The U.S. Air Force has not abandoned its program to build an advanced next-generation fighter , but it does need a redesign to get costs under control and better integrate its planned drone wingmen, the service’s secretary told Defense News in an exclusive interview.

Secretary Frank Kendall also said a revamped Next Generation Air Dominance fighter platform could end up with a less complex, smaller engine than originally intended to try to hold down its price.

“The family of systems concept of Next Generation Air Dominance is alive and well,” Kendall said June 28. “I can tell you that we are looking at the NGAD platform design concept to see if it’s the right concept or not. … We’re looking at whether we can do something that’s less expensive and do some trade-offs there.”

NGAD is intended to replace the F-22 Raptor fighter fleet in the 2030s. It is a highly classified program featuring a crewed sixth-generation fighter with adaptive engines that can switch to the most efficient configuration as flying conditions change. The effort also calls for autonomous drone wingmen — known as collaborative combat aircraft, or CCA — and other new systems such as cutting-edge sensors, weaponry, and technology that improves the jet’s ability to connect with satellites and other aircraft.

Top Air Force officials have repeatedly stressed such a network, including aircraft beyond the capabilities of fifth-generation F-35 jets, will be necessary to win wars.

“It is crystal clear to us that in order to get into the early to mid-[20]30s with a force that can win, we have to get to a sixth-gen fighter, and that’s NGAD,” retiring Lt. Gen. Richard Moore , who was the Air Force’s deputy chief of staff for plans and programs, said in April 2023.

But the price tag for such a system has long been a looming stumbling block, and rumors have swirled in recent weeks that NGAD might be endangered as the cash-strapped Air Force draws up its fiscal 2026 budget. The Air Force is now in the process of modernizing two expensive legs of its nuclear triad, even as it faces rising personnel costs and deals with the fallout from the Fiscal Responsibility Act’s budget caps for FY25.

At an Air and Space Forces Association event in June, Air Force Chief of Staff Gen. David Allvin hedged when asked whether the service can proceed with NGAD given its tight budgets. He later told reporters the service is still considering which way to go with the program.

Kendall also told Aviation Week that the service is having to reconsider its spending plans for FY26 as competing priorities mount up, and that it must identify the mix of systems necessary to provide dominant air power.

In his interview with Defense News at the Pentagon, Kendall said NGAD is now expected to cost roughly three times as much as an individual F-35 Joint Strike Fighter. With F-35s costing about $80 million to $100 million, that means NGAD’s price tag could be verging on $300 million apiece — and would greatly limit the size of its potential fleet.

“It’s a very expensive platform,” Kendall said. “It’s three times, roughly, the cost of an F-35, and we can only afford it in small numbers.”

When asked what target cost he wants for NGAD, Kendall said the Air Force isn’t far enough along to set such a goal — but added with a chuckle: “Ideally, I’d like to get it down to less than an F-35, or at least in the ballpark of an F-35. F-35s, as you know, are not cheap airplanes.”

Kendall reiterated that the Air Force will build a next-generation crewed fighter platform, and said he believes it will be based on the technologies developed for the Aerospace Innovation Initiative. That initiative was a strategy — which Kendall kicked off in his previous role as the Pentagon’s acquisition chief, and the Defense Advanced Research Projects Agency initially led alongside the Air Force and Navy — to develop prototype X-planes and a next-generation engine that ultimately led to the current NGAD effort.

However, Kendall said, “the design concept that came out of that [initiative] is a very expensive concept. Scale matters, numbers matter, and so does time. We want to get something there quickly.”

Along with looking for ways to bring down costs, Kendall said the Air Force wants to ensure NGAD can take full advantage of CCAs as it is redesigned. He noted the CCA concept came along after the service had begun working to develop NGAD.

“Having something that’s optimized to work with CCAs is another consideration as we look at NGAD,” Kendall said.

A smaller, cheaper engine?

The Air Force is also looking at NGAD’s cutting-edge propulsion system — a so-called adaptive engine — as it reconsiders its future fighter concept, Kendall said.

Clint Hinote, a retired three-star general and former deputy chief of staff for strategy, integration and requirements in the Air Force, told Defense News on June 21 that the Next-Generation Adaptive Propulsion program was quite expensive and could be driving up NGAD’s overall costs.

