Spurred by increasing global demand for air travel, aviation emissions have been rising faster than those from rail, road, or shipping in recent decades. Solutions to invert the trend are slow-dripping: Sustainable Aviation Fuel, which can cut emissions on a flight by 80% when produced and used correctly, could represent two thirds of the reduction in emissions needed for aviation to reach its net-zero goal by 2050. But, it’s in short supply and in the best case scenario, SAF will have accounted for just 0.53% of all jet fuel use in 2024, a far cry from the levels required to make an impact.
While airlines and regulators scramble for ideas to decarbonize the industry, some engineers are suggesting that an entirely new type of aircraft shape is required to save big on fuel consumption and therefore emissions. This does away with the traditional “tube and wing” design that has been the mainstay of commercial aviation for 100 years, in favor of something called a “blended wing body,” in which the wing area takes up a large portion of the fuselage and creates a distinctive-looking plane.
In 2020, Airbus created a small scale, remote-controlled blended wing demonstrator, to test out a design the company said could save up to 20% of fuel. In 2023, California-based JetZero announced plans for an aircraft with a similar design, with capacity for over 200 passengers and has an ambitious target of entry into service by 2030.
Now, San Diego-based Natilus has joined the race with Horizon, a blended wing aircraft that is also meant to carry about 200 passengers while producing half the emissions and using 30% less fuel than current Boeing 737 and Airbus A320 aircraft — the models it’s aiming to compete with.
“The narrow body market, which is exactly where the Horizon fits in, is going to be the biggest market over the next 20 years,” says Aleksey Matyushev, CEO and co-funder of Natilus. “With all the challenges I think the industry is having, for the first time ever, I think there’s an opportunity to build a Boeing or an Airbus lookalike (equivalent).”
A new passenger experience
Natilus, which was founded in 2016, had previously announced a cargo-only, pilotless plane called Kona that also uses the same innovative shape. Matyushev says the blended wing body design originated in the 1990s from McDonnell Douglas, a major American aerospace manufacturer that merged with Boeing in 1997. Boeing never commercialized a blended wing plane, but studied the concept and produced an unmanned prototype, the X-48.
According to Natilus, Kona has received 400 orders and a full-scale model will be built and flown within the next two years. Much of the technology will then transfer to Horizon, which will have a regular cockpit and crew and, according to Matyushev, will enter service by 2030 — a hugely ambitious target, as it would be unprecedented for a brand-new aircraft to go from design to full certification in just six years.
“One of the challenges with the blended wing body design is stability and control,” he explains. “I think that’s where McDonnell Douglas and Boeing really stumbled — how do you stabilize the airplane?”
He says one way to achieve stabilization is via complex flight control systems — essentially computers, which Matyushev points out have caused problems with the Boeing 737 Max.
The other option is aerodynamics, or the design of the plane’s surfaces, which is the route Natilus has chosen and also what differentiates it from JetZero, according to Matyushev.
The new shape comes with some crucial benefits. “There’s a 30% drag reduction, but at the same time, you’re actually able to lower the airplane’s weight to accommodate the same amount of passengers or cargo, which is very unique,” he says. “With a small airplane, you have smaller engines, which create less fuel burn. So when you put the two together, it starts to create a reduction (in emissions) per passenger seat by about 50%.”
The much larger fuselage, which no longer looks like a tube, opens up possibilities for different layouts on board. “We have about 30% more floor space than a traditional airplane,” Matyushev explains. “So what I think a lot of our customers are thinking about is an elevated passenger experience. Could you bring back the lounge? Are there other spaces in the airplane that you could carve out for those long flights?”
Not everything in Horizon will be brand new; for example, the plane will use existing engine technology, leaving no room for hydrogen or electric options. “There’s a running joke in aviation — never put a brand-new engine on a brand-new airplane. That’s too risky,” Matyushev says. For the same reason, Horizon is designed to fit wherever a Boeing 737 or Airbus A320 would fit, requiring no change in airport infrastructure.
Uncharted territory
According to Gary Crichlow, an aviation analyst at Aviation News Limited, a series of delivery failures that have left airlines waiting for new airplanes well into the 2030s has created a “window of opportunity” for a new entrant to disrupt the status quo.
“That window, however, is very tight,” he says. “A key selling point for operators is commonality in terms of flight crew qualification. The 737 Max and A320neo’s success has been due in no small part to their ability to be integrated easily into existing 737 and A320 operations respectively: flight crews require very little additional training to transition.”
However, teething problems are a feature in every new aircraft and with a new, untested manufacturer and a new, yet-to-be-proven design, that’s pretty much inevitable. “(Horizon) will have a completely different seating and cargo loading plan, and require completely different flight and cabin crew. Avoiding that operational headache, and supporting when it happens, reliably and at scale, is probably the biggest challenge that Natilus will face in convincing potential customers to buy the Horizon instead of holding out for a more traditional 737 Max or A320neo replacement.”
Crichlow also flags potential hurdles in the plane’s path to certification with the aviation authorities. “The challenge for any clean-sheet design has always been the tremendous upfront cost to develop and certify it. In terms of certification, conventional aircraft such as the 737 Max 7 and 10, the 777-X, the A321neo XLR and COMAC C919 have all faced, and in some cases are still facing, significant regulatory delays to their manufacturers’ original timelines. With a design as different as the blended wing body, I’d expect regulators to be even more cautious.”
Matyushev is aware that Natilus is entering uncharted territory: “There’s a lot of questions about how you build a blended body at full scale, because all we have is wind tunnel data right now and then scale prototypes, but nobody’s actually built one at full scale,” he says.
With Natilus currently working on a full-scale prototype, some of those questions may soon be answered.