The U.S. Air Force would lose two squadrons of Boeing [BA] F-15C/D air superiority fighters if Congress enacts the service’s fiscal 2022 budget plan.

The Air Force plans to reduce its F-15C/Ds by 48 next fiscal year from 234 to 186. The latter is the same number of Lockheed Martin [LMT] F-22 stealth fighters that the service has.

The Air Force request could face particularly strong congressional headwinds, given that one of two possible replacements for the F-15C/D, the Boeing F-15EX, is not rolling off the production line in sufficient numbers to take up the slack. By the end of fiscal 2022, the Air Force budget says that it will have, as now, just two F-15EXs in service. The F-15EXs are in testing at Eglin AFB, Fla.

Plans had called for Oregon’s 173rd Fighter Wing, home of the Air Force’s F-15 schoolhouse, to be the first to convert to the F-15EX next year, while the 142nd Fighter Wing at Portland (Ore.) Air National Guard (ANG) Base would become the first operational F-15EX unit in 2023.

ANG F-15C/Ds are in Oregon, California, Louisiana, Massachusetts, and Florida.

Beside test and evaluation and weapons school squadrons, the Air Force has three active F-15C/D squadrons and six ANG squadrons. The active F-15C/D squadrons are the 44th and 67th Fighter Squadrons with the 18th Wing at Kadena Air Base, Japan and the 493rd Fighter Squadron with the 48th Fighter Wing at RAF Lakenheath in the United Kingdom. The ANG F-15C/D squadrons are the 104th Fighter Wing’s 131st Fighter Squadron at Barnes ANG Base, Mass.; the 125th Fighter Wing’s 159th Fighter Squadron at Jacksonville International Airport, Fla.; the 173rd Fighter Wing’s 114th Fighter Squadron at Kingsley ANG Base, Ore.; the 142nd Fighter Wing’s 123rd Fighter Squadron at Portland International Airport, Ore.; the 144th Fighter Wing’s 194th Fighter Squadron at Fresno ANG Base, Calif.; and the 159th Fighter Wing’s 122nd Fighter Squadron at Naval Air Station Joint Reserve Base New Orleans, La.

“We’re still working through those details” of how the proposed F-15C/D reduction will affect the number of F-15C/D squadrons and the number of F-15C/Ds per squadron, Air Force Capt. Jacob Bailey, a service spokesman, wrote in a June 1 email.

The service has frowned upon having mixed squadrons of legacy aircraft and newer planes due to what the service has said are increased sustainment costs for such squadrons.

The Lockheed Martin F-35A represents the other possible, near-term replacement for the retiring F-15C/Ds, but the Air Force is also planning to divest 47 older Lockheed Martin F-16C/Ds in fiscal 2022–a decision that, if enacted, would decrease the F-16C/D fleet from 936 to 889. The Air Force has always spoken of the single-engine F-35A as the replacement for the single engine F-16.

The inventory of F-35As would grow by 50 in fiscal 2022, from 326 to 376, per the Air Force budget request–an increase that would more than compensate for the loss of retiring F-16C/Ds.

Yet, ANG F-15C/D units have clamored for the F-35A.

“Guard leaders in the five F-15 states initially expressed a preference for the Lockheed-built F-35A,” the National Guard Association of the United States said last August. “The concern is, the F-15EX will be a predominantly Guard aircraft and may not receive the same attention as systems also flown in the active component.”

The Air Force wants to retire 201 fighter, tanker, transport, and intelligence, surveillance and reconnaissance aircraft in fiscal 2022 to save $1.4 billion to help pay for a requested research and development increase of $2.2 billion (Defense Daily, May 28).