It’s weird, and I know it’s weird, but I rather love Michael O’Leary. I know, he’s the man who single-handedly gives the lie to the myth of the friendly Irish, but he makes me laugh. Mr O’Leary, boss of Ryanair, has had his knuckles rapped by the Advertising Standards Authority for advertisements campaigning against Gordon Brown’s increase in air passenger duty.

Naturally, he is refusing to stand in the naughty corner. The ASA criticised the Ryanair ads (“The Great Plane Robber”) for saying that a mere 2 per cent of carbon dioxide emissions were attributable to aviation. It said that in the UK the figure was more like 5 per cent. Today the company’s spokesman said that no, the company wasn’t retracting its ad and he cheekily quoted the eco-scary Stern report to prove that Ryanair’s figure was right. Attaboy.

As it happens, all my prejudices are on the other side, but you can’t help cheering someone who is so very prepared to look like a panto eco-villain. “I don’t give a shite if nobody likes me,” he once told an interviewer, which is just as well, because environmentalists just want him to die.

He has declared that he intends that Ryanair shall increase its carbon dioxide emissions. When critics bang on about global warming, he tells them cheerfully to get out of their cars and walk. Like I say, we wouldn’t see eye to eye about most things, but given a choice between a day at the races with Michael O’Leary and that other Irishman bestriding British aviation, the colourless BA chief executive, Willie Walsh, well, it’s no contest.

Trouble is, he’s still wrong, wrong, wrong about aviation and the environment. Let me explain. I’ve never ever been able to understand why we don’t all get more upset about the Chicago Convention. The what? Exactly. The aviation industry enjoys a tax advantage over every other form of transport – cars, trains, trams, you name it – because uniquely it is exempt from fuel tax. That’s because of the Chicago Convention of 1944, which decided that the nascent airline industry should not have to pay fuel tax in order, as it were, to help it to get off the ground. It still enjoys that exemption.

Can anyone justify it? Anyone? But when I bang on about this at dinner parties, eyes glaze over and people start shifting the conversation to livelier ground – property prices, for instance.

So, since I don’t get the chance anywhere else, let me say it here. This is a bizarre anachronism. And it’s not just planes in the air that escape fuel tax – all the vehicles inside an airport are run on tax-free fuel. But no one is even talking about revoking this provision: not the Government, not the EU. Why not? Well, if the aviation industry paid fuel duty, the economics underpinning budget airlines like Ryanair would look very different.

My pin-up, Michael O’Leary, is right on one thing. There is a Great Plane Robbery. But it’s not the one he has in mind.

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