 The USAF also needed to replace its F-105 Thunderchief and F-4 Phantom II fighter-bombers.The U.S. Congress sought greater commonality in fighter procurements by the Air Force and Navy, and in August 1974 redirected Navy funds to a new Navy Air Combat Fighter (NACF) program that would be a navalized fighter-bomber variant of the LWF.The four NATO allies had formed the "Multinational Fighter Program Group" (MFPG) and pressed for a U.S. decision by December 1974; thus, the USAF accelerated testing.