In the quest to conjure the next generation of commercial airliners, U.S. start-up JetZero believes it could give Boeing and Airbus a run for their money. The California-based company is poised to shake up the commercial airline market with a novel type of airplane that hardly resembles any aircraft in service today.
Meet the Z4, a blended-wing-body (BWB) aircraft with a highly aerodynamic and lightweight airframe that JetZero says will deliver up to a 50% reduction in fuel burn and greenhouse gas emissions compared with traditional tube-and-wing airplanes that are currently in service, even while using the same conventional engines. The company has purposefully eschewed options for electric propulsion, including hybrid and hydrogen-based powertrains, on the grounds that these would slow certification and impose performance compromises.
JetZero’s first full-scale technology demonstrator, expected to make its first flight in 2027, will run on a pair of Pratt & Whitney PW2040 high-bypass turbofan engines, but it has not yet pinned down a supplier for the production version of the aircraft. Collins Aerospace, a Pratt & Whitney sister company under RTX, has agreed to provide the engine nacelles for the demonstrator. JetZero is developing the demonstrator aircraft with backing from NASA and the U.S. Air Force.
Closing the Mid-Market Gap
With a range of 5,000 nm and capacity for 200 to 250 passengers, the Z4 fills a gap in the market between large narrowbodies and small widebodies—a gap both Boeing and Airbus have sought to fill by introducing longer variants of existing single-aisle aircraft.
JetZero says its aircraft could offer a future replacement for some of Boeing’s larger 737 variants and out-of-production 757 and 767 models, as well as Airbus’s A320 family, particularly the A321neo. It first announced its plans at the Paris Air Show in 2023 and in recent months major carriers United and Delta have both announced backing for the program.
“This is kind of the New York to L.A. plane…but imagine if that same plane could also do transatlantic [flights] no problem, middle of America to the middle of Europe. That’s this plane,” JetZero chief product officer Scott Savian told reporters last month during a briefing at the company’s Long Beach, California headquarters, where a full-scale mockup of the aircraft’s interior was on display in a hangar.
Reimagining the Cabin
While JetZero is reinventing the wheel with a new type of airframe, it is also seizing the opportunity to completely reimagine the cabin. “We're at the limits of the current geometry,” Savian said of the old tube-and-wing design. “As soon as we move into this airframe, then we open doors to an entirely new world, not only in efficiency.”
Savian explained that the BWB concept “completely changes the way the cabin, the experience, the operations of an airline work.” For example, the layout with six cabin bays and an extra large door will streamline the boarding process. When stepping aboard, “you immediately go left, right, or center—no blocking up, no queues. Every single cabin you have direct access to. So, if you're lucky enough to be in business class, you don't have to watch 250 people go through the plane after you.”
Whereas most long-haul airplanes take at least 90 minutes to turn around between flights, JetZero’s streamlined cabin layout will reduce that time down to about 30 minutes, according to Savian.
Passengers will no longer have to walk through the galley when boarding, and flight attendants may appreciate the somewhat secluded and spacious central galley—located far away from the lavatories. “We’re not going to prepare your meal next to the toilet anymore,” he said.
The lavatories are all designed to be spacious and handicap-accessible as a standard feature, and they are located outside the cabin bays. “If you're in one of those seats near a lav, you will not have people queuing up from the lavatory next to the entire flight,” Savian remarked.
The improved passenger experience combined with the reduced fuel consumption and operating cost of the Z4 has garnered attention from airlines including United, Delta, and EasyJet. In April, United announced an order for up to 200 Z4 aircraft.
As the aviation industry works toward its collective goal of net-zero carbon emissions by 2050, much of the engineering focus has surrounded alternative fuel sources and novel propulsion technologies like electric, hybrid, or hydrogen powertrains. Rather than wait for new propulsion technologies to get certified and enter service to begin decarbonizing, JetZero is taking advantage of existing technologies as it works to commercialize a concept that dates back to the 1920s.
NASA Roots
JetZero traces its origins to a joint NASA-McDonnell Douglas BWB program in the 1990s that was led by JetZero co-founder and chief technology officer Mark Page. That program culminated in the successful flight of a 17-foot-long BWB demonstrator in 1997. After that, NASA continued to invest in BWB research and test BWB demonstrators, including the Boeing X-48, but no commercial programs ever emerged from all that work—until now.
“What a phenomenal thing to be able to start a company on the back of a billion dollars in research across decades with the world's experts,” JetZero co-founder and CEO Tom O’Leary said during the briefing in May.
O’Leary and Page founded JetZero in 2021 after working together on Beta Technologies’ Alia electric airplane and eVTOL program. The company went public in 2023, the same year it won a $235 million U.S. Air Force contract to design, build, and fly the full-scale BWB technology demonstrator by 2027 in partnership with Northrop Grumman and Scaled Composites. The Pentagon is considering JetZero’s BWB concept as a contender for its requirements for a new airlifter and air-to-air refueling platform.
However, O’Leary stressed, the Z4 demonstrator is not intended for an assessment of its potential for military applications. “It’s a commercial aircraft demonstration; there are zero military requirements,” he said. “The only requirement that the Air Force asked us to work on was L over D—lift over drag—just demonstrate the airframe and bring it to commercial production, because once that happens, then the Air Force and other military operations could really just deploy it as a derivative, which is similar to what’s done right now.”
Critical Design Review Complete
A JetZero spokesperson told AIN that the company completed the critical design review for the Z4 aircraft on May 29. JetZero chief technology officer Florentina Viscotchi noted that the company is now in the process of building an “iron bird” test rig. It has already completed testing on a wing test article built by Scaled Composites. The tooling has already been completed, and the fuel tanks are ready to be installed in the aircraft, she added.
Inside JetZero’s hangar at Long Beach Airport are two types of simulators for the Z4 aircraft: the flying qualities laboratory (FQL) and the integrated test facility (ITF). Whereas the FQL is being used to refine the flight control laws and software, the ITF is used to test hardware, including the flight computer.
“We'll be using the FQL to develop the actual handling qualities of the airplane, but then coming [to the ITF] to see how it all fits together, interfacing the actual hardware we're going to be using,” explained JetZero test pilot Matthew Stannard.
Although certifying this novel BWB aircraft will be no “cake walk,” JetZero believes the path to certification is pretty clear-cut, explained Bethany Davis, the company’s head of aircraft systems.”Certification will be what makes JetZero successful. It is the enabler of the future that we all want to see with this airplane,” she said.
JetZero intends to certify the Z4 under the FAA’s Part 25 rules for transport category airplanes. All of the hardware the company has selected to integrate on the aircraft already flies on Part 25 airplanes, which helps to derisk the process. The aircraft will operate just like any other Part 25 airplane, flying at the same altitude and speed and utilizing the exact same ground infrastructure.
To help with certification efforts, the company has also assembled an all-star team of certification experts, including former FAA administrator Steve Dickson and Lirio Liu, who served as the executive director for the FAA’s aircraft certification service. The company has also brought in dozens of experts with decades of experience from major aerospace companies like Boeing, Airbus, Gulfstream, and Bombardier.
JetZero is not the only company working on BWB aircraft. Canadian business jet manufacturer Bombardier is developing a smaller BWB aircraft—about the size of a Global 6000—with its EcoJet program, which has already flown two subscale demonstrators. Meanwhile, drone developer Natilus is working to introduce an autonomous cargo aircraft with a BWB airframe and a hydrogen-electric propulsion system provided by ZeroAvia. Airbus has also floated the idea of introducing a hydrogen-powered BWB airliner in the 2030s as part of its ZeroE initiative.