air superiority fighter, then launched a competition among aircraft manufacturers for the final design. In 1962, General Dynamics and Boeing were selected as finalists with the General Dynamics variable-geometry wing Tactical Fighter Experimental (TFX) design eventually winning out. Designated as the F-111, the Navy version was known as the F-111B and the USAF version the F-111A, with the first flight of the F-111A taking place in December 1964 and the first production models delivered to the USAF in 1967. Additional variants such as the FB-111A for SAC and the F-111E, F-111F and EF-111A for TAC and USAFE, plus the F-111K for the RAAF followed. Meanwhile, the Navy's F-111B program was canceled after five examples when it became apparent that its performance characteristics were unsuitable for an aircraft-carrier based fighter and interceptor, with many of its design features and systems being incorporated into the successful Grumman F-14 Tomcat. In all, 562 F-111s of all series were built. USAF also acquired a number of other USN aircraft originally designed for aircraft carrier use and pressed them into USAF service. This included the transfer of the piston-engine Douglas A-1 Skyraider in its A-1E and A-1H variants being retired from the Navy inventory in the mid-1960s for close air support, rescue aircraft escort, and special operations duties in Vietnam, as well as the Navy's LTV A-7 Corsair II light attack bomber in new production numbers, the USAF versions of which were designated A-7D and A-7K. In the case of the A-7, the USAF was initially reluctant to take on yet another Navy-designed aircraft, but on 5 November 1965, Secretary of the Air Force Harold Brown and Chief of Staff of the Air Force, General John P. McConnell, announced that USAF had decided to order a version of the aircraft, designated A-7D, for TAC. The first A-7D made its initial flight in April 1968, and deliveries of production models began in December 1968. When A-7D production ended in 1976, LTV had delivered 459 to the U.S. Air Force. These aircraft continued in TAC service until supplanted by F-16 Fighting Falcon or A-10 Thunderbolt II aircraft. Most A-7Ds and all A-7Ks were later transferred to Air National Guard (ANG) units operationally-gained by TAC, remaining in ANG service until 1993 when they, too, were replaced by the F-16 or A-10. Pacific Air Forces and the Vietnam War During the tenure of the Kennedy Administration, as an additional