Bigger Than a Cessna, Smaller Than a C-130: Air Force Funds Blended-Wing Body Concept

As the Air Force wrestles to solve the logistics of dispersed operations in the vast Indo-Pacific, it’s investing $3.5 million to help develop a new kind of aircraft: a blended-wing body freighter that’s smaller than a C-130 but larger than a Cessna for “sub-tactical” lift.

The startup firm behind the new aircraft, Natilus, thinks it could answer questions the Air Force faces about fuel, cargo space, and range to make its Agile Combat Employment concept work, an executive told Air & Space Forces Magazine.

The Pentagon’s Operational Energy-Innovation Directorate and the office of the Air Force’s assistant secretary for energy, installations, and environment funded the $3.5 million contract with Natilus, which will go toward development of the firm’s KONA aircraft, including “full-scale flight testing” starting in late 2027 or early 2028, Chief Operating Officer Nolan Giblin told Air & Space Forces Magazine in an interview. There is also a demonstration planned during a joint force exercise, likely in the Pacific.

Blended-wing body aircraft are halfway between the traditional tube-and-wing and the flying wing designs, with the wings and fuselage blending together to help create lift. Its shape makes it more aerodynamic and fuel efficient, while increasing the size of the cabin in the fuselage.

“When you couple the aerodynamic efficiency of about 30 percent reduction in fuel with the added volumetric capacity, it really boils down to moving more for less,” said Giblin.

In 2023, the Air Force launched a BWB demonstrator/prototype program with startup JetZero, who is partnering with Northrop Grumman. That aircraft, dubbed Z4, is expected to fly in 2027.

But while the Z4 is a large aircraft on par with a KC-46 or C-17, KONA is far more modest and meant for an entirely different use, Giblin said. JetZero has pitched the Z4 as a potential future aerial refueler for the Air Force, with a wingspan approaching 185 feet and a maximum operating weight of 362,000 pounds; Giblin said KONA is focused on smaller airlift and has a wingspan of 85 feet and a max takeoff weight of 19,000 pounds.

Still, the Air Force’s support for the Z4—the service has invested about $235 million in the project—encouraged Natilus that there are “tailwinds” for BWB aircraft in the Pentagon, Giblin said.

Originally, Natilus developed KONA for “short-haul cargo operations and e-commerce,” according to its website. Companies like FedEx, DHL, and Amazon rely on massive “hub-and-spoke” networks, and a small BWB aircraft could move loads to smaller spokes more efficiently compared to a larger, tube-and-wing airframe. Besides being more fuel efficient, a BWB aircraft’s shape provides more total volume in the cabin, Giblin noted.

“Today’s tube-and-wing aircraft that they’re flying at the spoke-level of the hub and spoke are [maxing] out on volume before they top out on weight, and so they’re literally leaving revenue on the ground every time they take off. And so there’s an interest for a more volume-centric platform” Giblin said of commercial firms.

The Air Force is looking to build its own hub-and-spoke model—agile combat employment calls for dispersing small teams of Airmen and aircraft from large hubs to remote or austere airfields to make it harder for adversaries to target them.

Ensuring those forces can move efficiently and are supplied at their new locations, however, is no small feat. That’s especially true in the Pacific, where the distances are vast and mostly covered by water. The Air Force has about 270 C-130 tactical airlifters, which can haul 40,000 pounds of cargo, but service officials have shown an interest in more flexible solutions.

That’s led industry to develop an onslaught of small cargo drones—some are Cessna 208s modified to fly autonomously, others are clean-sheet designs. They range in payload capacity from 500 pounds to a few thousand.

KONA is at the high end of that range, capable of carrying payloads up to a little more than 8,000 pounds with a range of 800 nautical miles. Its capacity in particular is greater than the modified Cessnas other firms are working on, filling what Giblin described as a “capability gap” between the light utility aircraft and the C-130.

Like the smaller Cessnas, though, KONA will be “optionally manned.” For commercial operations and inside the U.S. under the FAA’s jurisdiction, Giblin said, a human pilot will likely fly. But for the Air Force, autonomy is a key attribute, especially when flying in contested airspace.

“We do have our own homegrown [autonomy] software stack. However, we also have optionality to partner with folks that are already looking at this in a serious way,” Giblin said. “ … And so, we have a couple different paths towards achieving autonomous flight.”

Natilus is already building its demonstrator—the Air Force contract will accelerate that production. Giblin said the “vertical tails, flight control surfaces are already built, the cargo loading system was delivered by Raytheon a couple weeks ago, we just put on order used PT6 engines.” Still to come are the wing shipset and the fuselage.