An accident occurred in Goldsboro, North Carolina in 1961. A B-52 Stratofortress carrying two Mark 39 nuclear bombs broke up in mid-air, dropping its nuclear payload in the process. The two 3-4 megaton nuclear bombs separated from the gyrating aircraft as it broke up between 10,000 and 2,000 ft. One of the bombs activated, causing it to execute many of the steps needed to arm itself, such as charging the firing capacitors and, critically, deployment of a 100-foot-diameter retard parachute. The bomb that descended by parachute was found intact, and standing upright as a result of its parachute being caught in a tree. According to the bomb disposal expert responsible for disarming the device, the arm/safe switch was still in the safe position, though it had completed the rest of the arming sequence. The Pentagon claimed at the time that there was no chance of an explosion and that two arming mechanisms had not activated. In 2013, information released as a result of a Freedom of Information Act request confirmed a single switch prevented detonation.