Blended-Wing Body: Next Evolution in Commercial Aviation?

The most recent global market forecasts from Boeing and Airbus project demand for more than 43,000 new commercial aviation airplanes over the next two decades. But according to Aleksey Matyushev, co-founder and CEO of Natilus, the manufacturing titans may struggle to meet it.

Matyushev estimated that Boeing and Airbus have the capacity to produce about 11,000 and 15,000 planes, respectively, in that timeframe. That leaves a gap of more than 17,000—one the Natilus CEO believes could be filled by the company’s fuel-efficient, blended-wing body (BWB) design, Horizon.

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“I think the airlines are now more than ever interested in new ways of thinking, both from a manufacturing and a fuel efficiency perspective,” Matyushev told FLYING.

Horizon, which Matyushev said will have capacity for about 200 passengers, is one of a handful of regional jet concepts that developers position as solutions to airlines’ anticipated capacity crunch. Natilus claims it will burn 30 percent less fuel than traditional aircraft and slash emissions and operating costs in half.

Another BWB design, JetZero’s 250-passenger Z4, promises fuel burn reductions as high as 50 percent.

For now, these are simply promises.

Few BWB aircraft have advanced beyond the prototype and demonstration phase, and none have been developed to fly passengers. But major U.S. carriers such as United Airlines and Alaska Airlines—which have invested in and placed conditional orders with JetZero—are already exploring the technology.

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Delta Air Lines is even aiding JetZero’s development of the Z4, a prototype of which is expected to fly for the U.S. Air Force in 2027 under a $235 million contract award.

“Airlines need to refleet to more efficient aircraft and buy planes to support growth,” JetZero said. “Passenger demand is forecasted to double from 2019 levels by 2040, and the industry has pledged to net-zero carbon emissions by 2050. It will take innovation to meet this demand.”

From Flying Wing to Blended Wing

The BWB is an offshoot of the tailless, all-wing aircraft concept, or flying wing, which dates back to the early days of aviation.

In the 1910s, German engineer Hugo Junkers patented a pure flying wing design—a board-like airframe that would house engines and crew. The U.S. military used tailless biplanes for training around the time of World War I. Later flying wing designs, such as Northrop’s B-2A Spirit bomber, became well known.

It wasn’t until the 1990s that a BWB concept—which lies somewhere between the flying wing and traditional tube-and-wing—was studied in earnest.

In 1988, Dennis Bushnell of NASA’s Langley Research Center in Virginia posed a challenge to the industry: Develop revolutionary, rather than evolutionary, gains in the performance of long-range airplanes, such as the Boeing 747, McDonnell Douglas MD-11, or Airbus A320.

McDonnell Douglas accepted the challenge, sketching out an initial concept that promised to raise transport lift-to-drag (L/D) ratios from 17 to almost 28. That sparked NASA’s interest, and follow-on research predicted that the BWB configuration could achieve a cruise L/D ratio north of 27.

McDonnell Douglas, which later merged with Boeing, initially conceived an 800-passenger design.

“When Boeing and NASA first started looking at the configuration, they were really thinking long-haul, intercontinental,” Matyushev said.

However, that posed challenges, such as the pressurization of a massive, noncircular cabin. Engineers later scaled back to a 450-passenger concept, which served as the framework for the X-48B and X-48C—two 8.5 percent dynamically scaled test vehicles. The X-48B flew 92 times and the X-48C 30 times between 2007 and the latter’s retirement in 2013.

The X-48 test campaign proved that a BWB model could be produced and flown. Developers now believe the technology is nearing commercial readiness.

“Technology wise, we have figured out the majority of the challenges that were plaguing or were concerning NASA and Boeing in the late 1990s and early 2000s,” said Matyushev.

Modern Concepts

Today’s BWB concepts share a few similarities. Most lack a traditional tail and feature top-mounted engines akin to NASA and Lockheed Martin’s X-59, which is designed to reduce noise. Their vertical interior walls offer more cabin space than a typical configuration, which is billed as one of their key advantages.

Natilus’ Horizon is expected to raise interior capacity by 40 percent. That space also translates to the company’s Kona, an optionally piloted BWB cargo concept that was devised before the passenger variant. Matyushev said that makes Kona an ideal fit for regional air cargo.

