Airline Contrail Index
Latest update: December 2024
The first step to solving any problem is to acknowledge it exists. With the Airline Contrail Index, we track public contrail announcements to highlight airlines that set contrail reduction targets, participate in trials, help advance the science, or simply acknowledge the existence of contrail warming impact. We do this to provide visibility of airline contrail climate action, to raise awareness around the issue, and to inspire more airlines to address their non-CO2 effects.
December 2024: Of the thousands of airlines worldwide, THIRTYFIVE airlines have made it into the index.
The Airline Contrail Index is divided into four tiers - Platinum, Gold, Silver, and Bronze - reflecting the airlines’ level of engagement in contrail management. Please note that the index reflects what has been publicly communicated and does not include airline contrail activities that are not (yet) public. Also, note that the overall climate goal is to get aviation to net zero as fast as possible, and while contrail management is a cheap and easy way to get rid of a lot of warming, it must never be at the expense of decarbonization. Aviation’s CO2 emissions and non-CO2 emissions (including contrails) must always be addressed in parallel.
Only one airline made it to the top tier of the index, 17 made it to the gold tier, 10 are in the silver category, and seven received bronze.
Contrails are mainly a North American and European problem, so it is reassuring that 20 airlines in the index are from Europe, while 11 are from North America. Three Asian airlines are involved in contrail mitigation, while a single airline from Africa made the list.
With 20 entries, the full-service airline category tops the index, followed by 10 low-cost airlines, and five cargo carriers, which have a lot of activity at night when contrails are always warming.
Links to public announcements about airline involvement in contrail management:
PLATINUM - Contrail reduction targets, participation in trials, and collaborating with scientists:
DELTA AIR LINES collaborates with MIT (Massachusetts Institute of Technology) and Google Research to avoid making persistent contrails. They are also the first airline to set contrail reduction targets: 80% reduction by 2035 and 100% reduction by 2050.
GOLD - Participating in trials at scale and collaborating with scientists:
AIR CANADA is involved in contrail science by participating in the In-service Aircraft for a Global Observing System (IAGOS) and committed to Airlines for America’s acknowledgment of the need to address contrail warming.
AIR FRANCE has launched a webpage detailing all the non-CO2 impacts the airline is responsible for and all the contrail management projects Air France is involved in with Météo France, CICONIA, etc. More airlines should do the same.
AMERICAN AIRLINES is involved in research with Google Research and Breakthrough Energy and is a member of the Contrail Impact Task Force. In 2023, AA is also participating in research with flight planning software company Flightkeys.
CATHAY PACIFIC is involved in contrail science by participating in the In-service Aircraft for a Global Observing System (IAGOS).
CHINA AIRLINES is involved in contrail science by participating in the In-service Aircraft for a Global Observing System (IAGOS).
DISCOVER AIRLINES is involved in contrail science by participating in the In-service Aircraft for a Global Observing System (IAGOS).
EASYJET participates in the big Ciconia project involving contrails mitigation test flights, and more. EasyJet also sent a letter to the EU urging them to include more airlines in future reporting of non-CO2 climate impacts including contrails.
ETIHAD AIRWAYS is working with software company Satavia and others to adjust flight paths to avoid making condensation trails.
HAWAIIAN AIRLINES is involved in contrail science by participating in the In-service Aircraft for a Global Observing System (IAGOS) and committed to Airlines for America’s acknowledgment of the need to address contrail warming.
IBERIA is involved in contrail science by participating in the In-service Aircraft for a Global Observing System (IAGOS).
ICELANDAIR is a partner airline in the EU-funded CONCERTO project, which aims to introduce non-CO2 impact management into daily operations. Icelandair has also worked with Satavia on contrail mitigation trials.
KLM is working with software company Satavia and others to adjust flight paths to avoid making condensation trails.
LUFTHANSA has long collaborated with the German Aerospace Center, DLR, and others on condensation trail research and trials. Lufthansa is also part of the German 100 Flights program.
SOUTHWEST AIRLINES is a member of the Contrail Impact Task Force, which was formed in 2022 for industry players and scientific institutions to collaborate on best practices. The airline is also supporting GE Research in developing a new contrail prediction system and working with Google Research on their contrail systems.
SWISS AIR participates in the big Ciconia project involving contrails mitigation test flights, and more.
TUI is collaborating with Austrian flight planner Flightkeys and others to mitigate aviation’s non-CO2 emissions by avoiding contrails. TUI is also part of the German 100 Flights program.
UNITED AIRLINES is a member of the Contrail Impact Task Force, which was formed in 2022 to allow industry players and scientific institutions to collaborate on best practices. United also runs contrails trials with Boeing and NASA.
