Most economy seats on planes are about 17ins (43 cms) wide - and becoming a bit of a squeeze for some in the world's wealthier countries as they pile on the pounds.

Airbus, with its wider planes, builds in seats with an extra inch of width and is now calling on other manufacturers to do the same.

But as Greg McKenzie discovers smaller seats enable airlines to get more passengers on their planes and make more money - so could larger seats carry a larger price tag?