One of the longest-serving nuclear weapons in America’s arsenal is the B61 nuclear free-fall bomb. The B61 bomb was first introduced in 1966 with more than three thousand bombs produced to date. The bomb is famous for its adjustable yield capability, giving it the versatility to operate in both the tactical and strategic nuclear roles. The United States forward deploys many of the bombs in Europe, with up to fifty bombs currently maintained at Incirlik Air Force Base in Turkey.
In 1960, Sandia National Laboratory and Los Alamos Scientific Laboratory began development of a new nuclear free-fall bomb. The bomb, nicknamed FUFO (full fuzing option), would be capable of adjusting its explosive yield to the mission, high-speed or low-speed delivery, high altitude or low altitude delivery, and airburst or contact burst fuzing capability. Each B61 is 11.8 feet long, 13 inches wide and weighs approximately 700 pounds. (The B61-11, an earth-penetrating version of the bomb, weighs an extra 450 pounds.)
Even fewer B61 tactical bombs are on active deployment. The BOAS estimates the Air Force deploys 230 tactical versions of the B61 bomb, B61-3 and B61-4, with 160 in Western Europe and Turkey. The Federation of American Scientists assesses twenty B61-3/4s at Kleine Brogel Air Base in Belgium, twenty at Buchel Air Base in Germany, twenty at Aviano Air Base and twenty at Ghedi Air Base in Italy, twenty at Volkel Air Base in The Netherlands, and fifty at Incirlik Air Base in Turkey. Experts believe the remainder are in storage at the sprawling Kirtland Underground Munitions and Maintenance Storage Complex (KUMMSC) outside Albuquerque, New Mexico.
Read more at America Built 3,155 B61 Nuclear Bombs. Around 50 Are Still in Turkey