<hi style=afpcap>Several controversial designs have subsequently proved their value, including the F-111 which began life as a joint Air Force and Navy requirement to replace the F-4 Phantom. The Navy did not proceed with the project, although the Air Force elected to continue despite a vast increase in development and purchase costs. Four versions were ordered for the fighter bomber role, while a redesign produced the FB-111A as a long range strategic bomber for Strategic Air Command. Approximately half the F-111s served with Tactical Air Command in the USA, while the remainder were assigned to USAFE being stationed in England. The last of these was finally withdrawn in 1993. Depicted is the prototype F-111A during an early test flight from Fort Worth, Texas. </hi>
