Men and tall travelers are biggest losers if airlines adopt pay-by-weight airfares

This week Samoa Air, in a move that was mistaken by many for a belated April Fools’ Day prank, became the first airline to charge passengers according to their weight.

Passengers flying on the South Pacific carrier, which largely operates domestic routes, must now pay one Samoan tālā (around 29p) for each kilo that they, combined with their luggage, weigh.

The biggest single cost for all major airlines is jet fuel, the price of which has risen sharply in recent years. Carriers have responded by devising ever more imaginative ways of cutting the weight of their aircraft. Last year Ryanair even reduced the size of its in-flight magazine from A4 to A5, which it claimed would save £400,000 a year. Therefore it is not unreasonable to believe such a policy could now be adopted by other airlines. Should they do so, public backing can be expected. Previous polls conducted by Telegraph Travel have shown that around half of readers would like to see overweight passengers pay more.

But how much would you save if British Airways, for example, chose to go down the same route?

Samoa Air’s calculations are simple: 1kg = 1 Samoan tālā. Therefore the 10-minute hop from Maota, the main airport on the island of Savai’i, to Faleolo International Airport, would cost the average Briton, weighing 12 stone, or just over 76 kilos, and carrying 10 kilos of hand luggage (the smallest amount permitted by ALL airlines – including Ryanair), the equivalent of £24.80.

The same flight would cost heavyweight boxer David Haye (95.5 kilos) £30.45, but fellow pugilist Amir Khan (63 kilos) would pay just £21.05.

An average family of four (according to figures from 2010, the average British male weighs 13st, a female weighs 11st, two children around 5.5st – so total weight is 35 stone, or 262.3 kilos, including luggage) would pay £75.70. But four male travellers (52 stone, or 340.2 kilos with bags) would pay £95.

These calculations work for short flights, such as those operated by Samoa Air. To see how such a policy would affect prices if a major airline adopted it, they need to be scaled up. The average cost of an economy class ticket on BA flight from London to Edinburgh is £41. If the average 76-kilo adult Briton (with 10 kilos of luggage) paid the average price, then they are paying 48 pence per kilo. Copying the rigid Samoa Air formula, David Haye would be expected to fork out £50.65, but Amir Khan would reach Scotland for just £35.05.

As you can see from the table below, the policy would stand to benefit slim and short travellers (obviously), women, families with children, and business travellers without luggage, with greater savings to be had the further you travel. For example, David Haye would pay around £175 more than Amir Khan on a flight to Australia.

Overweight and tall passengers would suffer, as would men in general, as well as leisure and sports travellers carrying lots of luggage.

Note: These calculations are imprecise: we have not found reliable data on the average number of children on flights, for example. However, we hope it will at least give an idea of who would benefit and by how much should such a policy become more widespread. A spokesman for BA said it “would never consider such a policy”.