(CBS News) Samoa Airlines made headlines earlier this month when it began charging passengers based on their weight. Critics say it's not fair -- but the plan is paying off for the carrier.
Samoa Air flies routes connecting the Samoan Islands, located more than 2,000 miles southwest of Hawaii. The islands are home to some of the world's biggest people, and now the only airline where passengers weigh in and pay by the pound. Chris Langton, the airline's chief executive officer, developed the idea. He told CBS News, "It has to be a fair system no matter what you're shipping -- whether it's people, whether it's cargo."
One of the biggest costs for an airline is fuel. The more a plane weighs, the more fuel it uses. Large commercial airlines are compensating by charging more for everything, from beverages to baggage, but Langton can't do that because his planes have little cargo space and don't offer drinks.
Langton said, "An airline only has weight to sell. That's it's product. And you're asking people to buy as much weight as they need."
Many Samoa Air passengers are large. The World Health Organization reports that 86 percent of Samoans are overweight due to sedentary lifestyles and high-fat diets.
At check in, passengers step on an airport scale and pay roughly a dollar-per-kilo, or 50 cents per pound, for their bags and body weight. So a 300-pound Samoan man with a 40-pound suitcase would pay almost $200 for a one-way ticket to another island. But that same person on a competitor's airline could pay up to $50 less.
Jason Pritchard, president of J&J World Travel, said, "Larger people might feel cheated in a way. Like, 'Why am I being charged extra because I weigh more'?"
Pritchard, a travel agent on the island of American Samoa, said of customers, "They call and ask us about it, and we tell them it's by weight, and they say, 'OK, thank you," and then they say goodbye."
But people are buying tickets online. And most airlines already ask for each passenger's weight to balance the islands' small planes. Stepping on a scale is routine, although paying for weight is new.
Traveler Tasalao Tele said, "We're from a culture where everything's very open - we all know each other's business, weight."
Some passengers like Tele are embracing the pay-by-weight system. And so is her friend Leilani Curry, who actually paid more for the same flight. But she says it was worth it. Curry said, "Because I'm heavier, they gave me more room."
So far idea has been worth its weight -- in profits -- up 20 percent since pay-by-weight first got off the ground.
Watch Ben Tracy's full report in the video above.