Operation Project 58/58A was a series of 4

nuclear test Nuclear weapons tests are experiments carried out to determine nuclear weapons' effectiveness, Nuclear weapon yield, yield, and explosive capability. Testing nuclear weapons offers practical information about how the weapons function, how detona ...

s conducted by the United States in 1957–1958 at the

Nevada Test Site The Nevada National Security Site (N2S2 or NNSS), known as the Nevada Test Site (NTS) until 2010, is a United States Department of Energy (DOE) reservation located in southeastern Nye County, Nevada, about 65 miles (105 km) northwest of the ...

. These tests followed the ''

Operation Plumbbob Operation Plumbbob was a series of nuclear tests that were conducted between May 28 and October 7, 1957, at the Nevada Test Site, following '' Project 57'', and preceding '' Project 58/58A''. Background The operation consisted of 29 explosion ...

'' series and preceded the ''

Operation Hardtack I Operation Hardtack I was a series of 35 nuclear tests conducted by the United States from April 28 to August 18 in 1958 at the Pacific Proving Grounds. At the time of testing, the Operation Hardtack I test series included more nuclear detonation ...

'' series. All the tests in ''Project 58'' were one-point safety tests. They were intended to freeze device designs prior to full-scale tests at ''

''. No significant yield was expected from either, but the second, ''Coulomb-C'', a surface test conducted on December 9, produced an unanticipated yield of 500 tons. Shortly after detonation, fallout readings of fifty roentgens per hour were recorded on the Mercury Highway, and, as the cloud moved toward the southwest, personnel at Jackass Flats involved in construction for future nuclear rocket testing were forced to take cover. Eventually, the cloud reached the Los Angeles area where readings caused public concern.U.S. Department of Energy, ''Battlefield of the Cold War, The Nevada Test Site, Volume 1, Atmospheric Nuclear Weapons Testing, 1951-1963''
DOE/MA-0003

References

{{DEFAULTSORT:Project 58 58A 1957 in Nevada 1958 in Nevada Explosions in 1957 Explosions in 1958 1957 in military history 1958 in military history Nevada Test Site nuclear explosive tests