“The last numbers I saw on NGAP [Next Generation Adaptive Propulsion] were pretty high,” said Hinote, who was previously in charge of the Air Force Futures organization. “I do think that’s a factor. I don’t know if that’s the only factor, or the factor that’s really contributing to this decision. But it is true that the NGAP program, the development of an adaptive engine for the NGAD, was very costly.”

When asked if the propulsion system’s cost is making it harder for the Air Force to afford NGAD, Kendall replied: “What we’re looking for there is the most cost-effective propulsion system for the platform.”

The Air Force still wants to use the engine technologies it developed to give NGAD more range and fuel efficiency, he said. But as it seeks to bring costs down for NGAD, he noted, “the way you do that is if you can reduce the complexity, but also the size of the engine.”

While the engine and other systems intended for NGAD represented a technological leap forward, Hinote said, it was not out of reach from what he saw before he retired last year.

“We were making really good headway,” Hinote said. “High-pass engines, sensors — all that was coming together, I thought, pretty well.”

The adaptive engine technology that would be the foundation of NGAP is “revolutionary,” Hinote added.

General Electric Aerospace as well as Pratt & Whitney have each developed their own versions of an adaptive engine. The engine’s ability to shift its configuration to best respond to any given situation would be a major advancement in propulsion technology, Hinote said.

“If the [airplane’s] need is efficient cruise at high altitude, then [the adaptive engine would shift to a configuration] that looks a lot like a high-bypass engine, not all that dissimilar from the engines you’re seeing on the bottom of Airbus and Boeing airliners right now,” Hinote said.

High-bypass engines on aircraft such as 737s have large inlets that allow a great deal of air to pass through, he explained, which makes them very efficient. It’s not feasible to put an engine with such a large inlet on a fighter, but Hinote said adaptive engines can produce the same performance characteristics as a high-bypass engine at cruising speeds and altitudes.

And when a pilot needs to hit the afterburner and go to supersonic speeds, he added, “then you crank the engine down, you change the geometry of the winglets, and now you have a totally different engine that adapts to the demand given by the pilot.”

But those capabilities don’t come cheap. The cost of an adaptive engine was one of the factors that thwarted the Air Force’s desire to put it in the F-35, along with its incompatibility with the Marine Corps’ vertical-landing version and possibly the Navy’s carrier-based variant.

When asked about the potentially high cost for NGAP, Pratt & Whitney told Defense News it is working with the Air Force to use a collaborative digital design to drive down costs.

“We have already seen improved efficiency and effectiveness, resulting in cost and time saving thanks to digital collaborative work environments,” Peter Sommerkorn, the company’s executive director of sixth-generation programs, said in the statement.

Sommerkorn added that upgrades to the firm’s ceramic matrix composites facility in Carlsbad, California, as well as its turbine airfoil factory in Asheville, North Carolina, will save money on current and future propulsion programs.

GE Aerospace referred Defense News’ inquiries to the Air Force.

Kendall highlighted an op-ed one of his predecessors as secretary, Deborah Lee James, published in Defense News arguing NGAD is too important to kill for budgetary reasons, and said he is in almost total agreement with her.

In the op-ed, James wrote the Air Force must “explore alternative design and acquisition strategies” to get NGAD’s costs down and speed up its delivery. She said Congress and the Pentagon need to provide the Air Force enough funds for all of its major programs, and that the service should look to “innovative design and acquisition strategies” such as building less expensive fighters that can be more quickly made and regularly updated.

The Air Force hopes to spend more than $2.7 billion on research and development for NGAD in FY25, with another $557 million slated for CCAs. The service projects its R&D spending on NGAD to steadily rise in the years to come, reaching more than $8.8 billion in FY29, alongside $3.1 billion in CCA spending.

The Air Force has repeatedly sought to retire about 32 older Block 20 F-22A Raptor fighters — which the service says would cost too much to make combat-capable — to free up billions of dollars for NGAD. Moore said in 2023 that mothballing those F-22s would save about $2.5 billion over five years.

But Congress last year rejected the Air Force’s F-22 retirement proposal and appears poised to again stymie those plans in the FY25 budget.

The Air Force took a major step forward on NGAD in May 2023 when it sent industry a classified solicitation for the program’s engineering and manufacturing development contract. Northrop Grumman has ruled out competing for NGAD as a prime contractor, leaving Lockheed Martin and Boeing the likely two remaining contenders.

The Air Force last year said it intended to award that contract in 2024.

When asked if that contract is still coming this year, Kendall said: “I’m not ready to talk about any specific changes yet.”

Courtney Albon contributed to this report.