Is it finally time for the blended wing body? JetZero thinks so, and the California-based startup has emerged from stealth mode to unveil a multi-mission design targeting the medium-sized commercial and military tanker transportation markets.
First appearing as a concept in the late 1980s and studied on and off since then, the blended wing body (BWB) has failed to gain traction despite promising performance projections. Now, JetZero says, a huge market gap for a viable midsize airliner and the U.S. Air Force’s simultaneous quest for a similarly sized advanced tanker transport means the stars are aligned for a BWB like never before. ‘Now.
- JetZero emerges to challenge Boeing and Airbus
- The full-scale Z-5 demonstrator is set up for flight tests
- The pin gear concept is key to the new blended wing body
The BWB concept combines airframe structure and aerodynamics to reduce weight and drag, while allowing the fuselage to contribute lift. Also known as a hybrid wing body, the configuration is usually tailless and is more efficient than a conventional tube-and-wing design due to its reduced wetted area, frictional drag, and lower drag. BWBs are also inherently quieter than current airliners because the airframe shields most of the noise from the topsurface-mounted engines.
JetZero’s Z-5 design, the first in a proposed family of Z-series aircraft, is optimized for a range of at least 5,000 nm and up to 250 passengers. The all-composite aircraft has a wide single deck and a high aspect ratio wing. While this extends the wingspan to nearly 200 feet, similar to an Airbus A330, the body length is less than that of a Boeing 767. Despite the overall size, JetZero says the mid-range aircraft will be about half weight and will require half the horsepower of the aircraft it replaces, such as the 767.
Importantly, for JetZero’s business plan, which calls for a 2030 entry into service, the reduced weight and power requirements are designed to allow the Z-5 to use existing single-aisle engine derivatives such as the CFM Leap 1 or Pratt & Whitney PW1100G. The aircraft features mostly conventional systems, simplifying development and reducing costs and risks, the company adds.
The Z-5 is aimed at the heart of the market for the new mid-range airplane (NMA) that was studied by Boeing until the project was shelved in 2020. Although Boeing has since resumed low-level studies of a conventionally configured NMA-class aircraft for possible service entry in the mid-1930s, the manufacturer, by its own admission, is still years away from launching a new product.
Airbus is also years away from developing an entirely new aircraft in the NMA category, although a 200-seat BWB is one of three mid-2030 hydrogen-powered concepts being studied as part of its ZEROe initiative. The European manufacturer is instead focusing on the development of the A321XLR, a long-range variant of the A321neo designed to carry up to 220 passengers on routes up to 4,700 nautical miles. The aircraft is expected to enter service in 2024.
But the program that could provide a near-term stepping stone for Z-5 development is the US Department of Defense’s plan for a BWB demonstrator to be evaluated as a future tanker and carrier aircraft. The initial goal is to develop the digital design of a prototype as well as perform initial airworthiness and test planning for a demonstrator, culminating in the production of a full-scale prototype aircraft for certification and testing, says the Air Force.
JetZero submitted its proposal for the $245 million cost-sharing program in late March, and with flight tests of a NASA-supported subscale demonstrator scheduled for this year, the company decided it was the right time to make his concept public.
The cornerstone is that, after completing the conceptual design, we need to move from the incubation phase to the demonstration phase, says JetZero co-founder Tom O’Leary. That conceptual design led to the development of a blended wing body that would fill the market average gap with existing single aisle engines and a 50% reduction in fuel burn and emissions and be a viable tanker.
The Air Force’s goal is to demonstrate the capability of a commercial BWB that can be converted [into a tanker], OLeary continues. We have letters of support from across the supply base that we sent with our Air Force proposal, including mission and fabrication systems.
Because of its fuel efficiency, the Z-5 can carry up to twice as much fuel as the Boeing KC-46 on a max-range mission, JetZero says. The aircraft is also designed to use the current airport infrastructure. The Air Force is expected to select a winning proposal by mid-year and expects to begin demonstration flights in 2027.
