SYDNEY, Apr 4: A Samoan airline that says it is the world’s first carrier to charge passengers by their weight rather than per seat defends the plan as the fairest way to fly, in some cases actually ending up cheaper than conventional tickets. Samoa Air, which opened in 2012, asks passengers to declare their personal weight during booking, which is then charged per kilogram at a rate dependent on flight length. The customers will also be weighed at the check-in counter. (agencies)