The Air Force’s proposed budget for fiscal 2025 would cut procurement of two major fighter programs — the F-35A and F-15EX Eagle II — and boost research and development funding for future capabilities.

The service plans to buy 42 Lockheed Martin-made F-35As for $5.9 billion and 18 Boeing F-15EXs for $1.8 billion next year. That would be a reduction from the 48 and 24 fighters, respectively, the service originally expected to buy.

The Air Force plans to stop buying F-15EXs all together after 2025 concludes, which will cap the entire line of Eagle IIs at 98 — six fewer than the 104 the service had been planning to buy. The Air Force’s expected total purchase of 1,763 F-35As remains unchanged.

The Air Force also wants to cut 250 aircraft in 2025, including 56 A-10 Warthogs, 65 older F-15 C and D Eagle fighters, 26 F-15E Strike Eagles with less-capable engines, 11 F-16 Fighting Falcons, and 32 Block 20 F-22A Raptors the service said would be prohibitively expensive to ready for combat. The service expects those retirements, if approved, would save more than $2 billion in fiscal 2025.

The Department of the Air Force’s fiscal 2025 proposed budget requests a total of $217.5 billion, an increase of $2.4 billion, or 1.1%, over its request from this year. Kristyn Jones, who is performing the duties of undersecretary of the Air Force, noted to reporters that the increase does not keep up with inflation.

The service asked for $188.1 billion, a $3 billion or 1.6% increase over its 2024 request. The Space Force’s requested $29.4 billion budget would be a 2% drop from the 2024 request.

Air Force Secretary Frank Kendall told reporters in a March 8 briefing the service “had to make some hard choices” to fit within the constraints of the Fiscal Responsibility Act.

The Fiscal Responsibility Act caps the government’s spending increases as part of a deal Congress struck last year to avoid a default on the nation’s debt. For the Defense Department, that limits its 2025 budget to $850 million, less than the $860 million the administration originally anticipated.

Kendall described the resulting budget as “acceptable,” and “essentially consistent” with the fiscal 2024 budget. But although he said it moves the department forward on key programs and strikes a balance between near-, mid- and long-term programs, he said he’d “like to be able to move faster.”

And more “tough choices” are ahead in fiscal 2026′s budget, he warned, including the first real effects of the LGM-35A Sentinel program’s severe cost overruns. The Air Force’s next intercontinental ballistic missile, slated to replace its aging Minuteman III nuclear missiles, has seen its costs ballon at least 37% and triggered a cost overrun process called a critical Nunn-McCurdy breach.

“Life gets a lot harder as you get past [20]25,” Kendall said.

The Air Force tried to strike a balance between mid-term procurement of more air frames and capabilities that have already been developed, and research and development of future advanced capabilities the service hopes will pay off in the long term.

“My priority is to get to a next generation of capabilities as quick as we can, because of what China’s doing in terms of their modernization,” Kendall said. He added later, “China is advancing very quickly, and they’re not stopping. So we really need, as a priority, to get to a next-generational capability. And you can’t even start to buy that until you’ve done the research and development.”

That resulted in a “tradeoff” in favor of R&D over procurement, Kendall said, to give future administrations options of new capabilities it can choose to buy as threats change.

Rep. Rob Wittman, R-Va., warned at the March 7 McAleese Defense Conference in Washington that Chinese President Xi Jinping is preparing to make a move on Taiwan by 2027. Wittman said military strategies that depend on fielding capabilities by about 2030 will come too late, and the U.S. military must field shorter-term capabilities to be able to dissuade China from trying to take Taiwan by force.

“Anybody that uses a metric and says, ‘We’ll get this stuff done by 2030′ — wrong answer,” Wittman said. “2027 needs to be the metric. That’s how we will have the opportunity to deter” China.

In a gaggle with reporters at McAleese, Kendall said the Air Force has to take a longer view, and will need to counter China not just in 2027, but for years to come.

“It’s a risk balance over time,” Kendall said. “If you fixate only on 2027, you’re going to find that in ‘29, you’re in big trouble. And ‘29 is going to come.”

