The Air Force made the final choice of Boeing over Lockheed Martin in the Next-Generation Air Dominance competition, and it was based on “best overall value,” a service spokesperson told Air & Space Forces Magazine.

The winners of some previous competitions for major programs have been decided by higher-level Pentagon officials, such as the Undersecretary of Defense for Acquisition, Technology, and Logistics. But the spokesperson said the Air Force’s acting senior acquisition executive, Darlene J. Costello, approved the NGAD pick, made by an unnamed leader of the evaluation team. There had been speculation that Secretary of Defense Pete Hegseth or even President Donald Trump would personally select the NGAD winner.

“The Milestone Decision Authority for the NGAD program is the Air Force Senior Acquisition Executive [Costello], who made the decision to proceed with Milestone B,” the spokesperson said. “As a matter of course, we do not reveal the identity of the source selection authority (SSA) in order to protect the integrity of the source selection process. This allows the SSA to operate free of any influence by outside parties and to provide an unbiased decision on the evaluation of the offerors solely based on the criteria set forth in the solicitation.”

Boeing’s proposal, now called the F-47, won because it “represents the best overall value to the government and is best suited to fulfill the Air Force’s requirements,” the spokesperson said. That stands in contrast to other contracts that have been awarded based on “lowest price/technically acceptable,” which is the criteria used when proposals are so evenly matched that cost becomes the key discriminator. A “best overall value” offeror may sometimes have quoted a higher price and was chosen because the source selection authority deemed the proposal more realistic, or if more value was added in the form of far better technical performance, lower-cost maintainability, or other factors.

The Air Force has not revealed the criteria used to judge the two entrants, and the spokesperson said the service “will not release additional details relative to the proposal.”

Industry sources told Air & Space Forces Magazine that past performance was not heavily weighted in the selection and counted for less than 10 percent of the scoring.

Boeing has struggled on current Air Force programs for the KC-46 tanker, T-7 trainer, and Air Force One presidential transport, incurring years of delays and about $10 billion of losses. Lockheed has had issues with delayed F-35 deliveries and stubbornly high operating costs.

Former government officials said Lockheed’s issues were a negative, but perhaps not as much as Boeing’s well-publicized management struggles.

The Air Force said it awarded Boeing a “cost-plus incentive fee contract” for NGAD engineering and manufacturing development, but the contract’s value and details are being withheld due to classification. The Air Force said the EMD contract includes “maturing and testing all aspects of the F-47,” and that this phase “will produce a small number of test aircraft for evaluation.” It also includes “competitively priced options for low-rate initial production.”

Boeing had previously won Air Force contracts with fixed-price offerings, only to eat major losses down the line. As a result, corporate leaders have said they will not bid for fixed-price contracts when it pertains to developing new technology.

Under cost-plus agreements, the government will typically cover overages resulting from maturing new technologies, but Boeing will be able to win additional funds if it meets or beats schedule, technical or cost requirements.

Neither the Air Force nor Lockheed Martin would divulge when that company will receive a debrief as to why it was not selected for the contract. Once that happens, though, Lockheed may file a protest if it feels the Air Force did not judge the proposals fairly or gave inordinate weight to certain factors. If it files a protest, the Government Accountability Office has 100 days in which to resolve the issues and decide whether the selection was made fairly.

“We expect the GAO to take the amount of time needed to thoroughly evaluate the record and provide an assessment,” the Air Force spokesperson said.

Major aircraft program awards are frequently protested, because the relatively low cost of a protest could result in billions of dollars in recovered work. Boeing and Lockheed, which teamed up in the 2015 Long-Range Strike Bomber competition, protested Northrop Grumman’s selection, but the GAO upheld that award and Northrop went on to develop the B-21.

However, Boeing succeeded in protesting the award of the KC-X tanker to a team of Northrop and Airbus in 2008, arguing the Air Force didn’t follow its own rules in assessing the entrants. The award was thrown out, the competition was re-run, and in 2011, Boeing won and is now building the KC-46.

When former Air Force Secretary Frank Kendall held off choosing an NGAD winner late in 2024—handing off the choice to the new administration—the Air Force awarded both Boeing and Lockheed technology maturation and risk reduction contracts of an undisclosed amount to keep their design teams together until the program’s future was resolved, or at least until the end of fiscal 2025. The Air Force declined to provide any details about the value of those contracts or what their deliverables might be.

“Contract timelines, costs, and capability deliveries are protected by enhanced security measures,” the service spokesperson said. “No further details are available.”

The Air Force said the competition for an engine that will power the NGAD fighter is a separate contest unaffected by the selection of Boeing.

The Next-Generation Adaptive Propulsion (NGAP) engine for the sixth-gen fighter “is platform agnostic,” the Air Force said, “and designs can be tailored to an extent for future fighter and other aircraft operating across various mission threads.” It did not specify what other platforms might be able to use the NGAP engine, but the only new designs on the horizon are the Next-Generation Aerial refueling System (NGAS) and later iterations of the autonomous Collaborative Combat Aircraft.

General Electric, with the XA-102, and RTX’s Pratt & Whitney, with the XA-103, are the competitors for the NGAP program. They both recently received contracts to build and test prototypes.

The Air Force declined to provide the designations or nomenclature for the X-planes it revealed that Boeing and Lockheed flew in the technology demonstration phase of the NGAD program, saying they remain classified.

However, while Boeing’s aircraft is now called the F-47, its X-plane predecessor wasn’t the X-47 or Y-47—the service said Chief of Staff Gen. David Allvin himself chose the designation.

The Air Force has a policy governing the designation and naming of aircraft and weapons, with new systems generally going in numerical order. The policy does, however, grant leaders discretion to skip design numbers.

The F-35 was an out-of-sequence selection. Had the Air Force decided to keep going in order from there, the NGAD fighter would have been the F-36 or F-37. Had the service decided to go back to its original sequence, it wold have been F-24 or F-25, following the Lockheed YF-22 and Northrop YF-23 which competed in the Advanced Tactical Fighter Competition.

The B-21 bomber likewise was supposed to carry the nomenclature B-3, but former Air Force Secretary Deborah James opted to name it the B-21 to emphasize that it is a “21st century bomber.”

The spokesperson said Allvin chose F-47 “in consultation with the Secretary of Defense” and the nomenclature “carries multiple significant meanings. It honors the legacy of the P-47, whose contributions to air superiority during World War II remain historic.” It also “pays tribute to the founding year of the Air Force” and recognizes Trump and “the 47th President’s pivotal support for development of the world’s first sixth-generation fighter.” Honorifics have usually been applied to the nickname for an aircraft, not its nomenclature.