The U.S. Air Force’s fighter fleet is nearly 50 aircraft short of the number required by Congress, according to a recent Congressional Research Service report that outlines questions lawmakers face as the service plans its future fighter force.
The fighter fleet inventory currently falls short of the statutory requirement of 1,145 fighters, with 1,098 aircraft currently in the fleet. The service also operates an aging and “heavily used” fleet, with aircraft averaging 27.4 years old, according to the report. The authors highlighted that the fighter inventory may continue to decline until 2030 before it begins to grow again.
Although Congress has always reserved the authority to weigh in on the force’s fleet size and composition, issues with sustainment, personnel and training — identified by the service in a 2025 report to lawmakers — spurred different considerations on its fighter force structure to account for capabilities and readiness.
“USAF’s proposed fighter force structure plan raises potential issues for Congress regarding the size, capability, affordability, and feasibility of achieving planned inventory levels,” the report reads.
As the aircraft inventory was expected to fall below the mandated minimum, the Department of the Air Force’s 2025 report proposed using Combat-Coded Total Aircraft Inventory (CC TAI) rather than Primary Mission Aircraft Inventory (PMAI) to measure its fighter force. While PMAI only counts aircraft assigned to primary missions, CC TAI includes backup aircraft and attrition reserve aircraft.
The change would provide a broader accounting of the aircraft available to support combat operations.
The service reported that procuring aircraft in larger numbers could increase the inventory to 1,558 by fiscal 2035. This would also allow the force to divest older fighter aircraft and prioritize next-generation fighter and uncrewed aircraft development, as well as increase F-35 and F-15EX production.
However, annual sustainment costs have increased by around $950 million since fiscal 2019, with an annual shortfall of roughly $400 million in weapon system sustainment funding, per the report.
The proposal leaves Congress to consider whether to accept, reject or modify the Air Force’s proposed force structure, including how to respond to the proposed inventory-counting method, production and workforce constraints, and plans to modernize Air National Guard and Air Force Reserve units.
The report notes that increasing the number of aircraft does not necessarily increase combat capability if personnel and training capacity do not keep pace, raising questions about the feasibility of the service’s planned inventory levels.
The report also says Congress could consider lessons from the war in Iran, which could “potentially support or challenge the assumptions underlying the 2025 DAF report.”
The Congressional Research Service also identified questions about whether the Air Force can produce enough pilots and maintainers to support its planned fleet, how quickly it can retire older fighters, such as the F-22 and A-10, and how it should modernize fighter forces in the Air National Guard and Air Force Reserve.
Congress could also weigh the pace of moving aircraft into the reserve components and whether to pursue an upgraded F-16 for Guard units.
Cristina Stassis is a reporter covering stories surrounding the defense industry, national security, military/veteran affairs and more. She previously worked as an editorial fellow for Defense News in 2024 where she assisted the newsroom in breaking news across Sightline Media Group.