Flyers concerned about their carbon footprint may be interested in the results of a new report which found that Chinese carrier Hainan Airlines and Japan's All Nippon Airways (ANA) were the most fuel-efficient airlines for transpacific flights in 2016. The most polluting airline in the same category? Qantas Airways.
In a report released by the International Council on Clean Transportation (ICCT), 20 airlines operating nonstop flights between the mainland US and East Asia and Oceania were ranked on the fuel-efficiency of their transpacific operations.
Tying for first place with an average fuel efficiency of 36 passenger-kilometers per liter of fuel, Hainan Airlines and ANA topped the ranking.
At the other end of the spectrum, Qantas Airways landed at the bottom of the heap, burning an average of 64 percent more fuel per passenger-kilometer than the top performers, or 41 percent below the industry average.
For the report, researchers looked at aircraft fuel burn, seating density, passenger load factor, and the freight share of total payload.
Overall, cargo or freight share emerged as the most significant factor in the overall fuel-efficiency rating: While cargo on passenger flights increases fuel burn, it improves fuel efficiency per unit of mass moved.
Analysts credit Hainan's efficiency rating to its advanced fleet: 81 percent of its available seat kilometers were aboard the Boeing 787 Dreamliner aircraft.
Meanwhile, though flights operated on ANA aircraft had higher fuel burn, the Japanese airline offset its fuel inefficiencies by moving more payload -- three times as much belly freight per passenger as Hainan.
By contrast, Qantas operated the most fuel-intensive aircraft and reported low load factors for both passengers and freight, says the report.
Here's how the airlines ranked for transpacific, non-stop flights in 2016:
3. Air New Zealand
4. EVA Air
5. China Airlines
6. Air China
7. Virgin Australia
9. American Airlines
10. Japan Airlines
12. United Airlines
13. China Southern
14. Cathay Pacific
15. China Eastern
16. Philippine Airlines
17. Singapore Airlines
19. Korean Air