was a floating mass of ice which closely resembled an island. It became known as "Target X", later designated "T-1". T-1 was monitored for three years, as it drifted over 1,500 miles and finally disappeared near Greenland in 1949. The Russians had begun drift station research a decade earlier. In 1937, they undertook scientific experiments from a drifting ice station near the North Pole, and they had followed that up after the war with an accelerated program of ice pack investigations. In July 1950, "T-2" was spotted about 300 miles south of the North Pole. About a week later "T-3" was spotted 300 miles east of the Soviet Wrangel Island as it drifted towards the North Pole. After studies and testing of proposed Ice Station research north of Point Barrow, in March 1952, a C-47 was landed successfully on T-3. During the 1950s, the Ice Station established there hosted joint military-civilian scientific parties during several lengthy occupations under "Project Icicle". Under Project Ice Skate, the station was used again during the International Geophysical Year (IGY) of 1957–58 and beyond. Over the years, T-3 drifted across the Arctic basin, leaving the zone of AAC support periodically, and occasionally drifting close to Soviet waters across the International Date Line. During the IGY, when T-3 had drifted to Greenland, two other stations were established in the western Arctic as pack ice stations. Ice Station Alpha was occupied from 1957-late 1958. When it began to break up, crews established a new station the following spring. Known as Ice Station Charlie, it lasted ten months before meeting the same fate. In 1961, USAF ended its sponsorship of ice station research, turning its remaining facilities on T-3 over to the Navy. Ballistic Missile Early Warning System Budget reductions beginning in the late 1950s and the demands of the Vietnam War in the 1960s led to a major reduction in AAC's forces. The development of Intercontinental ballistic missiles (ICBM) and Submarine-launched ballistic missiles forced Air Force planners to redirect its air defensive systems for ballistic missile detection and warning and space surveillance, and the atmospheric detection and warning system, which had been in an almost continuous state of expansion and improvement since the late 1940s, went into decline. The number of fighter interceptor squadrons shrank to one, the 10th and 11th air divisions were inactivated in 1960, and the aircraft control and warning sites declined to 13.