By December 2003 this had been whittled down to two.

Privately, senior DfT officials say that they would consider it a triumph if just one is was eventually built, as long as it was at Heathrow. By stating in 2003 that Stansted would be the first to gain a new runway, the Government triggered a vociferous and well organised local opposition campaign. The antiHeathrow movement went into abeyance, lulled into believing that it had earned a lengthy reprieve.

But the civil servants have been quietly selecting evidence to support the expansion of Heathrow. BAA, which owns both airports, has devoted thousands of hours to helping the DfT team, feeding it information and suggesting how to polish up the arguments.

BAA has publicly adhered to the government line that Stansted should be expanded first, but it knows the business case is at best marginal. By contrast, any investment in Heathrow is bound to reap rich rewards. Its two runways are operating at 98.5 per cent capacity; Stansted’s single runway can take 40 per cent more flights.

All the big British airlines are arguing for Heathrow’s expansion. Stansted has no such backers.

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