U.S. domestic airlines show no overall improvement in fuel efficiency in 2013

Spirit, Frontier tie Alaska for most fuel-efficient U.S. domestic airline in 2013

American slips, with no overall improvement for U.S. airlines

Alaska, Spirit, and Frontier Airlines tied as the most fuel-efficient U.S. domestic carrier in 2013, according to a study released today by the International Council on Clean Transportation (ICCT). Alaska and Spirit have consistently led the performance ranking since ICCT’s original baseline analysis of 2010 data. Frontier leapfrogged Southwest Airlines thanks to a large (+10%) one-year improvement. Last year the worst carrier, American Airlines, burned an estimated 27% more fuel than the three most efficient airlines to provide an equivalent level of transport service.

Fuel efficiency ranking on U.S. domestic operations, 2010–2013

* Tie †Merged‡ Merged

The study found no net improvement in U.S. domestic airline fuel efficiency in 2013, consistent with a trend of falling improvements after 2010. The top carriers made significant efficiency gains, but these were offset by stagnation or even backsliding from larger legacy carriers, notably American, whose fuel efficiency fell by 1.5% in 2013. The slowdown raises questions about the industry’s ability as a whole to meet its goal for carbon-neutral growth from 2020, particularly if fuel prices remain steady or even fall, further reducing the incentive for improvements.

Annual changes in fuel efficiency for U.S. domestic operations, 1990 to 2013

Multiple factors help explain the industry-wide slowdown in improvement. Load factors on domestic flights, which increased from 60% in 1990 to 82% in 2010, have flattened out in recent years and are not currently contributing to overall efficiency gains. Deliveries of new aircraft to U.S. carriers have fallen sharply – more than 60% off their peak in the last decade – so that today only one in seven new planes are delivered domestically. Fewer deliveries of new aircraft have translated to an aging U.S. fleet, which reached almost 12 years on average last year. To compound these trends, relatively few new, more efficient aircraft types have been brought to market over the past 15 years.

“Smaller carriers like Alaska, Spirit, and Frontier continue to improve their fuel efficiency, but larger carriers like American have not been pitching in in recent years,” said Dan Rutherford, the ICCT’s program director for aviation and one of the paper’s coauthors. “The data suggest that efficiency improvements for the aviation sector can no longer be taken for granted, so policymakers concerned about energy security and climate change should take notice.”

Airlines’ in-use fuel efficiency is directly related to aviation’s climate impact. In the U.S., aviation accounted for about 10% of energy-related carbon dioxide emissions from the transportation sector (3% of the U.S. total) in 2013. If counted as a country, globally the aviation sector would have ranked 7th in terms of carbon dioxide (CO₂) emissions, just after Germany and well above Korea, in 2011. Aviation CO₂ emissions are projected to triple by 2050 under business-as-usual scenarios, as more people and goods move by air, unless effective policies are developed to constrain emissions growth.

Download the study here [.pdf] or visit http://theicct.org/us-domestic-airline-fuel-efficiency-ranking-2013