 The F-117 is primarily an attack aircraft, so its "F" designation is inconsistent with the DoD system.This is an inconsistency that has been repeatedly employed by the U.S. Air Force with several of its attack aircraft since the late 1950s, including the Republic F-105 Thunderchief and General Dynamics F-111 Aardvark.A televised documentary quoted project manager Alan Brown as saying that Robert J. Dixon, a four-star Air Force general who was the head of Tactical Air Command felt that the top-notch USAF fighter pilots required to fly the new aircraft were more easily attracted to an aircraft with an "F" designation for fighter, as opposed to a bomber ("B") or attack ("A") designation.