SILVER - Collaborating with scientists and/or participating in small-scale trials:
ALASKA AIRLINES is a member of and economic contributor to the Contrail Impact Task Force, which was formed in 2022 to allow industry players and scientific institutions to collaborate on best practices.
AMELIA, a regional French airline, is working with Thales to reduce its environmental footprint - including the climate impact from condensation trails. In June 2024, Amelia started conducting live contrail avoidance trials.
BRITISH AIRWAYS is participating in contrails mitigation research with Imperial College London and Breakthrough Energy, Carrie Harris, BA’s Director of Sustainability, says in this interview.
CONDOR is one of 12 operators that have worked with British company Satavia to optimize 65 flights for contrail management and prevent surface warming, equating to over 2,200 tons of CO2e. Condor is also part of the German 100 Flights program.
DHL is a cargo airline that typically flies a lot at night when contrails are most warming. DHL is a part of the German 100 Flights program.
EUROPEAN AIR TRANSPORT (EAT) is a cargo airline that typically flies a lot at night when contrails are most warming. EAT is part of a group that collaborates with the German Aerospace Center, DLR, on contrails management, which they describe here. EAT is also part of the German 100 Flights program.
KENYA AIRWAYS is one of 12 operators that have worked with British company Satavia to optimize 65 flights for contrail management and prevent surface warming, which equates to over 2,200 tons of CO2e. It’s the first African airline to engage in contrail management.
SUNEXPRESS is one of 12 operators that have worked with British company Satavia to optimize 65 flights for contrail management and prevent surface warming, which equates to over 2,200 tons of CO2e.
VIRGIN ATLANTIC is a member of the Contrail Impact Task Force, which was formed in 2022 to allow industry players and scientific institutions to collaborate on best practices.
VUELING is one of 12 operators that have worked with British company Satavia to optimize 65 flights for contrail management and prevent surface warming, which equates to over 2,200 tons of CO2e. This was mentioned in IAG’s Non-Financial Information Statement 2023. Vueling has engaged Estuaire to understand and monitor its non-CO2 emissions.
BRONZE - Publicly admitting the existence of climate impact from contrails:
ATLAS AIR is a member of the trade organization, Airlines For America (A4A), and, through A4A’s April 2024 Industry Insight, is committed to addressing non-CO2 emissions from aviation, including contrails.
FEDEX is a member of the trade organization, Airlines For America (A4A), and, through A4A’s April 2024 Industry Insight, is committed to addressing non-CO2 emissions from aviation, including contrails.
JETBLUE AIRWAYS is a member of the trade organization, Airlines For America (A4A), and, through A4A’s April 2024 Industry Insight, is committed to addressing non-CO2 emissions from aviation, including contrails.
RYANAIR has not announced participation in any specific contrail projects, but in their 2023 Sustainability Report, Ryanair calls out for more work to be done on contrails and other non-CO2 impacts. More airlines should at least acknowledge the existence of these impacts. Ryanair also sent a letter to the EU urging them to include more airlines in future reporting of non-CO2 climate impacts, including contrails.
SCANDINAVIAN AIRLINES (SAS) is working with DLR, the German Aerospace Center, on a study involving sustainable aviation fuels, but also mentions that SAF reduces the climate impact of contrails.
UPS is a member of the trade organization, Airlines For America (A4A), and, through A4A’s April 2024 Industry Insight, is committed to addressing non-CO2 emissions from aviation, including contrails.
WIZZ AIR is a co-signer of the May 7, 2024, letter from three low-cost airlines to the European Commission urging them to include non-European airlines in the future reporting of non-CO2 climate impacts – including contrails.
The index is updated as needed. We have not been able to find other airlines publicly announcing they are involved in contrail research or trials, or simply acknowledging the climate challenge of contrails. Please let us know if we have missed any public announcements from other airlines.
ARCHIVE:
August 2023: 9 airlines in the index: Alaska, American, Delta, Etihad, KLM, Lufthansa, Southwest, United, Virgin Atlantic.
September 2023: 11 airlines in the index. Added: Amelia, European Air Transport.
October 2023: 12 airlines in the index. Added: SAS.
November 2023: 17 airlines in the index. Added: Air France, British Airways, EasyJet, Icelandair, Swiss.
April 2024: 29 airlines in the index. Added: Air Canada, Atlas, Condor, FedEx, Hawaiian, JetBlue, Kenya, Ryanair, SunExpress, TUI, UPS, Vueling.
May 2024: 35 airlines in the index. Added: Cathay Pacific, China Airlines, DHL, Discover, Iberia, Wizz Air.