On 24th January 1961, a B-52 Stratofortress broke up in mid-air near Goldsboro, North Carolina, dropping two Mark 39 nuclear bombs it carried.
On that day in January of 1961, the B-52G Stratofortress 58-0187 of the Strategic Air Command USAF, took-off from Seymour Johnson Air Force Base in Goldsboro, for a mission around the East Coast. It was a routine flight within Cover All operation, during which strategic bomber aircraft were continually airborne and ready to attack targets in the Soviet Union (Cover All was a predecessor of more advanced Operation Chrome Dome, launched later that year). Following the mission objectives, the B-52 was carrying two Mark 39 Mod 2 hydrogen nuclear bombs, 3.8 megatons each.
The flight route included a few scheduled aerial re-fuelling procedures and one of them was planned to be executed around midnight on 23-24 January.
At some point during the ongoing re-fuelling procedure, the tanker crew noticed a fuel leak on the right wing of the B-52 bomber. The Stratofortress commander, Major Walter Scott Tulloch was informed about the situation, and the re-fuelling was aborted.
After reporting this situation to the ground control station, a holding pattern over the Atlantic was designated for the B-52 to burn out the excessive fuel. However, the leak was already so intensive, that the aircraft lost 17,000 kg (37,000 pounds) of fuel in just three minutes. The Stratofortress was ordered to return to base immediately, but soon after descending procedure was initiated, approximately at 3,000 metres (10,000 feet) and on approach pattern, the crew lost control on the aircraft.
Tulloch ordered to abandon the aeroplane and six crew members bailed out successfully but, regrettably, one of them was killed during landing with parachute. Two other aviators did not managed to leave the Stratofortress and they were still on board when the B-52 broke up in mid-air. They both did not survive the accident. About half an hour after midnight, the Stratofortress crashed approximately 19 kilometres north from Goldsboro. The remains of the aircraft covered an area of 5.2 square kilometres.
Details about the incident, including the status of the aforementioned two Mark 39 hydrogen bombs, remained classified until 2013. Then, the information about the load was released to public and confirmed how close it was at the time to a nuclear disaster.
Both bombs separated from the B-52 after the aircraft broke up. The first one deployed its parachute and was soon found standing on the ground with the parachute hanging on a tree. However, the most shocking thing was that Mark 39 was nearly fully armed. According to official documents, only one of four safety devices – the single safe/arm switch – remained in ´safe´ position and prevented North Carolina from the nuclear explosion.
Remains of the second bomb were later discovered on a muddy field, with some of its parts plunged deep beneath the ground. Fortunately, the second Mark 39 bomb did not explode either. However, it was as close to the nuclear disaster as it was with the first one. The bomb was armed, with its switch in ´arm´ position, and it was just the high-voltage switch that remained open and put the explosion on hold.
Moreover, due to groundwater flooding in the area, extraction of the second bomb was not possible. Only a few parts were recovered but the main component with its thermonuclear load, including uranium and plutonium, still remains in place.
Investigation on the crash, led by the USAF, has later found that the disaster was caused by structural failure of the aircraft, due to construction defect on the B-52 wings and fuel tanks.
Although the operation Cover All lasted just a few months and its scale was limited, it marked history of aviation with two Broken Arrow incidents (an US codename for an unexpected event with nuclear weapon). The second one occurred in less than two months from Goldsboro crash, on 14th March 1961. And, similarly to the first case, it also included two nuclear weapons lost during another B-52 crash. However, this time the safety devices worked properly, and the bombs remained in ´safe´ mode.
Interesting fact is that, in 2012, the town of Eureka which is located approximately 5 kilometres from the crash site, erected there a dedicated road sign to commemorate the ´Nuclear Mishap´.
