The environmental challenge to aviation is nothing new. The industry has in the past been dismissive and defensive but is now moving towards constructive. Technology and innovation are finally delivering the green shoots of sustainability. FINN editor-in-chief Alan Peaford takes a look.

I still remember the guilty pleasure of hearing Concorde roar past my office which sat below London Heathrow’s flightpath. Others were not so keen. Even today, when protesters roll out to halt or delay the development of more airports, noise is the major issue.

More recently it is emissions that have caught attention. Aviation is responsible for more than 2% of global greenhouse gas emissions and 3% of Europe’s. Defensively, we would point out that a single cow, on average, releases 70 to 120 kgs of methane per year, and globally there are approximately 1.5 billion cows and bulls, which leads to lot of extremely harmful greenhouse gas — especially since methane is said to be 23 times more harmful than carbon dioxide.

Admitting the problem

However, the industry has realised that it has a problem. Aviation is the victim of its own success.

Demand for air transport is continually growing and, if this demand is to be met with all the attendant benefits, society must also accept the costs. At the same time, because of the finite nature of the resources upon which aviation relies, the industry has recognised that it is more realistic in the medium term to think how best to improve the sustainability of air transport, rather than it achieving sustainable development.

While Europe focused on penalty charges, eventually the global body representing 191 of the world states, ICAO, addressed the issue arguing that only a global solution would work.

IATA – representing the airlines – backed the new initiative. ICAO’s Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) is designed to complement the basket of mitigation measures the air transport community had already been pursuing to reduce CO2 emissions from international aviation (although a lot of these were driven by the high cost of fuel, so there were financial benefits too).

Implementation of CORSIA will begin with a pilot phase from 2021 through 2023, followed by a first phase, from 2024 through 2026. Participation in both of these early stages will be voluntary and the next phase from 2027 to 2035 will see all states on board.

The demands of the airlines – and their respective governments – to comply has seen pressure extended throughout the supply chain.

Alternative fuels

Saving weight is key to saving fuel and therefore reducing emissions. The increased use of composites is just one of the technical and operational improvements and advances in the production that is already making an impact.

Fuel is the largest cost for operators. A Boeing 747 gulps a gallon of fuel every second. The oil industry has stepped up to the plate, and begun to look at the use of sustainable alternative fuels for aviation.

Away from the oil majors, other institutions are breaking new ground. The Masdar Institute in Abu Dhabi – in association with Etihad Airways, Boeing, Takreer, Safran and General Electric –   announced in September that its flagship project, the seawater energy and agriculture system (SEAS), had reached a critical milestone in its development of sustainable aviation biofuels through the first harvest of the biofuel feedstock,  a local salt-tolerant and oil-rich plant called Salicornia.

Harvesting the Salicornia is the first in a series of steps before the oil collected from its seeds is ready to be refined. The steps include drying and grinding the plants, winnowing out the seeds, extracting the oil from the seeds by pressing, and finally cleansing the oil to remove any impurities.

In February next year the clean Salicornia oil is to be processed at the Takreer Research Center for conversion into aviation biofuel. Once the process is complete, the biofuel will be mixed at low concentration with regular jet fuel to power a flight by Etihad Airways on a Boeing aircraft.

Australian airline Qantas has already committed to flying its Los Angeles to Sydney flights with a 50% bio-fuel by 2020. UK low cost carrier Easyjet says its emissions have reduced by more than 31% per passenger kilometre since 2000. Over the next five years it is targeting a 10% reduction from today’s performance and a 38% improvement from 2000.

Greener engines

Engine makers have also been hard at it. Reviving the concept of open rotor engines and geared turbo fans is promising significant savings with the introduction of new powerplant for the Airbus neo and the Boeing MAX narrow bodies.

This focus has been from Clean Sky, a public-private partnership aimed at developing innovative, cutting-edge technology to reduce CO2, gas emissions and noise levels produced by aircraft. The programme – Europe’s largest research initiative – has reported that researchers have been able to achieve 40% fuel burn reduction compared to modern aircraft, as well as reducing noise levels to below those in today’s cutting-edge engines.

Meanwhile, the disruptive technologists are at work with a clear intention to remove the need for fossil and biofuels all together.

It is the electric aircraft!

Airbus is looking to put its flying taxi in the air next year, after CityAirbus conducted successful ground tests of the electric power system that it’s using to propel the vehicle through the air.

The CityAirbus craft is a vertical take-off and landing craft that uses a four-rotor design, and that would be able to take up to four passengers on short flights in dense urban areas, with the aim of connecting major transportation hubs including train stations and airports. It’s designed to be pilot-operated at launch, but to eventually transition to being a fully autonomous vehicle once the tech catches up.

In Dubai, it may already be there. The unmanned Volocopter, undergoing flight tests right now, is set to take two passengers at around 50kmh over the often congested roads of the UAE city.

In the USA, a start-up technology firm called Zunum Aero backed by Boeing and Jet Blue is building a fleet of hybrid electric jets to sell to major carriers for service on densely travelled regional routes such as San Francisco to Los Angeles or Boston to Washington DC. The early models are expected to take up to ten passengers 1000kms on a single charge.

Real change

Of course,  even that doesn’t compare with the feat of Bertrand Piccard and André Borschberg, who last year completed the first circumnavigation of the globe with no fuel. With their Solar Impulse solar-powered aircraft, they flew 40,000 km to promote the use of clean technologies, stopping on the way to deliver the powerful message that the real change will come from outside the industry.

Piccard said: “It’s quite logical really – it’s not the people who are selling the best candles who invented the lightbulb; it’s other people.”

So, it will happen, and in a way, I quite look forward to the day I can look out of my window on the busy flightpath to a major London airport and listen to the gentle swoosh as air transport goes about its business.

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