Alaska Airlines was the most fuel-efficient U.S. carrier for domestic operations in 2011 and 2012, according to a nonprofit organization’s analysis. Allegiant Air and American Airlines were the least fuel-efficient carriers during the survey period, the International Council on Clean Transportation (ICCT) says in a study released on April 30.
The ICCT analysis is based on fuel-consumption data airlines report annually to the U.S. Bureau of Transportation Statistics. Alaska Airlines, a Boeing 737 operator, also ranked first in fuel efficiency in a 2010 benchmark assessment ICCT published last year. Spirit Airlines, which operates an Airbus narrowbody fleet, ranked second all three years. At the opposite end, Allegiant Air and American Airlines each burned 26 percent more fuel than Alaska Airlines to provide an equivalent level of service.
“There’s a tremendous disparity in aircraft fleet age and fuel efficiency between airlines,” said Dan Rutherford, ICCT aviation program director. “Alaska is very efficient in large part because it operates a new Boeing fleet and uses turboprops on regional flights. In contrast, American and Allegiant use old, fuel-intensive McDonnell Douglas aircraft and regional jets extensively.” The average aircraft age in Alaska Airlines’ fleet was seven years in 2012, compared with about 23 years for Allegiant.
Airlines use the same types of aircraft either more or less efficiently. “Spirit is up to 34 percent more efficient on a passenger-mile-per-fuel basis with its Airbus aircraft, in part because of higher seating densities and passenger load factors,” the organization said. “An A320 flight on Spirit may transport 20 to 30 more passengers than one on another carrier.”
Mergers affected airline fuel-efficiency differently, according to the ICCT. Southwest improved in efficiency in both 2011 and 2012 after merging with less efficient AirTran. In contrast, United had a lower fuel-efficiency score in 2012 than would have been expected based on the 2010 performance of United and merger partner Continental.
The overall fuel efficiency of U.S. airlines on domestic operations improved by 2.3 percent from 2010 to 2012, which was less than needed to meet U.S. greenhouse gas (GHG) reduction goals, the ICCT said. Globally, GHG emissions are rising 3 percent to 4 percent annually, and efforts to change the trend are slow-moving, it argued. “A lawsuit brought by environmental groups against the [U.S.] Environmental Protection Agency to force [the agency] to regulate aircraft GHG emissions as it already does for cars and trucks remains in limbo, while the International Civil Aviation Organization is not expected to finalize international measures until at least 2016.”