4042d Airborne Missile Maintenance Squadron was activated in November to maintain these missiles. However, SAC Strategic Wings could not carry a permanent history or lineage and SAC looked for a way to make its Strategic Wings permanent. In 1962, Headquarters SAC received authority from Headquarters USAF to discontinue its Major Command controlled (MAJCON) strategic wings that were equipped with combat aircraft and to replace them with Air Force controlled (AFCON) units, which could carry a lineage and history. 306th Bombardment Wing As a result, the 4047th SW was replaced by the 306th Bombardment Wing, which assumed its mission, personnel, and equipment on 1 April 1963. In the same way the 367th Bombardment Squadron, one of the unit's World War II historical bomb squadrons, replaced the 347th BS. The 813d Medical Group, 39th Munitions Maintenance Squadron and the 306th Air Refueling Squadron were reassigned to the 306th. Component support units were replaced by units with numerical designation of the 306th. Under the Dual Deputate organization, all flying and maintenance squadrons were directly assigned to the wing, so no operational group was activated, although the 306th Combat Support Group became the wing's administrative support unit. Each of the new units assumed the personnel, equipment, and mission of its predecessor. Immediately after the move to McCoy, the 306th began transitioning to the B-52D version of the Stratofortress during the spring and summer of 1963 and assumed strategic nuclear alert duties under SAC's Operation Chrome Dome airborne alert program. Under this program, each SAC bomb wing was periodically tasked, for a specified period of time, to maintain a portion of its bombers airborne and ready to strike. On 16 November 1963, two of eight ground alert lines maintained by the wing's 367th BS were converted to airborne alert lines. Two B-52Ds were flown in cell along the southern Chrome Dome route across Spain to the Mediterranean every day until 31 December 1963. Each B-52D required two air refuelings inbound to Spain and two more outbound over the Mediterranean, with mission duration averaging 25 to 27 hours in length. The 306th Air Refueling Squadron ground alert was also degraded to support Chrome Dome refueling along the southern route. The 306 BW was tasked to maintain airborne alert several more times until the wing deployed to support conventional bombing operations in Southeast Asia in 1966. Ground alert was reinstated at the SAC directed 50 percent of