While some airlines have done experiments in running planes on biofuels, air travel normally requires an enormous output of carbon-emitting jet fuel. Various factors, like plane models, total load, and chosen route can effect one trip's fuel efficiency, but which airlines consistently manage to use the least fuel in their operations? This is a look at the most fuel efficient airlines, based on the amount of fuel used for each seat-mile (how much fuel moves one passenger one mile).
SOURCE The Wall Street Journal
A collaboration between GOOD and Amanda Buck.