Beam me up from Heathrow, Scotty Airline executives do not seem over-impressed by David Cameron's hints at a U-turn over a third runway at London's Heathrow airport. "I don't think it will ever be built," a senior industry figure gloomily tells Notebook. I am very pessimistic about this. Even if the Conservatives come out in favour, Labour would oppose it. It was approved [by a Labour government] in 2009 and then cancelled in 2010. What we need is a cross-party consensus lasting more than a parliament. Brian Groom Last month the prime minister left open the possibility that the Tories might expand Heathrow after the 2015 election. The coalition deal with the Liberal Democrats excludes this, but Mr Cameron has belatedly acknowledged the need to develop London's air links with emerging markets. Justine Greening, transport secretary - a fierce critic of Heathrow expansion - is to publish a delayed "call for evidence" on how to preserve the UK's position as a leading aviation hub. She says Britain will need a four-runway hub airport in the long term but doubts Heathrow could be the location. The £50bn needed to build a new airport on the Isle of Grain or on a man-made island as advocated by Boris Johnson, mayor of London, and by the architect Sir Norman Foster, seems unlikely to be available and it would not be ready before 2028 at the earliest. Mr Johnson suggested a second runway at Stansted. My informant thinks the most likely outcome will be a second runway at Gatwick after the bar on building one is lifted in 2019 - with completion perhaps around 2025. But that would leave London with a divided hub. "I am not sure whether Britain really wants to be in the top tier of competitive nations," laments the executive. It seems content with having once been there. Given the time all this is taking, perhaps the science of teleporting will resolve the issue before another runway is built. Aliens attack Barack Obama would be better than Mitt Romney at handling an invasion by aliens from outer space, according to 64 per cent of Americans in a poll by National Geographic Channel. But how would Britain's leaders fare? Most, Notebook suspects, would take the unsuccessful conciliatory approach adopted by Jack Nicholson's President Jimmy Dale in Tim Burton's 1996 B-movie pastiche Mars Attacks! He refuses to use nuclear weapons even after Martians have massacred the US Congress, and is killed by a robot that crawls up his body when he shakes the ambassador's hand. Winston Churchill, one imagines, would have invited the Martians to share a brandy and cigar rather than attempt to fight them on the beaches. Ted Heath would have wanted to know their attitude towards European integration. Harold Wilson or Jim Callaghan would have invited them to sign a social contract and ballot their invasion force on membership of the Transport and General Workers" Union. John Major would have taken them to a Test match at Lord's while privately denouncing them as "bastards." Margaret Thatcher might have attempted the "not for turning" routine and plonked her handbag down purposefully on the negotiating table. Mistakenly thinking they were as spineless as the Tory wets, she would have met a grisly end. Tony Blair would have inquired whether they were interested in creating an interplanetary federation over which he could preside. Gordon Brown would have invited them to join him in creating an Intergalactic Monetary Fund and saving the universe through fiscal stimulus. And David Cameron? He would invite them for a pint of Sharp's Doom Bar and a game of tennis and promise them a referendum on joining Earth at an unspecified point in future. Quids out RIP The Word, the magazine created nine years ago for 50-Quid Bloke, "the guy we've all seen in Borders or HMV on a Friday afternoon, possibly after a drink or two, tie slightly undone, buying two CDs, a DVD and maybe a book - 50 quid's worth - and frantically computing how he's going to convince his partner that this is a really, really worthwhile investment." And what now of 50-Quid Bloke himself? Lost somewhere in cyberspace, strapped for disposable income.