Secondly, while the USAF was not particularly interested in a complementary air superiority fighter competing with F-X, it did need to begin replacing its F-4 and Republic F-105 Thunderchief fighter-bombers. In April 1974, U.S. Secretary of Defense James R. Schlesinger announced that the LWF program would be redirected to a multirole fighter design in the new Air Combat Fighter (ACF) competition. ACF would not be a pure fighter, but more of a fighter-bomber, which essentially ended opposition from the F-X group.