Squeezing costs

A variety of rising costs are squeezing the Air Force’s budget, Jones said, and led to the procurement cuts. The department expects to spend about $1 billion more in 2025 to keep the number of flying hours and weapon system sustainment on par with 2024 levels, and personnel costs such as military pay and benefits are also going up, she said.

R&D funding for Sentinel would remain flat from the 2024 request at $3.7 billion. And the service wants to spend $700 million on six construction projects for Sentinel in 2025, as well as another $70 million for planning and design, a major increase from the $140 million it requested for Sentinel construction in 2024.

Jones said some of the changes included in the “reoptimization for great power competition” reorganization the Air Force unveiled last month will help set the Sentinel program back on track. Those changes would include putting a three-star general in charge of the Nuclear Weapons System Center, and having a two-star general serve as a program executive officer for ICBMs. Jones said the Air Force is still studying the program’s requirements and looking for alternative strategies that could save money.

Overall funding for the B-21 Raider stealth bomber will remain fairly steady, although some funds will shift from R&D to procurement as the bomber continues in its low-rate initial production phase. R&D funding for the bomber’s engineering, manufacturing and development phase would dip from $3 billion in 2024 to $2.7 billion in 2025, while procurement funding would increase from $2.3 billion to $2.7 billion.

The Next-Generation Air Dominance program, the service’s future fighter system, would receive an additional $815 million to develop and test its air vehicle, mission systems and capabilities, bringing spending on that program to more than $2.8 billion.

The Air Force’s collaborative combat aircraft, or CCA, program would receive $559 million in R&D funding to continue development, prototyping and integration of its air vehicle, which would be a $166 million boost over 2024 levels.

CCAs are drones outfitted with autonomous software that could fly alongside crewed NGAD and F-35 fighters into battle and carry out missions such as strikes, reconnaissance, and electronic warfare operations. The service now has contracts with five vendors on this program — Lockheed Martin, Boeing, Northrop Grumman, General Atomics and Anduril — and plans to winnow the field to two or three in the months to come.

The CCA program would also receive another $116 million to test its autonomous capabilities and for experimentation programs such as Project Venom and the experimental operations unit. And the service said its proposed 2025 funding for CCAs would allow it to lock down the aircraft’s design, build production-representative test aircraft for the program’s first increment, begin testing and refine the concept for its second increment.

The Air Force also plans to buy 15 KC-46A Pegasus tankers for $3.1 billion and seven T-7A Red Hawk trainers for $233 million. And it would retire 16 KC-135 Stratotankers as it brings on new KC-46s.

The service plans to retire 22 T-1A Texan II training aircraft to free up more resources that can be invested in newer pilot training technologies.

And the budget would provide $13.7 million for the Air Force’s tanker recapitalization effort to serve as a bridge between the current wave of KC-46s and the service’s planned Next-Generation Aerial Refueling System, or NGAS. That choice will likely be between more Boeing KC-46s and a tanker from Airbus. The service expects to finish its acquisition strategy for that tanker this summer, and then release a request for proposal in 2025. The Air Force plans to start requesting procurement funding for that tanker in 2027.

The Air Force started conducting an analysis of alternatives study for NGAS in January, Maj. Gen. Michael Greiner, the Air Force’s deputy assistant secretary for budget, told reporters. The service wants to spend about $7 million on preparing for NGAS, including conducting modeling and simulation studies, so it can field an advanced tanker by the mid-2030s.

The service also wants to boost its purchases of AIM-120 Advanced Medium Range Air-to-Air Missiles, or AMRAAMs, Long Range Anti-Ship Missiles, or LRASMs, and Advanced Anti-Radiation Guided Missile-Extended Range missiles, or AARGM-ERs. The LRASM and AARGM-ER purchases would increase considerably — from 27 in 2024 to 115 in 2025, and from 14 in 2024 to 128 in 2025, respectively.

Kendall said the Air Force is hoping to continue its strategy of multi-year procurement purchases for AMRAAM, LRASM, and the Joint Air-to-Surface Standoff Missile-Extended Range missile.