Alaska and Spirit the most fuel-efficient on US domestic operations with overall trend showing modest gain
Wed 7 May 2014 – Alaska Airlines and Spirit Airlines have widened their lead over other carriers as the most fuel-efficient on US domestic operations in both 2011 and 2012, according to an analysis by the US-based International Council on Clean Transportation (ICCT). The two airlines were found to have deployed new, efficient fleets and technologies as well as more efficient operational practices. The two least fuel-efficient airlines, Allegiant Air and American Airlines, both burned 26 per cent more fuel than Alaska to provide an equivalent level of transport service, the same gap ICCT found in a benchmark performance assessment for 2010. Although overall fuel efficiency on domestic airlines improved by 2.3 per cent from 2010 to 2012, this fell short of US government and ICAO international aviation goals, says the independent non-profit environmental research organisation.
The study highlights key factors in airline efficiency performance with technology, unsurprisingly, having a strong impact, although load factors and higher seating densities play an important part.
“There’s a tremendous disparity in aircraft fleet age and fuel efficiency between airlines,” said Dan Rutherford, the ICCT’s Program Director for aviation and one of the study’s co-authors. “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 age of the Alaska fleet was seven years in 2012, compared to about 23 years for Allegiant.
The two most efficient carriers – Alaska and Spirit – had the highest net operating profit margins from 2010 to 2012. However, although fuel accounts for about a third of airline operating costs, and fuel prices remained consistently high during the period studied, the analysis found a poor correlation between efficiency and profitability. The third most profitable airline was found to be the most fuel-inefficient, Allegiant, followed by Delta Air Lines, both of which pursue a strategy of operating older, cheaper aircraft rather than investing in efficiency.
Another example is an airline opting to load more fuel than required because the fuel is cheaper at certain airports and/or to reduce turnaround time at the flight’s next stop. This results in heavier aircraft which in turn causes additional fuel burn. “There can be a trade-off between financial and environmental costs, with some choosing the latter,” said Rutherford.
Airlines also use the same types of aircraft more and less efficiently. Spirit, for example, is up to 34% more efficient on a passenger-mile-per-fuel basis with its Airbus aircraft due in part to higher seating densities and passenger load factors. As well as operating one of the youngest fleets on domestic US routes, an Airbus A320 flight on Spirit may transport 20 to 30 more passengers than one on another carrier and the ICCT points out other efficiency gains by the carrier as a result of lighter on-board furnishings and a reduced baggage load due to its fee structure.
The 2.3% overall fuel efficiency improvement between 2010 and 2012 works out at an annual 1.1% per year, which falls short not just of aviation sector goals but lags well behind other transport modes. The ICCT says in the United States, aviation accounted for around 11% of energy-related CO2 emissions from transportation, or around 4% of the US total. Globally, aviation greenhouse gas emissions are rising 3% to 4% annually, and are expected to quadruple by mid-century if present trends continue, it points out.
The fuel efficiency of US domestic operations improved strongly from 1990 to 2008, averaging 3% per year, due to improvements in new aircraft efficiency and rising load factors, but the ICCT is alarmed at the current slowdown, just as climate pressures are speeding up.
“In recent years, gains from new aircraft in the US have fallen, raising the risk that efficiency improvements will stall completely as the marginal gains of filling every available seat drop off,” said Rutherford. “We first identified the trend of falling improvement for new equipment back in 2009. It’s driven by a lack of new types and by prioritisation of aircraft performance, notably range and speed, over fuel burn improvements. Due to the time lag between new aircraft delivery and penetration into the in-use fleet, this slowdown is now evident at the airline level.”
Rutherford hopes the entry into service of new aircraft types like the 787-8 and new projects such as the A320neo, 737 MAX and the 777X will eventually cause the trend to reverse. However, sufficient regulatory and environmental pressure will also be required at both a US domestic and international level to improve the industry’s environmental performance and limit the growth of aviation emissions, he said.
The report says policymakers, the business community and the travelling public are increasingly demanding better information on airline fuel efficiency to inform their policy, investment and purchasing decisions, and the ICCT is now planning a 2013 update once full-year US Department of Transportation data has been made available, processed and analysed.
“This study should interest anyone working to reduce the environmental footprint of the aviation sector,” said Rutherford.