Nuclear explosion debris. The first man made nuclear explosion occurred on July 16, 1945 at 5:50 am on the Trinity Test Site near Alamogordo, New Mexico in the United States, an area now known as the White Sands Missile Range. The event involved the full-scale testing of an implosion-type fission atomic bomb. In a memorandum to the U.S. Secretary of War, General Leslie Groves describes the yield as equivalent to 15,000 to 20,000 tons of TNT. Following this test, a uranium-gun type nuclear bomb (Little Boy) was dropped on the Japanese city of Hiroshima on August 6, 1945, with a blast yield
393d Bomb Squadron atomic bomb delivery techniques. The squadron carried out two Atomic Bombing missions over Japan in August 1945, being the only squadron in the world to ever carry out and deliver nuclear weapons in combat. Dropped the first atomic bomb on Hiroshima, Japan, on 6 August 1945, and the second atomic bomb on Nagasaki, Japan, on 9 August 1945. Reassigned to the United States in November 1945, becoming part of Continental Air Forces (later Strategic Air Command). Deployed to Kwajalein in 1946 to carry out Operation Crossroads atomic bomb tests on Bikini Atoll in July. Began upgrading to the new Boeing