The weight-based pricing is not new to the airline, which launched in June. It has been using the pricing model since November, but in January the U.S. Department of Transportation approved its international route between American Samoa and Samoa.
The airline's chief executive, Chris Langton, said Tuesday that "planes are run by weight and not by seat, and travelers should be educated on this important issue. The plane can only carry a certain amount of weight and that weight needs to be paid. There is no other way."
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Travelers in the region already are weighed before they fly because the planes used between the islands are small, said David Vaeafe, executive director of the American Samoa Visitors Bureau. Samoa Air's fleet includes two nine-seat planes for commercial routes and a three-seater for an air taxi service.
Langton said passengers who need more room will be given one row on the plane to ensure comfort.
The new pricing system would make Samoa Air the first to charge strictly by weight, a change that Vaeafe said is, "in many ways... a fair concept for passengers."
"For example, a 12- or 13-year-old passenger, who is small in size and weight, won't have to pay an adult fare, based on airline fares that anyone 12 years and older does pay the adult fare," he said.
Vaeafe said the pricing system has worked in Samoa but it's not clear whether it will be embraced by travelers in the U.S. territory.
Langton said the airline has received mixed responses from overseas travelers since it began promoting the pricing on its website and Facebook page.
Ana Faapouli, an American Samoa resident who frequently travels to Samoa, said the pricing scheme will likely be profitable for Samoa Air.
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"Samoa Air is smart enough to find ways to benefit from this service as they will be competing against two other airlines," Faapouli said.
Pago Pago-based Inter Island Airways and Polynesian Airlines, which is owned by the Samoa government, also run flights between the country and American Samoa.