Does my bum look big in this Boeing?

Sitting comfortably?

Ryan Dilley BBC News Online

An American airline is charging extra for those passengers who cannot fit into a single seat, but is it just the obese who are feeling the squeeze?

Should you approach a check-in desk of the budget US carrier Southwest Airlines, try to look narrow. Those deemed too wide for their seat are now to be charged for a neighbouring one as well.

"I'll breathe in, I promise"

Now wedged in a public relations fiasco, Southwest says it is merely making explicit a long-standing policy for passengers who encroach on the space of those seated around them.

It is tempting to see the issue as a storm in a super-sized cola cup (with a burger and large fries please), but obese Americans are not the only ones being squeezed by the airlines.

The average width of economy seats on the ten most popular international airlines is less than 18 inches, though those on SAS were a spacious 21 inches.

No pain in the SAS

Seats as narrow as 15 inches were found by a recent Civil Aviation Authority (CAA) study looking at the safety implications of UK aeroplane layouts.

While Britons are not as burly as their American cousins, more than a third of British women and a fifth of men would not fit their hips into such a small seat.

More than 5% of British women would not even be able to squeeze between the armrests of an average economy seat.

	How wide is your economy seat? Lufthansa 17 inches British Airways 17.25 inches Swissair 17.3 inches United Airlines 18 inches SAS 21 inches How wide are your hips? 50% of British women 13.9 inches plus 36% of British women 15 inches plus 5% of British women 19 inches plus 1% of British women 21 inches plus Sources: IATA, System Concepts

Seats on UK trains, coaches and buses must be at least 17 inches across according to government regulations, however no similar stipulation applies to the UK's airliners.

And it's not only comfort at stake. Those crammed into their seats before take off may find it difficult to escape in an emergency, according to British ergonomists evaluating the current rules.

A person struggling to leave a narrow seat may also hinder the evacuation of other passengers - a problem that not necessarily avoided by forcing large travellers to buy two seats.

The CAA's Airworthiness Notice 64 (AN64), which sets the standard for seat spacing on UK aircraft, does stipulate a minimum distance of 26 inches between your seat back and the seat in front.

This so-called seat "pitch" - how much legroom a passenger enjoys - has been the focus for the recent debate over deep vein thrombosis (DVT). However, seat width has also been suggested as a contributory factor to the potentially fatal blood clotting condition.

Tight squeeze = DVT?

While squeezing yourself into a too-small seat can cause the sort of "tissue compression" that could restrict blood flow and trigger DVT, even slim-hipped passengers may be at risk.

"[A narrow seat] restricts the opportunity for passengers to change posture, not only because of the limited space but also because of the disturbance it may cause the adjacent passenger," says the CAA survey.

"We're going to need a bigger plane"

It goes on to recommend that AN64 set a minimum distance of almost 20 inches between the armrests. The ideal width should be a spacious 23 inches, leaving only 1% of passengers still feeling the pinch.

Tom Stewart, managing director of ergonomics consultants System Concepts, says that while obesity is a growing problem, healthy Britons are becoming larger too.

"People are generally bigger than they were. A poor diet used to mean people didn't reach their full potential size. Improved nutrition has changed that."

Turn the other cheek

Mr Stewart says the size of airline seats is a "classic ergonomic trade-off". To accommodate the minority of passengers who are too large for existing seat would cost the airlines and possibly push up fares for all travellers.

"Things like office furniture usually suit everybody except the very small or very large. For these people special arrangements can be made, such as putting their desk up on blocks. With an aircraft seat there's very little you can do make such adjustments," says Mr Stewart.

"And your seat's next to the PM, Mr Prescott"

So what about booking a ticket and hoping you can spread across an empty seat when you board your flight? Fat chance.

Research by aircraft maker Boeing found that if economy seats in its 777 airliner were arranged with three by each window and three in the centre, the flight would have to be two-thirds full before passengers had to seated beside one another.

While Boeing recommends this 3-3-3 configurations, many airlines operate a 2-5-2 system almost guaranteeing you'll have a neighbour if half the seats have been sold.

Recent changes in the airline industry have seen spare capacity cut to the bone, making half or even two-thirds full jets something of a rarity. According to Dr George Williams from Cranfield University's College of Aeronautics, most airliners now fly at 75% capacity. The cheek!

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Do you feel the squeeze thanks to narrow airline seats? Send us your comments using the form below.

Your comments:

Apparently most of your correspondents don't appreciate that the size of the fuselage is fixed, i.e. an airline would have to take out a whole column of seats to make them wider. I don't see this happening in the immediate future.
David, US

Returning from the US on KLM my wife could not recline her seat without amputating the knees of the Dutch guy behind, who statistically belongs to the world's tallest nation. But KLM can't increase their seat pitch because of competition! On KLM in Europe try to get seat in the first 14 rows. These seats are all "business class size", even for tourist class fares.
Graham Chambers, Luxembourg

I am an average 5ft 10ins and even in the new BA Club Class beds, if you are an inch taller than me you would have to bend your knees up to fit onto the bed. They can never get it right even if you pay a premium!
Simon, England

I can fit comfortably in an economy class airline seat. But I did have the discomfort of flying to Australia sat next to a woman who did not. Every time she moved, the armrest would pop up and she would encroach even further onto my seat. I'd like to see seating space increased as I don't savour the thought of another 24 hour flight with a stranger on my lap.
Janine, England

As a larger gentleman I feel as if I need to be injection moulded into most airline seats. The trauma of my knees bashing against the seat in front drives me mad. This usually takes place in a business class seat located in row 35, next to an adenoidal couple, a yoga practitioner and a child whose voice box should be attached to Beachy Head lighthouse to warn passing freighters of impending doom.
Mike, England

Time and time again I have been denied use of the armrest and even on occasion my tray table because the large person next to me is infringing on the space that I paid for. There should be a premium to pay if you are too big to fit into the seat, and travellers sitting next to a large person should be able to move or get a discount.
Lee Barden, US

Being 6 foot 8 inches I find most airline seats unbearable and now on most package holidays you have to pay extra to reserve front row seats or emergency exits.
James West, England

Although I'm not fat (admittedly I've got a bit of a beer gut), I'm naturally large built (6' 5'' and in proportion width-wise) and find airline seats ludicrously small, so much so it is not physically possible for me to sit in a seat and not encroach upon my neighbour's space. There is physically nothing I can do about this, my genes have determined that I am one of the larger members of our species and for this I have to suffer additional economy class discomfort. I have debated space allocation with numerous airlines, and although I am always greeted with a sympathetic line, there is never anything that can be done to rectify the fact that their seat size allocations are neither well-thought through nor contemporary.
Matt Morris, England

Being a thin person, is my ticket cost reduced by 50%?
Jams Naylor, Holland

I'm not wide, but I am 6'3", and basically airlines and companies have to accept that having people like me squeezed into a space a hamster would find too small is unpleasant at best. I'd like to see more sensible minimum sizes for seating in planes enforced, even if it means cost goes up a bit.
Dave, England

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