The Air Force released its initial solicitation last year, saying BWB is one of the single most impactful technology opportunities for future U.S. Air Force aircraft, both in terms of improving capabilities and reducing gas emissions. greenhouse. Converting the cargo, tanker and bomber fleets to a BWB project would reduce annual fuel costs by $1 billion compared to kerosene at current prices, he added.
The Z-5 emerges at a serendipitous moment for the industry, says Barry Eccleston, former CEO of Airbus Americas and International Aero Engines and JetZeros advisory board member. You have all these tailwinds from the environment and the Air Force and NASA, plus you have the tailwind of technology, which makes it doable when it wasn’t before, he says. So you contrast that with the fact that Boeing and Airbus aren’t doing anything new in this space and you say, “We can’t just sit here and do nothing.” The industry deserves it and the industry needs it. If you have something that you know is 30-50% better than today’s products, why wouldn’t you?
JetZero, meanwhile, is preparing to fly test its underscale BWB demonstrator, a 23-foot wingspan, 12.5 percent scale vehicle, funded under a 2021 contract awarded during an earlier round of the program. NASA Sustainable Flight Demonstrator (SFD). The aircraft will be used to evaluate the Z-series configuration, a key feature of which is a new landing gear design that maximizes internal volume and assists the aircraft in rotation. The SFD lead contract went to Boeing in January for development of a 737-sized demonstrator of the Transonic Truss-Braced Wing concept.
Developed by Mark Page, a BWB veteran since McDonnell Douglas and co-founder and chief technology officer of JetZero, the pin gear concept improves low-speed pitch control and lift capacity, two key challenges faced by BWB projects. First designed for the proposed Ascent 1000 BWB airliner by California-based Dzyne Technologies, a precursor to JetZero, the design moves the nose landing gear forward and main gear rearward into the unused interior volume a aft of the cabin.
For takeoff, the nose gear extends several feet to raise the angle of attack by about 6 degrees, allowing the BWB’s body to produce lift to amplify the effect of the aircraft’s elevons, JetZero says. The design, which is passively controlled without the need for pumps or actuators, allows the Z-5 to reach pitch attitude faster. This allows for a slower takeoff speed and reduces the requirement for high takeoff thrust. It also eliminates the need for high-lift staves on the leading edge and reduces the size of the trailing edge flaps.
To counter concerns about passenger egress, ride quality, and lack of windows in cabin sections, all criticisms of earlier BWB concepts, the Z-5 has side windows in the forward section and skylights in the main and aft cabins . While no interior dimensions have been released, the aircraft is expected to have a similar cabin width and ride quality to the Airbus A380. For the emergency exit, the Z-5 would follow the principles outlined for the Ascent 1000, which offered faster access to the fore and aft exits than a comparable conventional cabin layout.
JetZero says advances in composites for primary structures, added to the Z-5’s single-deck configuration, eliminate the design challenges of building pressure vessels in a non-circular fuselage. While the initial design is based on conventional tanks for sustainable aviation fuel, the company says the BWB configuration provides a large internal volume for future liquid hydrogen fuel tanks.
As part of its industry development plan, JetZero says it is simultaneously launching an outreach to private sources of funding and engaging with potential program partners. For the tanker demonstrator proposal, this includes Northrop Grumman, the only major airframe manufacturer with experience designing and manufacturing flying wing aircraft similar to the BWB configuration.
We think we’re in a really good position with the Air Force to win this award for the BWB demonstrator program, says OLeary, who was previously chief operating officer of electric vertical take-off and landing aircraft startup Beta Technologies. To build it, we have a number of industry partners. To come up with a conceptual design, we had to work with the entire supply base. So you name it, we talked to them. There’s no one who said, “Oh, that’s crazy, we’re not going to work with you.” And they’re all, from the top to the bottom of the supply base.
One of the biggest battles is, of course, that Boeing and Airbus are going to work really hard to make sure that doesn’t happen, Eccleston points out on the competitive aspect. I’m not saying we’re smart enough to outsmart Boeing and Airbus, but we’re getting a group of partners that will give us real credibility, he adds. So when the first question you get asked in the market is how are you going to do all of this? We have a plan and we have the strength of partners to make it happen.
