Project 56 (nuclear test)
{{Short description|Series of 1950s US nuclear tests}}
{{Use mdy dates|date=November 2018}}
{{Infobox nuclear weapons test
|name = Project 56 (nuclear test)
|picture =
|picture_description =
|country = United States
|test_site = NTS, Areas 1–4, 6–10, Yucca Flat
|period = 1955–1956
|number_of_tests = 4
|test_type = dry surface
|max_yield = {{convert|10|tTNT|lk=in}}
|previous_series = Operation Wigwam
|next_series = Operation Redwing
}}
{{GeoGroup|article=Project 56 (nuclear test)}}
Operation Project 56 was a series of 4 nuclear tests conducted by the United States in 1955–1956 at the Nevada Test Site. These tests followed the Operation Wigram series and preceded the Operation Redwing series.
Introduction
These experiments were safety tests, the purpose of which were to determine whether a weapon or warhead damaged in an accident would detonate with a nuclear yield, even if some or all of the high explosive components burned or detonated.{{cite web |title=Operation Wigwam and Project 56 |url=http://nuclearweaponarchive.org/Usa/Tests/Wigwam.html |work=The Nuclear Weapon Archive}}National Nuclear Security Administration / Nevada Site Office, Plutonium Dispersal Tests at the Nevada Test Site, April 2010, [http://www.nv.doe.gov/library/factsheets/DOENV_1046.pdf DOE/NV-1046] {{webarchive|url=https://web.archive.org/web/20110927020910/http://www.nv.doe.gov/library/factsheets/DOENV_1046.pdf |date=September 27, 2011 }} The procedure for these tests was to fault the test bomb by removing a detonator wire, or perhaps all but one, for example, possibly enhancing the weapon with extra initiators or an especially enriched core, and then to fire the weapon normally (see Warhead design safety). If there is any nuclear yield in the firing, then the test is deemed a failure from a safety standpoint. A successful test will measure only the chemical explosive in the test bomb exploding, which still, of course, blasts the bomb core and causes the core material to be spread over a wide area if the test is in open air, as all the Project 56 tests were.
Aftermath
Over {{convert|895|acre}} of Area 11 at the NTS were contaminated with plutonium dust and fragments. The area has become known as Plutonium Valley, and continues to be used on an intermittent basis for realistic drills in radiological monitoring and sampling operations.
{{see also|List of nuclear weapons tests of the United States}}
| dry surface,
safety experiment
| TX-15/39 primary ?
| style="text-align:center;" | {{sort|000000000|no yield}}
|
| One point safety test of sealed pit, successful. Extra oralloy in the core and three zippers were used to make sure of a worst case condition in the pit for supporting fission, which would have been deemed a test failure.
|-
! 2{{anchor|2}}
| {{dts|1955|11|3}} 21:15:??
| style="text-align:center;" | PST (–8 hrs)
|| NTS Area 11b {{coord|36.9801|-115.9594|name=2|display=inline}}
| {{sort|001263|}}{{convert|1263|m|abbr=on}} + 0
| dry surface,
safety experiment
| W-25
| style="text-align:center;" | {{sort|000000000|no yield}}
|
| One point safety test of W-25 sealed pit, successful. 3 zippers used to make sure of plentiful neutrons.
|-
! 3{{anchor|3}}
| {{dts|1955|11|5}} 19:55:??
| style="text-align:center;" | PST (–8 hrs)
|| NTS Area 11c {{coord|36.97572|-115.95732|name=3|display=inline}}
| {{sort|001260|}}{{convert|1260|m|abbr=on}} + 0
| dry surface,
safety experiment
| TX/W-28 primary
| style="text-align:center;" | {{sort|000000000|no yield}}
|
| One point safety test of TX/W-28 primary, successful. 3 zippers used to make sure of plentiful neutrons.
|-
! 4{{anchor|4}}
| {{dts|1956|1|18}} 21:30:??
| style="text-align:center;" | PST (–8 hrs)
|| NTS Area 11d {{coord|36.97135|-115.95539|name=4|display=inline}}
| {{sort|001252|}}{{convert|1252|m|abbr=on}} + 0
| dry surface,
safety experiment
| TX/W-28 primary
| style="text-align:center;" | {{sort|000000100|10 t}}
|
| One point safety test partial failure, due to large neutron initiation (6 zippers) in what would otherwise have been a just-barely-critical device.
|}
{{reflist|group=note}}
See also
Further reading
* Hansen, Chuck, "[http://www.uscoldwar.com/ Swords of Armageddon]" (CD-ROM & download available). PDF. 2,600 pages, Sunnyvale, California, Chucklea Publications, 1995, 2007. {{ISBN|978-0-9791915-0-3}} (2nd Ed.)
References
{{reflist|25em|refs=
}}
{{Department of Energy}}
{{US Nuclear Tests}}
Category:1955 in military history
Category:1956 in military history