U.S. airlines increased their fuel efficiency on domestic
flights by 3% between 2016 and 2018, according to a study by the nonprofit
International Council on Clean Transportation (ICCT). However, emissions during that period
still grew by 7% due to the industry's 10% growth.
Leading the way in efficiency was Frontier, which benefits
from a young fleet, dense aircraft configurations and load factors slightly
above the industry average. Frontier's point-to-point business model is also
more fuel-efficient than the hub-and-spoke networks of legacy carriers Delta,
American and United, on which large number of passengers at least two flights
to reach their destination, the study says.
Fellow ultralow-cost carriers Spirit and Sun Country were
second and forth on the ICCT list, while Southwest, which doesn't offer a space-consuming
first-class cabin, was third. Alaska, United, Allegiant, Delta, American,
Hawaiian and JetBlue rounded out the ranking.
The findings come as the U.S. prepares to enter an
international agreement in 2021 that aims to cap airline emissions at 2020
levels. The agreement, known as the Carbon Offset and Reduction Scheme for International
Aviation, or CORSIA, will require airlines to purchase carbon-offset credits
for emissions that go above the 2020 level, but it applies only to
Nevertheless, authors of the ICCT report said that the
findings "raise questions about how the U.S. aviation industry can meet
its goal of carbon-neutral growth from 2020 without further policy
In a statement, Carter Yang, spokesman for trade group
Airlines for America, called the U.S. airline industry, "a green economic
"The truth is that the airline industry is helping to
lead the fight against climate change with a myriad of measures, including
developing sustainable alternative jet fuels and investing in more
fuel-efficient aircraft," Yang wrote in an email. "In fact, U.S.
airlines increased our overall fuel efficiency by 130% between 1978 and 2018,
saving nearly 5 billion metric tons of CO2 emissions."