What 5th generation USAF tactical fighter built by Lockheed Martin and Boeing will remain in service alongside the new sixth generation fighter?
Sixth-generation jet fighter:  The USAF is pursuing development and acquisition of a sixth-generation fighter through the F-X program to complement existing platforms in service such as the Lockheed Martin F-22 Raptor. Lockheed Martin F-22 Raptor: The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF).
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