A few members of an advance party from the 12th Combat Support Group arrived at Cam Ranh Bay in August 1965.

12th TFW squadrons initially scheduled for November deployment were: 555th, 557th and 558th Tactical Fighter Squadrons, 12th Armament and Electronics Maintenance Squadron, 12th Field Maintenance Squadron and 412th Munitions Maintenance Squadron. Ultimatly the 559th TFS took the place of the 555th when the latter was diverted to Okinawa and Thailand.

The new airfield at Cam Ranh Bay was ready, as scheduled, November 1, 1965. The 43d TFS (15th TFW), which had just begun a quarterly rotation at Clark AB, was diverted to Cam Ranh Bay. The 558th TFS, followed by the 557th also arrived in November. On January 1, 1966 the personnel of the 559th TFS arrived and accepted the aircraft left behind by the departing 43d.

Construction problems delayed the opening of the new airfield at Phan Rang. Because the 366th TFW was unable to deploy to that base in January 1966 as scheduled, its 391st TFS was attached, and later assigned, to the 12th TFW at Cam Ranh Bay.