Ryanair will tomorrow close a poll that asks what should be the airline's next 'tax', to add to its catalogue of charges such as wheelchair use and payment by debit card.

It's usually easy to ignore the airline's naked thirst for publicity. But the poll results to date are irresistible.

Of 45,000 votes cast so far, nearly half are in favour of charging excess fees for overweight passengers. (The next highest rated suggestion is to charge £3 to smoke in a converted loo. Interesting...).

Ryanair's chief spin doctor, Stephen McNamara, says he is "a little surprised" at the voting so far. But is he really?

The idea of a 'fat tax' has long been an aviation taboo. Yet as the business model of charging for 'extras' - bulkhead seats, checked-in bags, meals and drinks - is now so ingrained, charging passengers by weight is rising back up the agenda.

With Ryanair positioning itself to say that passengers are demanding this charge, the airline could be the first in the UK to act.

There is already precedent in America.

Yesterday, United Airlines became the latest to introduce the charge. "Passengers too large to fit comfortably in a coach seat may be required to buy a second ticket or upgrade to business class, where seats are larger - if United's flight attendants can't find two open seats for them," reports the Los Angeles Times.

The report says that United received more than 700 complaints last year from passengers "who did not have a comfortable flight because the person next to them." The policy brings United in line with the other five biggest US carriers who have already introduced similair charges.

It is a very sensitive subject, not least because of pressure on loss-making airlines to pack in passengers and cut down on fuel bills.

In a Tweet to Timesonline Travel, correspondent elkhorninn said: "I'm 4'10 & 120lbs & I seriously couldn't fit into United's seat; when the guy in front leaned back I got stabbed in the gut."

Given the Ryanair poll results, we decided to run a straw poll of our own - which also shows an appetite for charging. In response to the question "Should overweight passengers be made to pay more on airlines?" - 500 had voted by mid-afternoon, and 63 per cent are in favour.

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