“The densities of packages are incredibly low,” he said. “The traditional tube-and-wing configurations…cube out on volume before they top out on weight.”

Kona’s projected maximum takeoff weight (MTOW) of 19,000 pounds would place it near the FAA’s Part 23 limit, Matyushev said. He described it as a “lower-speed” model with a cruise speed of about 250 knots. The aircraft is unpressurized and designed specifically for cargo.

A possible “beachhead market,” Matyushev said, could be the cargo routes flown by carriers such as UPS and FedEx, which are about 200 to 300 miles.

Natilus aims to fly a full-scale, conforming Kona prototype—for which assembly is underway in San Diego—in the next two years or so. That was the company’s sole focus until about two years ago, when a “major U.S. airline” approached it about building a passenger model.

Horizon, Matyushev said, is built to replace single-aisle narrowbodies such as the Boeing 737, Max 8, and 10, and the Airbus A320neo. Per Boeing’s 20-year global forecast, single-aisle aircraft are expected to account for more than two-thirds of its more than 43,000 commercial deliveries.

Matyushev said the design and specifications of Horizon are still “morphing.” But he predicted it would fly at Mach 0.8 at about 41,000 feet. At its projected 160,000 pounds MTOW, Natilus is able to use flight-proven engines, including the Pratt & Whitney Geared Turbofan (GTF) and CFM International LEAP families.

“We thought about going higher and faster,” Matyushev said. “The engines are really centered around that design point, about Mach 0.8. [Otherwise] the maintenance costs go through the roof, even though the airplane is able to do faster missions and higher altitudes.”

The Natilus CEO believes certification under Part 25 won’t be challenging. But the company must prove Horizon’s capabilities, namely its handling and high-lift characteristics, through flight testing. Wind tunnel testing is planned for mid-2026, with market entry targeted in the early 2030s.

“Because we don’t have things such as a tail, it’s very tricky to design blended-wing bodies to stall correctly and then also make sure that their performance matches approach speeds and takeoff field performance” of similar aircraft, Matyushev said.

He said he was “excited” about the presence of competitors such as JetZero, which is designing a slightly larger BWB model on a similar timeframe. It plans to pour $4.7 billion into scaled production at its North Carolina manufacturing plant.

“There is no mid-market airplane in production today,” JetZero said. “Airlines need a plan for the 250-passenger/5,000 nm range to support their networks.”

According to the company, the Z4 will have wider-than-normal doors, 18-inch-wide seats, and “the most personal space of any aircraft.” It can be configured as a 2-by-3 or without middle seats to accommodate larger groups.

JetZero is working with Scaled Composites to build a full-scale demonstrator, with which it aims to prove the model’s other core advantage—a 30 percent improvement in L/D ratio. The Z4 will be certified under Part 25, with planned passenger transport, commercial freighter, and military refueling variants.

A handful of larger manufacturers are also developing BWB concepts. Airbus has explored a BWB model through its ZeroE program and developed an experimental prototype. Bombardier is studying the configuration under its EcoJet project.

Each of these developers will need to answer one big question.

Will It Work?

Other than larger interior size, the core advantage of the BWB is fuel reduction—and there is some evidence that it can deliver. The mid-2000s Silent Aircraft Initiative conducted by
Cambridge University and MIT researchers found that a 215-passenger BWB design showed a roughly 25 percent improvement in passenger miles flown per gallon of fuel, compared to existing commercial aircraft.

In the late 2000s, NASA and Boeing’s work on a pair of hybrid-wing body (HWB) concepts found a 25-29 percent reduction in fuel versus the Airbus A330-200FX freighter.

Later, researchers from Delft University of Technology found that 250- and 400-passenger BWB concepts had 12-23 percent higher aerodynamic efficiency than tube-and-wing aircraft designed under the same requirements.

However, these results fall short of the 30-50 percent reductions in fuel promised by Natilus and JetZero. There is also the question of passenger comfort. BWB models typically lack cabin windows due to structural concerns. Horizon has windows for only five rows of first-class seats.

Other questions remain, such as the aerodynamics of a BWB design far larger than those tested by NASA and Boeing. 

But with BWB developers earning the backing of United, Delta, and other airlines, engineers have what Matyushev called a “once-in-a-generation” opportunity to answer them.

This column first appeared in the January Issue 966 of the FLYING print edition.