by
CNN
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The basic design of commercial aircraft hasn’t changed much over the past 60 years. Modern aircraft such as the Boeing 787 and Airbus A350 have the same general shape as the Boeing 707 and Douglas DC-8, which were built in the late 1950s and enhanced the “tube and wing” form factor still in use today.
This is because commercial aviation prioritizes safety, favoring tried and tested solutions, and because other advances – in materials and engines, for example – mean that traditional design is still relevant.
However, while the industry is desperately looking for ways to reduce carbon emissions, it faces a somewhat more difficult challenge than other sectors precisely because its core technologies have proven difficult to break away from. Maybe it’s time to try something new.
One suggestion is a “hybrid wing fuselage”. The all-new aircraft’s shape looks similar to the “flying wing” design used by military aircraft such as the famous B-2 bomber, but the blended wing has a larger midsection. Boeing and Airbus are tweaking that idea, as is a third player, California-based JetZero, which has set an ambitious goal of having a mixed-wing aircraft in service by 2030.
“We feel very strongly about the path to zero emissions in large aircraft, and a mixed-wing airframe can deliver 50% less fuel burn and emissions,” says Tom O’Leary, JetZero co-founder and CEO. “This is an amazing leap forward compared to what the industry is used to.”
The concept of blended wings is not at all new, and the first attempts to build aircraft of this design date back to the late 1920s in Germany. American aircraft designer and industrialist Jack Northrop created a jet-powered flying wing design in 1947, which inspired the B-2 of the 1990s.
As a sort of hybrid between a flying wing and the traditional “tube and wing”, the combined wing allows the entire aircraft to generate lift, which reduces drag. NASA says This shape “helps increase fuel economy and creates larger load areas (cargo or passenger) in the midsection of the fuselage.” The agency tested it with one of its experimental aircraft. X-48.
Through nearly 120 test flights between 2007 and 2012, two remotely controlled X-48 drones demonstrated the feasibility of the concept. “An aircraft of this type will have a wingspan slightly larger than a Boeing 747 and can operate from existing airport terminals,” the agency says, adding that the aircraft will also “weigh less, generate less noise and emissions, and have a lower operating cost.” Equally advanced conventional transport aircraft.
In 2020, Airbus built a small mixed-wing prototype, about six feet long, indicating interest in pursuing a full-size aircraft in the future. But if the shape is so functional, why haven’t we moved on to building aircraft based on it yet?
According to O’Leary, there is a major technical challenge holding manufacturers back. “It’s the pressure of a non-cylindrical fuselage,” he says, pointing to the fact that a tubular plane is better able to handle the constant cycles of expansion and contraction that come with each flight.
“If you think of ‘tube and wing’, it separates the loads – you have compressive load on the tube, bending loads on the wings. But a wing spanner basically blends those together. Only now can we do that with composite materials that are light and strong at the same time.”
Such a radically new shape would make the interior of the aircraft look very different from today’s wide-body aircraft. “It’s just a much wider body,” O’Leary says. “Your typical single-aisle plane has three seats by three, but this tube type is shorter and wider. You can have the same number of people, but you might have 15 or 20 rows across the cabin, depending on how it’s configured for each particular airline.
“This gives them a whole new canvas to put it on. I think it will be amazing to see what their interpretation of this much broader space will be like.”
O’Leary says the closest equivalent in terms of size would be the Boeing 767, a widebody, twin-engine airliner that appeared in the 1980s that typically carried about 210 passengers. It is still produced as a freighter but has been replaced by the Boeing 787 as a passenger plane. It also has a modernized military version, the KC-46, which is used by the US Air Force for mid-air refueling.
Likewise, JetZero wants to develop three different types at once: a passenger plane, a cargo plane, and a fuel tanker. The wing’s blended shape matches well with the latter’s shape that the USAF has JetZero has just awarded $235 million To develop a full-scale display and performance validation of a blended wing concept. The first flight is expected by 2027, which means a military version of the aircraft is set to lead the way and possibly support the development of commercial models.
However, building an entirely new aircraft from scratch is a daunting task, and JetZero’s goals seem ambitious, given that the entire certification process for even a variant of an existing aircraft can take years. One advantage JetZero has in this area is that the aircraft will initially borrow engines from existing narrow-body aircraft, such as the Boeing 737 — although the plan is eventually to migrate to a completely zero-emissions hydrogen-powered propulsion system, which would It will require new engines that have not yet been developed.
JetZero doesn’t have any orders for its plane yet, but O’Leary says airlines are interested. “We’re already talking to all the major airlines globally, because they’re excited to hear about the efficiency gains.”
It remains to be seen whether a 50% reduction in fuel consumption is actually possible. both of them NASA Airbus has specified a more modest 20% for its designs, while the US Air Force says a mixed-wing aircraft can “improve aerodynamic efficiency by 30% at least On existing Air Force tanker and transport aircraft.
“It is important to note that although an integrated wing fuselage can reduce drag and increase fuel efficiency, the actual benefits depend on the specific design, configuration and operational conditions,” says Billy Miles, aviation analyst at AviationValues, a consultancy.
“Extensive aerodynamic testing and optimization is essential to fully realizing the drag-reducing capabilities of this innovative aircraft design. It will be difficult to determine an exact percentage of fuel reduction without the necessary testing,” he adds.
according to Miles, the compact wing design is a “revolutionary” idea with potential, but it comes with a number of hurdles, namely increased aerodynamic complexity that can make design and testing difficult, a series of regulatory and certification challenges, and a shape that may not be suitable for the infrastructure. current airport.
“Blender-wing aircraft hold enormous promise as game-changers in the aviation industry, offering the potential for improved fuel efficiency, enhanced payload capacity, and innovative control systems. However, addressing aerodynamic complexities, ensuring structural integrity, and overcoming regulatory hurdles, Adapting airport infrastructure presents enormous challenges that must be overcome in order to become a reality.To enter service is “unimaginable”.
According to Richard Aboulafia, aviation analyst at consulting firm Aerodynamic Advisory, while not all of JetZero’s claims can be verified, “the idea of a blended wing-fuselage has been very attractive for years, and it looks like they’ve done some very interesting things.” research. My colleagues and I consider this very promising.”
He worries the company is mostly a “design shop” at the moment, but thinks the project could get off the ground with the help of contractors. “There is definitely room for someone who really wants to add value to the industry,” he says.
