The United States Air Force has no interest in purchasing either Boeing’s advanced fourth-generation F-15X version of the aging Eagle. Nor does the service have any plans to revive the stealthy fifth-generation Lockheed Martin F-22 Raptor in either its original configuration or in a modified form with avionics from the Lockheed Martin F-35 Joint Strike Fighter. Instead the priority for the Air Force is to produce as many F-35s as it can to increase the proportion of fifth-generation fighters in its fleet while it continue to explore next-generation technologies for the future air superiority mission.
"We are currently 80 percent fourth-gen aircraft and 20 percent fifth generation aircraft,” Air Force Secretary Heather Wilson told Defense News’ Valerie Insinna in a Sept. 5 interview. "In any of the fights that we have been asked to plan for, more fifth gen aircraft make a huge difference, and we think that getting to 50-50 means not buying new fourth gen aircraft, it means continuing to increase the fifth generation.”