HDT WHAT? INDEX SOME CALLS ARE CLOSER THAN OTHERS CLOSE CALLS There was a steam explosion and fire in an atomic pile at Leipzig shortly after Werner Heisenberg and Robert Döpel had used it to generate Nazi Germany’s 1st signals of neutron propagation. While checking their device for a possible heavy-water leak, air June 23, 1942 got in and the device’s uranium powder ignited. This caused the water jacket to boil and generated enough steam pressure to blow the pile apart, scattering burning ura- nium powder throughout the lab. There was an unexpected criticality nuclear reaction at the Los Alamos Scientific Laboratory. The material went beyond criticality into prompt-criticality, which is the February 11, 1945 next stage after criticality in the generation of a bomb-like nuclear detonation. This was the 1st time in the history of the US’s nuclear program that such a supremely dan- gerous Chernobyl-like event had occurred in the laboratory. At the Omega site in Los Alamos National Laboratory, New Mexico, Harry K. Dagh- lian, Jr. inadvertently creating a critical mass when he dropped a tungsten carbide August 21, 1945 brick onto a plutonium core. Although he quickly removed the brick he had been fatally irradiated, and would die on September 15th. At Los Alamos National Laboratory, New Mexico there was another accidental criti- cality. Demonstrating his technique for the benefit of 7 visitors, Louis Slotin used a screwdriver to manually assemble a critical mass of plutonium. His hand slipped. May 21, 1946 He received an estimated dose of 1,000 rads (rad), or 10 grays (Gy) and would die on May 30th. The observers received doses as high as 166 rads but survived, although 3 of them would die within a few decades from conditions presumed to be radiation- related. For the 2d time in the history of our nuclear program, at the Los Alamos Scientific December 1949 Laboratory, some fissile material went beyond criticality into prompt-criticality, the final stage before a nuclear blast. A B-36 was flying a simulated combat mission in a test of its ability to carry nuclear payloads, off the coast of British Columbia over the Pacific Ocean, from Eielson Air Force Base near Fairbanks, Alaska to Carswell Air Force Base in Fort Worth, Texas, carrying a weapon that had a dummy warhead. The device contained conventional explosives and natural uranium but lacked the plutonium needed to create a nuclear explosion. They experienced mechanical problems and were forced to shut down 3 of February 13, 1950 6 engines of the bomber at an altitude of 12,000 feet. Fearing that severe weather and icing would jeopardize an emergency landing, and aware the TNT might explode, they jettisoned the device over the Pacific Ocean at a height of 8,000 feet. The device’s high explosives detonated upon impact with a bright flash. All 16 crew mem- bers and a passenger parachuted and 12 would be subsequently recovered from Prin- cess Royal Island. The Pentagon’s summary report neglects to mention whether any of the natural uranium was later recovered. At Albuquerque, New Mexico, 3 minutes after departure from Kirtland Air Force Base, a B-29 bomber carrying a nuclear device and 4 spare detonators crashed into a mountain near Manzano Base. An atomic explosion was not likely because, for safety April 11, 1950 reasons, the weapon’s core was outside the weapon. The crash resulted in a fire visi- ble from 15 miles and all 13 crewmen were killed. The device’s high explosives ignited upon contact with the plane’s burning fuel. The 4 spare detonators and all nuclear materials would be recovered. HDT WHAT? INDEX SOME CALLS ARE CLOSER THAN OTHERS CLOSE CALLS A B-50 aircraft on a training mission from Biggs Air Force Base with a nuclear July 13, 1950 weapon aboard flew into the ground at Lebanon, Ohio. High explosives scattered nuclear materials but there was no nuclear explosion. At Fairfield-Suisun Air Force Base in California there was the non-nuclear detonation when a B-29 bomber with a Mark 4 atomic bomb on board, heading for Guam, expe- August 5, 1950 rienced malfunctions with 2 props and with landing gear retraction during takeoff and crashed while circling back. In the crash the bomb’s high explosives killed 19 includ- ing the pilot, Brigadier-General Robert F. Travis. At Rivière-du-Loup, Québec, an atomic bomb into which the plutonium core had not been inserted detonated in a non-nuclear manner. A B-50 was bringing back one of several Mark 4 nuclear bombs that we had secretly deployed in Canada, when it had November 10, 1950 engine trouble and jettisoned the device at 10,500 feet above the St. Lawrence River. The crew set the device to self-destruct at 2,500 feet. The explosion shook area resi- dents and scattered nearly 100 pounds of Uranium-238 that had been in the weapon’s