With growing concerns around global warming and the increased usage of sustainable energy resources, hybrid aircraft could play a bigger role in the future. The aerospace sector has undoubtedly made impressive strides since the 1950s in terms of increased power and efficiency of engines. However, more recent studies indicate that engine technology could reach thermodynamic limits.

This means a more reasonable investment in the amount of energy we can extract from carbon-based fuel. More air travel and more aircraft in the sky will lead to increased fuel consumption and greenhouse gas emissions unless we find a suitable fossil fuel substitute.

Aviation By The Numbers

The global aviation industry accounts for 2.4% of the total carbon-dioxide emissions and about 12% of the greenhouse gases (Source: ATAG). These numbers are expected to increase due to rising demand for air travel which requires additional capacity. Experts predict that by 2028, the total passenger kilometres could increase by more than 60% to 12 trillion.

At the same time, the size of the global fleet will expand by 43% to more than 39,000 aircraft. The International Civil Aviation Organization (ICAO) predicts that by 2050, emissions from aviation could increase by a staggering 300%. The global GHG production will also likely rise if we do not make a real attempt at finding an alternative to fossil fuels.

Hybrid Aircraft And Hybrid Vehicle Technology

We’ve covered several developments in hybrid aircraft technology and while many are promising, a complete solution to the global emissions problem is still a few years away. It will be some time before we see a commercial jet fully powered by something other than fossil fuels.

Some pioneering aerospace companies are taking a page from the automotive industry to design and develop hybrid aircraft. As with electric cars, the propulsion systems are part-internal combustion and part-electric. While they certainly fill the gap in the interim, truly sustainable aviation will depend on developing a fully electric or hydrogen-powered aircraft.

Electrification Of Transport

While hybrid cars don’t reduce emissions as much as fully electric models, it is almost 50% less compared to petrol or diesel cars. In terms of the aviation sector going hybrid, they must still overcome several engineering challenges and regulatory approval. That said, hybrid aircraft as an alternative will likely be available much sooner than a fully electric aeroplane.

Research into electrifying transportation is a global effort in reducing greenhouse gas emissions to counter widespread drought and increased sea level. Despite every country and industry promising to do their part, carbon emissions continue to rise.

Global Carbon Project

According to a report from the Global Carbon Project, carbon emissions are up by 2.7% compared to last year. The International Air Transport Association indicate that emissions from the aviation sector are up by 26% since 2013.

Carbon Offsetting And Reduction Scheme

Whether you ‘believe’ in global warming or not, we cannot solely rely on fossil fuels to power the globe for eternity. There are just too many variables to suggest that the supply is endless or that using fossil fuels is ‘safe for the environment’.

With the rising pressure to at least stabilise the emissions problem, the aviation sector needs to find solutions in the next few years. Failing to do so will result in penalties under an agreement sponsored by the United Nations called the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA). This agreement requires airlines to cap emissions at 2020 levels.

Hybrid Aircraft Development

A lot has happened in the world of sustainable aviation as we’ve seen several clean-burning aircraft take to the skies. While many are only prototypes and test flights, it remains an incredible milestone for companies leading from the front. Some of the more recent developments include the following:

• Pipistrel’s Alpha Electro (electric light sport aircraft) took off in Australia
• The Extra 330LE, an electric aerobatic plane, seamlessly towed a glider into the sky
• Airbus Group’s E-Fan technology demonstrator crossed the English Channel back in 2015
• Faradair’s BEHA M1H variant readies for production as early as 2025

Related: ‘Los Angeles-based Ampaire: The largest hybrid-propulsion plane to ever take flight’

Final Thoughts

While global warming remains a hotly debated topic, there is sufficient evidence indicating that climate change is accelerating. Considering the sheer number of flights globally, the aviation industry can’t afford to wait too long in addressing the glaring emissions problem.

According to Tom Cooper, Vice President at CAVOK, “Economic growth in both mature and developing economies is driving solid increases in fleet size and MRO, although significant regional differences exist.”

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