An F-15EX Eagle II from the 85th Test and Evaluation Squadron takes flight for the first time out of Eglin Air Force Base, Fla., April 26, 2021. (Savanah Bray/U.S. Air Force)

CAMP FOSTER, Okinawa – The Air Force is considering a plan to permanently replace its aging fleet of F-15 Eagle fighters on Okinawa with a smaller number of more advanced aircraft, a Japanese news magazine reported recently.

The Air Force informed lawmakers on Capitol Hill that it plans to permanently deploy 36 F-15EX Eagle II fighters at Kadena Air Base to replace the 48 F-15C/Ds previously stationed there, Nikkei Asia reported Monday, citing unnamed congressional sources briefed on the plan.

The multi-role F-15EX fighters, derived from the F-15E Strike Eagle, could be bolstered by unmanned drones.

Some lawmakers and scholars expressed concerns about the message a smaller permanent fighter presence would send to allies and potential adversaries in the region, the news magazine reported.

“I support a permanent basing of F-15EX aircraft at Kadena but am concerned about the Air Force’s initial plan to station only 36 new aircraft, replacing the 48 divested ones,” Rep. Rob Wittman, R-Va., told the outlet. Wittman, vice chair of the House Armed Services Committee, said he wants to see an “operational analysis” that supports the decision, Nikkei said.

 A representative for Wittman did not return calls and emails Monday from Stars and Stripes.

Zack Cooper, a senior fellow at the American Enterprise Institute, told Nikkei that the decrease will “raise some eyebrows.”

The Air Force is halfway through a two-year plan to replace Kadena’s 48 F-15C/D fighters of the 44th and 67th Fighter Squadrons with rotating squadrons of more modern aircraft, including the fifth-generation F-35A and F-15E Strike Eagles.

Some F-15s from Kadena went to Air National Guard units in the United States or to the Air Force boneyard at Davis-Monthan Air Force Base in Arizona.

The upgrade comes as tensions increase between the U.S. and China, a regional power the Pentagon has labeled an aggressive presence in the East and South China Seas and a global “pacing challenge,” according to the 2022 National Defense Strategy.

A spokeswoman for the Air Force declined to discuss the permanent deployment of fighters to Kadena.

“We continue to support the region with rotational fighters,” spokeswoman Ann Stefanek wrote by email Monday.

Jeffrey Hornung, a senior political scientist at Rand Corp., said having fewer fighters in one place is in line with the Air Force’s dispersal doctrine, agile combat employment. Agile combat employment calls for operations to shift from centralized air hubs to a network of smaller, dispersed sites or cluster bases.

Deploying fewer aircraft “is perhaps just them thinking, ‘OK, we will have access someplace in the region, whether that be Japan, Philippines, wherever,’” he told Stars and Stripes by phone Monday. “You don’t want to put everything back into Kadena.”

Toshiyuki Shikata, a former lieutenant general in the Ground Self-Defense Force, agreed.

“It is better to have improved aircraft than keeping the aircraft with inferior quality in larger quantity,” Shikata said by phone Tuesday. “I believe the replacement will take place in a way that keeps deterrence.”

Permanently deploying Eagle IIs, even in fewer numbers, would show a U.S. commitment to the defense of Japan, Junjiro Shida, an associate professor of international politics at Meio University on Okinawa, said by phone Tuesday.

“Japan and the U.S. are developing a structure to jointly operate,” he said.

The F-15EX, made by Boeing, arrived at Eglin Air Force Base, Fla., in March 2021. A two-seat aircraft operable by a single pilot, it comes with increased payload capacity and advanced avionics. It can carry hypersonic weapons designed to combat future near-peer adversaries.

higa.mari@stripes.com; Twitter: @MariHiga21