New Leadership Reimagines U.S. Air Force Fighter Fleet Structure

A new, long-term vision for the U.S. Air Force fighter fleet has gradually come into focus, and, if Congress approves, the changes for the tactical aviation portfolio could be stark.

A sixth-generation fighter to be acquired in the next decade by the Next-Generation Air Dominance (NGAD) program will cost in the “hundreds of millions” each and enter service in the 2030s alongside a phalanx of uncrewed Collaborative Combat Aircraft with autonomous control systems, Air Force Secretary Frank Kendall told a House Armed Services Committee (HASC) panel on April 26.

• NGAD fighter to cost “hundreds of millions”
• F-15EX procurement shrinks to 80 fighters

Until then, the Air Force plans to nearly halve a Trump administration plan to buy at least 144 Boeing F-15EX fighters as a short-term replacement for more than 200 F-15C/Ds, cutting the procurement program off after ordering only 80 of the Eagle II fighters in fiscal 2024.

Although the Lockheed Martin F-35A is the only feasible alternative as an F-15C/D replacement in the near term, the Air Force instead aims to slash planned orders for the stealthy, single-engine fighter over the next two years by as many as 34 jets, then ramp up orders after F-15EX procurement is completed in fiscal 2024. The 33-year-old F-15E fleet, meanwhile, emerges from the fighter reshuffling unscathed.

Finally, the Air Force wants to offset cuts to other fighter fleets with major upgrades to the remaining aircraft.

Controversially, the Air Force plans to retire all Fairchild Republic A-10s over the next five years, along with the 33 Lockheed F-22s that are not equipped to fight in combat.

In exchange, the Air Force would like to invest money in major upgrades. More than 600 Lockheed F-16s would be upgraded to the Block 70/72 standard, including Northrop Grumman APG-83 active, electronically scanned array radars and the Northrop Grumman Next-Generation Electronic Warfare suite.

Meanwhile, the surviving fleet of nearly 150 F-22s also is in line for new equipment. Gen. Mark Kelly, the head of Air Combat Command, may have previewed some of the options in an April 27 tweet that celebrated the anniversary of the first F-22 public demonstration routine in 2007.

Kelly’s tweet included a concept image of an F-22 equipped with pods mounted on outboard wing pylons carrying apparent infrared search-and-track sensors, low-radar-cross-section fuel tanks and a next--generation air-to-air missile. The F-22 supposedly receives the first operational Lockheed AIM-260 Joint Advanced Tactical Missile this year, but Air Force officials said during the April 27 hearing that the long-range weapon remained in development.

All of this fleet reshuffling would result in a 16% reduction in fighter fleet capacity through fiscal 2027, cutting a 2,138-strong fleet now down to 1,792 jets over the next five years.

Air Force officials are seeking to finance new fighter capabilities such as NGAD and F-35 Block 4 by retiring aircraft in the short term. The strategy has usually been met with resistance by Congress. Indeed, the Air Force’s total aircraft inventory in fiscal 2022 comes out about even with the fiscal 2018 fleet, despite proposals to retire hundreds of aircraft over the five-year period.

At the same time, Kendall has proposed reengining the F-35. The Pratt & Whitney F135 is meeting specifications, but Block 4 electronic upgrades risk overwhelming the power and thermal management system. Pratt designed the 43,000-lb.-thrust engine to provide bleed air from the compressor to cool the onboard electronics. But the Block 3F electronics introduced in 2016 already demand twice the optimal 15 kW of bleed-air offtake. The Block 4 upgrades, which include a new core processor, will require a 47-kW offtake from the compressor.

The Air Force is debating whether to upgrade the F135 or shift to the product of the Advanced Engine Technology Development program. The candidates include the GE Aviation XA100 or Pratt XA101 turbofans, which feature adaptive controls for bypass flow that can offer at least a doubling of cooling capacity compared with the F135.

As the tactical aviation portfolio is being reshaped, Air Force leaders have slightly widened the public discussion on the highly secretive NGAD program.

The NGAD platform has been built on a technology demonstration program that started in 2015 under DARPA called the Aerospace Innovation Initiative, which built at least one flying demonstrator by 2020.

The description of the program has changed over time. Until 2018, prime contractors such as Boeing, Lockheed and Northrop Grumman showed off concepts of crewed, sixth-generation fighters, aircraft featuring highly stealthy profiles with no vertical control surfaces that are difficult to keep hidden from low-frequency radars.

But NGAD development appeared to be delayed after a comprehensive review began in 2018. Long-term budget planning documents in 2019 showed that the Air Force had deferred a planned step-up in spending in fiscal 2023 to about $3 billion per year from about $1.5-2 billion, which potentially signaled the launch of an engineering and manufacturing development phase.

As chief of staff of the Air Force in 2019 and 2020, Gen. (ret.) David Goldfein always refused to confirm whether a crewed “sixth-generation fighter” was still included in the NGAD family of systems. Instead, Goldfein said repeatedly that the NGAD program was developing five critical technologies that were not intended to come together on a single aircraft. The statement did not preclude the presence of a penetrating counter-air fighter at the center of the NGAD family, but it did not confirm it either.

New Air Force leadership, however, has dissolved any such ambiguity. In written testimony submitted to the HASC, a joint statement from Kendall and current Chief of Staff of the Air Force Gen. Charles Q. Brown, Jr., is explicit: “This family of systems will include a sixth-generation crewed platform as well as uncrewed combat aircraft and a cost-effective mix of sensors, weapons and communications systems.”

Kendall said he expects to be fielding the NGAD in the 2030s, but two lawmakers, Reps. Donald Norcross (D-N.J.) and Vicky Hartzler (R-Mo.), said they understood the program is delayed. In response to a question from Hartzler in a later April 27 HASC tactical air and land forces subcommittee hearing, Lt. Gen. David Nahom, the Air Force’s deputy chief of staff for plans and programs, said the schedule had not appreciably changed and the program was on a good track.

A clue about the NGAD development schedule appears in the Air Force’s newly published five-year spending plan. The $1.36 billion step-up in funding now is planned in fiscal 2025, with a projected budget increase to $3.02 billion from planned spending of $1.66 billion in fiscal 2024.

The sixth-generation fighter at the heart of the NGAD program is already expected to become the most expensive tactical aircraft ever developed. The price of “hundreds of millions” each cited by Kendall aligns with a 2018 projection by the Congressional Budget Office, which estimated a unit cost of about $300 million each for a future penetrating counter-air platform.

With such a high price per copy, the Air Force is trying to shift to a different approach for its fighter fleet.

“We need a more affordable mix for the future, and the question is how we get there,” Kendall says. “And that’s one of the reasons I’m introducing the idea of uncrewed combat aircraft that are much less expensive and can be attritable.”

Meanwhile, Air Force planners are internally debating how future fighter squadrons will be composed with crewed and uncrewed elements. The newly branded Collaborative Combat Aircraft—formerly described as “Loyal Wingman”—builds on autonomous technology developed as part of programs such as Skyborg and Boeing’s MQ-28 Ghost Bat platform in Australia. It is “quite a few ways out,” Brown says.

Kendall has said he expects these aircraft to cost about half the price of the crewed platform, or potentially $150 million or more. In the short term, that is why the service is focusing on its four-aircraft mix of F-15s, F-16s, F-35s and the NGAD.