Hydrogen fuel and supersonic travel

The development of new Sustainable Aviation Fuel (SAF) alternatives and supersonic flight are two of the issues that I predict will influence commercial aviation this year.

Prediction 1: Demand for hydrogen fuel will grow – starting the trajectory towards 70 million tons a year by 2050

Aviation is responsible for around 2.5% of global CO2 emissions, with most aircraft powered by jet fuel. The European Commission predicts that by the middle of the 21st century, demand for flying could increase aviation’s greenhouse gas emissions by upwards of 300% over 2005 levels if no drastic measures are taken to reduce them.

So, it’s no surprise that most major commercial airlines are looking towards SAF alternatives, as they can reduce emissions by 80% according to the International Air Transport Association (IATA).

SAF can be made from several sources ranging from agricultural waste to carbon captured from the air. In fact, Virgin Atlantic has already made the leap to launch the first fully SAF powered transatlantic flight.

SAF is compatible with existing aircraft and fuelling infrastructure. However, high production costs and limited supply have slowed its adoption. It is estimated that SAF comprises less than 0.1% of all jet fuel currently used.

So, what other alternatives are available for commercial use?

With short-haul flights of fewer than 600 miles accounting for more than 17% of airline emissions, new technologies such as electric and hybrid-electric aircraft are growing in popularity. But electric aircraft are only suitable for short-haul flights, so what about the other 83%?

Hydrogen-powered aircraft are also being developed. Studies have found that hydrogen could play a central role in the future mix of aircraft and propulsion technologies. For long haul flights, such as transatlantic, hydrogen will be a much better option.

Such disruptive innovation will require significant aircraft research and development, particularly further development of liquid hydrogen tanks, and investment into fleet and hydrogen infrastructure.

Accompanying regulations and certification standards will be required to ensure safe, reliable and economic hydrogen-powered aircraft can take to the skies. However, even in its liquid state the volumetric energy density of hydrogen is less than half that of jet fuel. So, you either fly half as far on existing-sized fuel tanks, or you need fuel tanks that are twice the size.

One organisation already firmly in the race to full hydrogen powered flight is JetZero. JetZero is currently working on its own blended-wing aircraft design, called the Z5.

The Z5’s blended-wing design will ensure enough internal volume to accommodate zero-carbon emissions hydrogen fuel, but it is also designed to be 100% SAF compatible. JetZero hopes to build a full-sized demonstrator by 2027, achieve certification by 2029, and enter into service in 2030.

Big players in the commercial aviation industry are also tapping into this promising new development – with H2Fly, Universal Hydrogen and ZeroAvia to explore the retrofit of their regional aircraft fleet with zero-emission powertrains.

The potential of hydrogen doesn’t stop at replacing existing long-haul flights though – other startups are looking to take hydrogen to supersonic speeds.

Prediction 2: London to New York realisable in 2 hours by 2030 — as the Concorde’s descendants take to the skies!

When the last commercial flight on the Concorde landed on October 24^th 2003, in some ways commercial aviation took a step backwards. For over 20 years, we’ve been stuck at transonic speeds.

Now though, as Europe’s Vision for Aviation predicts globally a six-fold increase in passengers by 2050, faster flights are becoming attractive and a number of companies are looking to take advantage.

With United Airlines already having ordered a number of Boom Supersonic’s ‘Overture’ aircraft, the heir apparent to Concorde, and American Airlines following suit—it’s clear that major airlines are keen to tap into the future of supersonic, intercontinental commercial travel.

This time though, we aren’t stopping at supersonic. Atlanta-based aviation firm Hermeus is actively developing a reusable hypersonic aircraft for both military and commercial applications.

Hermeus’ technology demonstrator, Quarterhorse, eventually aims to achieve speeds in excess of Mach 4 and potentially even higher thanks to the organisation’s unique propulsion system design, Chimera, which is capable of transitioning from turbojet to ramjet modes. That dual mode capability means it can take off from a regular runway, get over the ocean, and then go hypersonic, avoiding noise and shockwaves that were a barrier to supersonic adoption the last time around.

But with climate change such a major concern, the question arises: will people one day be able to count on flying from Paris to New York in less than an hour without contributing to global warming?

These new designs are being explored to make aircraft fly faster, soar higher and now some are even designed to have a smaller environmental footprint.

Destinus is developing a prototype hypersonic hydrogen-fueled plane that aims to transport passengers from Sydney to Frankfurt in four hours and 15 minutes. While it may sound unrealistic in the near term, the company has already successfully flight-tested two prototype aircraft.

The commercial aviation industry needs to stay primed to capitalise on opportunities and mitigate against challenges in 2024

As the aviation industry launches into 2024, it will face a multitude of new opportunities and challenges – from new players in space, and taking hydrogen-fueled aircraft to new heights, to AI lowering the barrier, to predictive maintenance, and the rise of counterfeit parts entering the aviation supply chain.

Organisations in the commercial aerospace industry need to act swiftly to identify these opportunities and challenges, work to find a way to capitalise on the opportunities, and solve the issues at hand in order to keep ahead of the competition in 2024 and beyond.

• Rob Mather is vice president, aerospace and defence industries at IFS.