tamper. For the 3d time in the history of our nuclear program, at the Los Alamos Scientific February 1, 1951 Laboratory, some fissile material went beyond criticality into prompt-criticality, the final stage before an atomic explosion. For the 4th time in the history of our nuclear program, at the Los Alamos Scientific April 18, 1952 Laboratory, some fissile material went beyond criticality into prompt-criticality, the final stage before an atomic explosion. For the 5th time in the history of our nuclear program, at the Los Alamos Scientific June 2, 1952 Laboratory, some fissile material went beyond criticality into prompt-criticality, the final stage before an atomic explosion. Technicians mistakenly pulled 4 of the 12 control rods out of the fuel core of the experimental NRX nuclear reactor (NRX = “National Research Experimental”) at Atomic Energy of Canada’s Chalk River Laboratories, northwest of Ottawa. There December 12, 1952 was a power surge, partial loss of coolant, and partial core meltdown, followed by an explosion, in which the core was rendered unusable and 4,000,000 liters of radioac- tive water flooded the building’s basement. At Bikini Atoll in the Marshall Islands during the Castle Bravo test of the 1st deploy- able hydrogen bomb, the explosion was more than twice as large as anticipated. Of the total yield equivalent to 15 megatons of TNT, 10 megatons were from fission of the natural uranium tamper and these fission reactions produced a great deal of dirty- March 1, 1954 bomb fallout. Due to an unanticipated wind shift, the radioactive fallout spread into unexpected areas. A 23-man Japanese fishing boat, Daigo Fukuryu Maru or Lucky Dragon, was dosed and many crewmen developed radiation sickness, with a fatality. The fallout spread eastward onto the inhabited Rongelap and Rongerik Atolls, which had not been evacuated, and many Marshall Islanders have suffered radiation burns. For the 6th time in the history of our nuclear program, at the Oak Ridge National Lab- May 26, 1954 oratory some fissile material went beyond criticality into prompt-criticality, the final stage before an atomic explosion. Operator error caused a partial core meltdown in an experimental EBR-I breeder reac- November 29, 1955 tor in Idaho. HDT WHAT? INDEX SOME CALLS ARE CLOSER THAN OTHERS CLOSE CALLS For the 7th time in the history of our nuclear program, at the Oak Ridge National Lab- February 1, 1956 oratory some fissile material went beyond criticality into prompt-criticality, the final stage before an atomic explosion. A B-47 Stratojet on a non-stop mission from MacDill Air Force Base in Florida to an overseas base while carrying 2 nuclear weapon cores descended into a cloud forma- March 10, 1956 tion at 14,000 feet over the Mediterranean Sea for in-air refueling, and disappeared. Neither wreckage nor the cores have been located. For the 8th time in the history of our nuclear program, at the Los Alamos Scientific July 3, 1956 Laboratory some fissile material went beyond criticality into prompt-criticality, the final stage before an atomic explosion. At RAF Lakenheath in Suffolk, England, a B-47 crashed into a storage igloo and July 27, 1956 burning fuel covered 3 Mark-6 nuclear weapons. During the Suez Crisis NORAD received worrisome simultaneous reports of uniden- tified aircraft over Turkey, Soviet MiG-21s over Syria, a downed British bomber, and unexpected maneuvers by the Soviet Black Sea Fleet through the Dardanelles, that might be taken to indicate an offensive by the Soviet Union. The US military com- November 5, 1956 mand worried that our nuclear-armed allies might overreact and make a NATO strike on the USSR. These reports would be resolved as coincidences such as a wedge of swans over Turkey, fighter planes escorting the Syrian president, a British bomber with mechanical issues, and routine scheduled exercises of the Soviet fleet. Accidental venting of extraction wastes by a Soviet Plutonium factory near Kyshtym, 1957 Russia forced a 20-year evacuation of nearly 500 square miles of Western Siberia. For the 9th time in the history of our nuclear program, at the Los Alamos Scientific February 12, 1957 Laboratory some fissile material went beyond criticality into prompt-criticality, the final stage before an atomic explosion. In the vicinity of the “Windscale” facility radioactivity release contaminated about Spring 1957 800 farms. Milk contaminated with Strontium-90 was sold to the public without any warnings. When a B-36 ferrying a nuclear weapon from Biggs Air Force Base dropped it while landing at Kirtland AFB in New Mexico, it struck the ground 4.5 miles south of the May 22, 1957 Kirtland control tower and 0.3 miles west of the Sandia Base reservation and its high explosive material made a crater 12 feet deep and 25 feet in diameter.