The U.S. Defense Department’s Defense Innovation Unit (DIU) confirms it is considering two bids for a full-scale blended wing body (BWB) multirole demonstrator for evaluation as a potential future U.S. Air Force tanker and airlifter.
Disclosing new details of the initiative, Roberto Guerrero, deputy assistant secretary of the Air Force for operational energy, says, “right now we’re looking at a couple of designs. We’re going to downselect from those designs to one, and we see benefits in both air refueling at range where you can get much more productivity—much more fuel delivered—as well as cargo.”
Guerrero’s remarks came during a July 12 presentation at the Global Air and Space Chiefs Conference in London.
A planned downselect announcement is expected in about three weeks for the program, which will include the digital design of a prototype in the run-up to the manufacture of a prototype large-scale aircraft for certification and testing. At least one bidder is California-based startup JetZero, which has teamed with Northrop Grumman to propose a new BWB concept, details of which were first publicly disclosed in April by Aviation Week.
Although Boeing and Lockheed Martin have both previously studied non-tube-and-wing configurations for future airlifters and tankers, neither company is thought to have made a bid for the contest, proposals for which were first invited in July 2022.
Discussing specific targets of the DIU BWB design project, Guerrero says the prototype will be aimed at demonstrating at least a 30%-plus improvement in fuel efficiency compared to the Pratt & Whitney PW4000-powered Boeing KC-46, and a 30% increase in range. The project also targets a 70% increase in productivity compared to the C-17.
For the tanker-specific role, Guerrero says the increase in fuel efficiency would equate to a 94% increase in offload capability at a mission radius of 2,500 nm, or a 97% increase in mission radius with a 50,000-lb. fuel offload. The improved capability would also offer the Air Force the ability to refuel up to seven F-35s—as opposed to one aircraft—at a 4,000-nm radius, he adds.
“The cargo airplanes that we have right now are very good, but they could be a lot better when you start taking away the tube-and-wing designs and start looking at a more blended wing-type design,” Guerrero says.
The selected demonstrator could become a candidate for the Next Generation Air-Refueling System (NGAS), Guerrero told Aerospace DAILY on the sidelines of the conference. But the blended-wing technology remains unproven in the air refueling and military transport role, so the demonstrator is not formally part of the NGAS program at the moment, Guerrero adds.