The workhorse plane of the future may look radically different to the familiar shape that has dominated the skies since the start of the jet age, according to Boeing, which is experimenting with a long, thin wing supported by struts from the fuselage.
The US manufacturer hopes its new design can be among the technologies that will help the industry meet its target of reaching net zero emissions by 2050.
Aviation accounts for more than 2 per cent of global carbon dioxide emissions, almost half of which come from single-aisle aircraft such as Boeing’s 737 and European rival Airbus’s A320 that are largely used for shorter and medium–haul flights.
This week’s Paris air show was dominated by orders for the latest models, which will be flying for another 25 years at least. But manufacturers are already shifting their focus to the technologies — like the unusual Boeing wing — that could replace today’s best-sellers.
New generations of aircraft have typically consumed 15-20 per cent less fuel than their predecessors, thanks largely to improved engines. Airbus’s single-aisle A321neo uses at least 20 per cent less fuel per passenger than older planes, according to the company.
With the next generation of planes, the stakes are much higher. Climate change presents a near-existential threat to commercial aviation. The industry has pledged to reduce its carbon emissions but not everyone is convinced the 2050 net zero target is achievable — a recent poll of industry executives by GE Aerospace found that 32 per cent doubt it can be reached.
Guillaume Faury, chief executive of Airbus, said this week that decarbonisation was one of the industry’s big challenges.
It is going to be “very difficult” for the industry to keep growing and meet the 2050 target, Sir Tim Clark, president of Dubai-based Emirates Airlines told the Financial Times ahead of the show. Although the airline industry is already trying to mitigate its environmental impact in terms of its operations, “we as an airline community have to do more than we’ve done in the past”, he added.
The industry is setting great store by “sustainable aviation fuels”, made from waste such as cooking oil and plants. While not fully carbon-free, supporters believe SAFs could bring rapid decarbonisation by replacing traditional oil-based fuels.
Industry trade group the International Air Transport Association estimates SAF could contribute 65 per cent of the reduction in emissions needed for aviation to reach net zero in 2050. Both Airbus and Boeing have pledged that their planes will be compatible to fly on 100 per cent SAF by 2030.
Some analysts believe faith in SAF could be misplaced. Nick Cunningham of Agency Partners described the 65 per cent target as “an irresponsibly big bet” in a note this week, adding that “SAF production is only growing slowly, and prices remain far too high”.
Boeing and Airbus are both looking to change their aircraft designs. The US manufacturer has been working with Nasa on the “transonic truss-braced wing”, and a full-scale prototype could be flying in five years.
Nasa has said the wing, when combined with other advancements in engines and materials, could cut emissions by 30 per cent. The collaboration includes a $425mn commitment from the space agency as well as $725mn invested by Boeing and its industry partners.
Stan Deal, the head of Boeing Commercial Airplanes, told the Financial Times in Paris that the company was “not starting at zero”. Boeing and the space agency have been researching the design for more than a decade.
“We have to prove that the optimism that we saw in the wind tunnel when scaled to full-scale flight translates,” he said. If it does, “it’s a platform that we could bet on as a potential for the next aeroplane”.
The company said no decisions had been made and that it was working on various technologies.
Airbus is also working on different options including new wings as it looks to a successor for its A320neo or A321neo models. The European group is also working on a hydrogen-powered aircraft.
Both plane makers are evaluating new engine designs from the main suppliers, which include Rolls-Royce, Pratt & Whitney and CFM International, the joint venture between France’s Safran and America’s GE Aerospace.
Rolls-Royce is continuing to develop its huge UltraFan engines, which incorporate several new efficiency-boosting technologies. The company said last month that it had successfully completed the first ground runs of its 140-inch-fan UltraFan demonstrator powered by 100 per cent SAF.
CFM is developing an open-rotor jet engine — a design with visible fan blades that are not enclosed as those on current jet engines. The so-called Rise programme — Revolutionary Innovation for Sustainable Engines — was unveiled two years ago.
Executives in Paris said the technology would lead to a 20 per cent reduction in emissions.
Net zero is “not a dream, it’s a goal”, Gaël Méheust, CFM chief executive, said before the show. “We not only have a part to play, we have to lead the way.”
Executives at Boeing and Airbus stressed that the efficiencies would have to be found in all aspects of aircraft design.
“It’s not just the engine,” said Christian Scherer, Airbus chief commercial officer. “It’s the engine integration, it’s our own technology, it’s aerodynamic improvements, lightweight materials, production technologies.”
Scherer argues a lot of progress towards decarbonisation can be made with the use of SAF and the replacement of older aircraft with more fuel-efficient planes.
“So if you are going to bring something new to the market in a market that has plenty of potential through SAF, through A320neos, you had better make it a really big bang,” he said, adding that “big bang sounds more like 30 per cent than 20 per cent” in terms of efficiency.
Boeing’s Deal believes efficiency gains need to be 20-30 per cent over the current generation of aircraft to warrant major investment.
“Think about the capex redeployment that occurs,” he said. “There is the Boeing side and then every airline. It requires that much benefit to get the pay-off of return long-term.”
Given the industry’s projected growth trajectory, however, some analysts remain sceptical whether touted efficiency gains will ultimately make a difference.
Cunningham said 20 per cent improvements would not be “remotely enough” for the industry to meet its net zero targets. “The percentage gain from the gradual replacement of the global fleet by more efficient aircraft would be more than offset by annual traffic growth as it went along.”