Naval Shipyard. The U.S. Air Force assumed control of the airport in 1951, when the installation was selected for development as a Strategic Air Command (SAC) base. Purchase of additional land for expansion of the base started in 1952 and was completed in 1956. Ground breaking for the new SAC facilities took place in 1954, and the first B-47 Stratojet bombers arrived in 1956. Renamed Portsmouth Air Force Base, the installation formally opened on 30 June 1956. On 7 September 1957, it was renamed Pease Air Force Base in honor of New Hampshire native Captain Harl Pease, Jr., USAAC, who was posthumously awarded the Medal of Honor for heroism during World War II. Pease AFB was the home of the 100th Bombardment Wing and from 1958 onward the 509th Bombardment Wing, the latter arriving from Walker AFB, New Mexico, as successor to the famed 509th Composite Group of World War II that had executed the atomic bombings of Hiroshima and Nagasaki and had transitioned to the B-47 and KC-97 in the mid-1950s. Their mission was strategic warfare in the event of war. From 1956 until its closure in 1991, Pease Air Force Base maintained a combat-ready force for long-range bombardment and nuclear strikes. B-47 Stratojet, B-52 Stratofortress, and FB-111 Aardvark bomber aircraft, as well as KC-97 Stratofreighter and KC-135 Stratotanker air refueling aircraft and C-97 Stratofreighter, C-124 Globemaster and C-130 Hercules cargo aircraft, were all based at Pease AFB at varying times. In 1961 and 1962, the base received consideration as a potential site for Minuteman missile deployments. The 100th Bombardment Wing was converted in June 1966 to a strategic reconnaissance wing and transferred to Davis-Monthan AFB, Arizona. This left the 509th Bombardment Wing as the principal host wing for Pease AFB. The 509th was phased down for inactivation in 1965, but, cognizant of the historical significance of the 509th in SAC, the wing converted to the B-52D and KC-135A and was redesignated as the 509th Bombardment Wing, Heavy, in 1966. From 1 April to 1 October 1968 and from 26 March to 20 September 1969, more than one-half of the wing was deployed in Southeast Asia. The 509th supported SAC combat and contingency operations in Southeast Asia with KC–135A aircraft and crews from 1966 to 1975, and with B–52D aircraft and crews from 1966 to 1970. By 1 December 1969, the wing had transferred all its B-52D aircraft to