. 2020 Jun 25;271:123000. doi: 10.1016/j.jclepro.2020.123000

Table 1.

Summary of some illustrative case airlines’ greening policies and practices.

Selected leading airlines	Key features	Nature of greening principle	Nature of greening policies and activities	Synthesised from sources:
BA, UK	It was a British state-owned national airline and then privatised. Today, it is a major international airline with over 40 million customers and services to over 70 nations around the globe.	BA’s plan demonstrated commitment to reduce the environmental impact of its business activities.	• In January 2020, BA decided to offset carbon emissions for all domestic flights via investments in carbon-reduction projects encompassing reforestation and rainforest protection schemes. • Investment in sustainable fuels to help usher in a new era of “green” aviation. • Adoption of and investment in fuel-efficient aircraft such as the use of the Airbus A350 which is 50% quieter and 25% more fuel efficient than the similar-sized fleets. • Through collaborative partnership, the airline is working to design centres that transform commercial and domestic waste into renewable jet fuel for its aircraft. • Ongoing fuel-saving initiatives such as optimising flight routes and minimising the weight of aircraft have led to a reduction of carbon emissions of over 360,000 tonnes since 2014. • Participatory member of the EUETS from the outset in 2012.	BA, 2020a; BA, 2020b; Airfranceklm (2020).
Air France–KLM	The Air France–KLM Group is an outcome of the 2004 merger between Air France and KLM. One of the safest global airlines.	Air France and KLM’s sustainability strategy for 2030 was underpinned by the United Nations Sustainable Development Goals (SDGs)	• Air France–KLM decreased its noise footprint by 35% from 2000 to 2018 and enhanced energy efficiency for each passenger/km by 21.6% from 2011 to 2018. • KLM seeks to reduce CO₂ emissions by over 10% by 2030 relative to 2018 levels. • It also seeks to obtain a CO₂-neutral ground operation and reduce waste by 50% relative to 2011 levels. • KLM is part of the EU’s emissions trading system. • Champion fleet renewal to help reduce CO₂ emissions. Indeed, some new aircraft are producing 35%–40% less CO₂ emissions as well as producing less noise. On the noise, for instance, the Boeing 787-9 Dreamliner is around 40% quieter relative to comparable aircraft.	KLM, 2019a, 2019b; Air France–KLM, 2019.
Turkish Airlines	Turkish Airlines headquartered in Istanbul is the national airline of Turkey. Founded in the 1930s, it operates to over 300 destinations across the globe including Africa, Asia, Europe and North America. In 2018, it was regarded as the carrier “that Connects Africa to the World” (Turkish Airlines, 2019, p. 13).	Among its visions, it seeks to become the airline with zero major accidents or crashes.	• Broadly, the company emphasis is on “stakeholder inclusiveness”. • In 2008, the airline forged collaboration with IATA Green Team toward implementation of the Fuel Efficiency Program to help improve fuel efficiency and decrease carbon emissions. • Involved in over 70 projects to optimise operations and thereby helping to decrease the carbon footprint. • Fostering investment in new technologies with least harmful effects on the natural environment. • Since 2013, the airline has been certificated by ISO 14001. • Integrated approach to reduce electricity, natural gas, fuel and paper consumption. • Seeks to reach 120 million passengers by 2023 and currently regarded as one of the biggest and most state-of-the-art airlines of the world with over 500 efficient and environmentally friendly aircraft.	Turkish Airlines (2019), 2020.
Ethiopian Airlines	Started operations in the 1940s and remains one of the most successful state-owned airlines in the world.	Focused on cutting emissions and utilising fuel-efficient aircraft.	• In 2018, in tandem with the United Nations Environment Programme, the global authority on the environmental agenda launched the “Plant one tree for every passenger flown” project which is expected to lead to around nine million trees being planted (United Nations Environment Programme (2018). • It also launched “Greening Ethiopian Airline business” which emphasised operational improvements and reducing waste. • Committed to tackling adverse environmental impacts via waste minimisation, pollution prevention measures, resource conservation and a green procurement strategy.	Ethiopian Airlines, 2020; United Nations Environment Programme, 2018.
Ryanair	Low-cost airline established in 1984 and headquartered (HQ) in Dublin.	Ryanair is regarded as the “greenest, cleanest airline” in Europe (Ryanair, 2020).	• Greater emphasis on technology use to minimise fuel use. • The airline operates high seat density in aircraft, decreasing fuel burn and emissions per passenger by around 14%. • Received delivery of new Boeing 737-800NG aircraft which allowed a 2% improvement in fuel consumption. • The airline operates “paperless cockpits” with pilots using tablets and electronic flight bags. • A “green HQ” in Dublin promoting paperless business practices, reducing waste and recycling. Firm commitment to become “plastic free” by 2023. • The use of mainly secondary and regional airports helps to minimise congestion and noise at major cities.	Ryanair, 2020a, 2020b.