Realising sustainable aviation in the era of climate change

Aviation is one of the greatest innovations in modern human history. Since the Wright brothers, Wilbur and Orville, became the first people to fly a heavier-than-air, power-controlled machine for 59 seconds over a distance of 852ft, an extraordinary feat, air transportation would forever change human activity.

From that December 17, 1903 day with the American inventors’ plane, aviation is today an indispensable segment of human activity and life on Earth.

While the Wright brothers are recognised for their amazing achievement, the Englishman Sir George Cayley (1773-1857) is known as the inventor of the aeroplane and one of aviation’s most significant pioneers.

His work would earn him the title of Father of Aeronautics or Father of Aerial Navigation.

Incredibly, the airplane building Wright brothers’ unprecedented success in Kitty Hawk, North Carolina, was not appreciated by all.
Many in the press and fellow flight experts at home were reluctant to believe the brothers’ claims at all.

As a result, Wilbur set out for Europe in 1908, where he hoped he would have more success, convincing the public and selling airplanes.

Indelible mark

In France, Wilbur joined by Orville in 1909, found a much more receptive audience, making many public flights and giving rides to officials, journalists and statesmen.

The Wrights began to sell their airplanes in Europe, before returning to the US and became wealthy businessmen, filing contracts for airplanes in Europe and the US.

The rest, as they say, is history.

Today, long after the Wright brothers left an indelible mark, aviation is a key driver of economic growth, supporting trade, business and tourism. In 2014, research estimated that aviation supported 63 million jobs and $2.4 trillion in Gross Domestic Product.

Aviation, however, also has a huge impact on the climate by contributing carbon dioxide and other greenhouse gases. Conversely, climate change also impacts aviation by increasing the frequency and severity of weather events, which can disrupt flight operations.
Aviation is the second largest source of greenhouse gas emissions in transportation. In 2023, aviation contributed 2.5 per cent to global carbon dioxide emissions. Emissions from aviation are projected to increase in the coming decades.

Climate change’s impact on aviation include severe weather events such as hurricanes, heatwaves, and flooding, which can disrupt flight operations. Extreme weather events can make it harder to fly. Climate change can impact tourism demand, which can affect the number of passengers and flights.

Efforts are being made to reduce aviation’s impact on climate change by using sustainable aviation fuels, improving airframes and engines and optimising flight trajectories. There have been efforts towards reducing the need for transport, developing new power generation technologies, such as electric and hydrogen and improving operational resilience.

A number of organisations are working to reduce aviation’s impact on climate change. They include the International Civil Aviation Organisation (ICAO), World Meteorological Organization (WMO), the Intergovernmental Panel on Climate Change (IPCC) and the European Union Aviation Safety Agency (EASA).

“Many of us feel guilty when we fly because it is a very obvious source of carbon emissions. But we don’t perhaps feel the same guilt when we walk into a new building, even though global concrete manufacturing emits closer to 8 per cent. Or when we jump in a petrol car or turn on our central gas heating,” wrote Mark Maslin and Iain Hanson in The Conversation recently.

Maslin is a professor of natural sciences at University of London and Hanson is an honorary professor at the Bartlett School of Sustainable Construction.

Reduced global emissions

“This is because aviation is a very visible symbol of or high-carbon consumption and, until now, the aviation industry has been slow to engage with the climate change agenda. According to the United Nations, we are looking at global warming of up to just over 3C which would be disastrous for the planet and our societies,” they say.

Human-caused global warming has just passed 1.5C. Science suggests that we could keep close to this temperature if we reduced global emissions by 2030 and reached net zero by 2050.

Post-Covid, aviation continues to regroup and grow and is set to be a trillion-dollar industry by 2030, but it is incredibly vulnerable to the effects of climate change.

The aviation industry is predicted to grow at 4 per cent per year. Without meaningful action, net zero by 2050 will never be achieved and aviation needs to reduce its carbon footprint now.

On the other hand, clear turbulence events in the North Atlantic have increased by 55 per cent since 1979 and prominent incidents have resulted in deaths, serious injury and damage to aircraft.

Extreme weather events such as extreme rains and flooding have affected Middle Eastern airports and snowfall has crippled airports in the United Kingdom, causing considerable disruption.

Maslin and Hanson have highlighted five key steps focusing on decarbonisation that also make aviation more sustainable and improve operational efficiency and safety.

The first step would be to optimise flight planning and airspace. Airlines are already trying to select most fuel-efficient routes and altitudes using advanced flight planning systems, AI and optimisation software.

Advanced aerodynamics

However, future route optimisation could reduce turbulence events and the production of contrails with associated radiative forcing, increasing comfort and safety for passengers and contributing positively to the environment.

Optimising aircraft separation and air traffic control flow management can prevent aircraft bunching up and arrival delays because planes are forced into holding patterns, waiting their turn to land at the airport and burning large amounts of fuel.

Secondly, making operations more sustainable through the latest generation commercial aircraft utilising advanced aerodynamics and engine technology saves a significant amount of fuel and emissions from previous types.

Airlines must invest in modern fuel-efficient aircraft and retrofit existing aircraft to improve efficiency.

Thirdly, the biggest source of emissions in aviation is the burning of kerosene. Airlines need to transition from conventional to sustainable aviation fuel (SAF), covering a whole range of technology from biofuels derived from plants, animals or waste to synthetic fuels such as artificial kerosene. Some SAFs could lower carbon dioxide emissions by 20 to 98 per cent compared to conventional fuel.

Fourthly, airports can become much more sustainable by using renewable energy, such as solar or wind energy for airport operations, including powering the terminals and equipment. Renewable energy can be used for ground equipment and airplane support, by having electric airplane tugs, baggage loaders and catering trucks.

Ground operations can be improved to reduce emissions such as minimising aircraft engine idling time during taxiing and using reduced engines for taxiing around the airport.

The industry has an exciting opportunity to design and develop the next generation of sustainable airports. There are 575 existing or new airport projects around the world, at a total value of US$488 billion, with many more planned over the next 20 years.

Finally, the aviation industry can make passengers more sustainable by redefining the passenger experience from door to door, not just the time spent at the airport or on a plane. This could include luggage pick-up from home and incentives to use public transport to the airport.