Project 56 (nuclear test)

Project 56 (nuclear test)
Information
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	10 tonnes of TNT (42 GJ)
Navigation
Previous test series	Operation Wigwam
Next test series	Operation Redwing

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 Wigwam 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. 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 895 acres (362 ha) 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

United States' Project 56 series tests and detonations

Name	Date time (UT)	Local time zone	Location	Elevation + height	Delivery Purpose	Device	Yield	Fallout	References	Notes
1	1 November 1955 22:10:??	PST (-8 hrs)	NTS Area 11a	1,271 m (4,170 ft) + 0	dry surface, safety experiment	TX-15/39 primary ?	no yield			One point safety test of sealed pit, successful. Extra oralloy and 3 zippers used to make sure of plentiful neutrons.
2	3 November 1955 21:15:??	PST (-8 hrs)	NTS Area 11b	1,263 m (4,144 ft) + 0	dry surface, safety experiment	W-25	no yield			One point safety test of W-25 sealed pit, successful. 3 zippers used to make sure of plentiful neutrons.
3	5 November 1955 19:55:??	PST (-8 hrs)	NTS Area 11c	1,260 m (4,130 ft) + 0	dry surface, safety experiment	TX/W-28 primary	no yield			One point safety test of TX/W-28 primary, successful. 3 zippers used to make sure of plentiful neutrons.
4	18 January 1956 21:30:??	PST (-8 hrs)	NTS Area 11d	1,252 m (4,108 ft) + 0	dry surface, safety experiment	TX/W-28 primary	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.

See also

• Project 57
• Operation Roller Coaster
• Nuclear weapon design

Further reading

• Hansen, Chuck, "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

 This article incorporates public domain material from websites or documents of the United States Department of Energy.