Operation Tumbler–Snapper

Operation Tumbler–Snapper was a series of nuclear weapons tests conducted by the United States in early 1952 at the Nevada Test Site. The Tumbler–Snapper series of tests followed Operation Buster–Jangle and preceded Operation Ivy.

Operation Tumbler–Snapper
Tumbler-Snapper Dog, 19 kilotons
Information
Country	United States
Test site	NTS Areas 5, 11, Frenchman Flat NTS, Areas 1–4, 6–10, Yucca Flat
Period	1952
Number of tests	8
Test type	free air drop, tower
Max. yield	31 kilotonnes of TNT (130 TJ)
Test series chronology
← Operation Buster–Jangle Operation Ivy →

Tests

Tumbler

The Tumbler phase, sponsored by the Atomic Energy Commission, consisted of three airdrops intended to help explain discrepancies in the actual and estimated blast shock wave damage noted on previous detonations and to establish more accurately the optimal height of burst.

Snapper

The Snapper phase, sponsored by the Department of Defense, consisted of one airdrop and four tower shots intended to test various new weapons developments.^[1]

The military exercise Desert Rock IV, involving 7350 soldiers, took place during the test series. They trained during the Charlie, Dog, and George shots and observed shot Fox.^[2]

Aftermath

The Tumbler-Snapper detonations included some particularly fallout-heavy weapons. Of particular note is shot George, which contaminated more citizens than any other nuclear test in the United States. George alone accounted for some 7 percent of all population exposure to radiation during the 1,032 nuclear tests performed by the United States.^[3][4]

The ten highest radiation exposures to residents from US continental nuclear testing, with shot George in the first column.

Summary

See also: List of nuclear weapons tests of the United States

United States' Tumbler–Snapper series tests and detonations

Name [note 1]	Date time (UT)	Local time zone[note 2][5]	Location[note 3]	Elevation + height [note 4]	Delivery,[note 5] Purpose [note 6]	Device[note 7]	Yield[note 8]	Fallout[note 9]	References	Notes
Able	April 1, 1952 17:00:07.5	PST (−8 h)	NTS Area 5 36.7983°N 115.9364°W / 36.7983; -115.9364 (Able)	940 m (3,080 ft) + 240 m (790 ft)	free air drop, weapon effect	Mk-4	1 kt	iodine-131 venting detected, 140 kCi (5,200 TBq)	[6][7][8][9][10]	U-235 core, same as Ranger Able. Same scale height as Hiroshima and Buster Baker in order to recreate similar blast conditions on a different type of surface.
Baker	April 15, 1952 17:29:57.1	PST (−8 h)	NTS Area 7 37.0841°N 116.0203°W / 37.0841; -116.0203 (Baker)	1,280 m (4,200 ft) + 340 m (1,120 ft)	free air drop, weapon effect	Mk-4	1 kt	iodine-131 venting detected, 140 kCi (5,200 TBq)	[6][7][8][9][10]	Repeat of Tumbler Able but on the Buster area at a higher height of burst.
Charlie	April 22, 1952 17:30:10.0	PST (−8 h)	NTS Area 7 37.0844°N 116.0211°W / 37.0844; -116.0211 (Charlie)	1,280 m (4,200 ft) + 1,050 m (3,440 ft)	free air drop, weapon effect, weapons development	Mk-4	31 kt	iodine-131 venting detected, 4.6 MCi (170 PBq)	[6][7][8][9][10]	Same scale height as Tumbler Baker in order to check the applicability of cube root blast scaling. Proof test of new core (?). First blast broadcast live on TV. Desert Rock IV.
Dog	May 1, 1952 16:29:59.1	PST (−8 h)	NTS Area 7 37.0841°N 116.0211°W / 37.0841; -116.0211 (Dog)	1,280 m (4,200 ft) + 320 m (1,050 ft)	free air drop, weapon effect, weapons development	TX-7	19 kt	iodine-131 venting detected, 2.9 MCi (110 PBq)	[6][7][8][9][10]	Same scale height as Buster Charlie and Easy. First boosted fission test in CONUS. Tested deuterium (without tritium) gas fusion boosting. First detection of a precursor pressure wave. Desert Rock IV.
Easy	May 7, 1952 12:14:59.3	PST (−8 h)	NTS Area 1 37.053°N 116.1064°W / 37.053; -116.1064 (Easy)	1,294 m (4,245 ft) + 90 m (300 ft)	tower, weapons development	Mk-12 "BROK-1"	12 kt	iodine-131 venting detected, 1.8 MCi (67 PBq)	[6][7][8][9][10]	First use of beryllium as tamper.
Fox	May 25, 1952 11:59:59.6	PST (−8 h)	NTS Area 4 37.0955°N 116.1064°W / 37.0955; -116.1064 (Fox)	1,300 m (4,300 ft) + 90 m (300 ft)	tower, weapons development	TX-5 "XR1"	11 kt	iodine-131 venting detected, 1.6 MCi (59 PBq)	[6][7][8][9][10]	Designed to test the initiation/yield curve. Calibration test for TOM polonium/beryllium internal initiator. Desert Rock IV.
George	June 1, 1952 11:54:59.8	PST (−8 h)	NTS Area 3 37.048°N 116.022°W / 37.048; -116.022 (George)	1,229 m (4,032 ft) + 90 m (300 ft)	tower, weapons development	TX-5 "XR-2"	15 kt	iodine-131 venting detected, 2.2 MCi (81 PBq)	[6][7][8][9][10]	Tested an external betatron initiator that shot x-rays into the core, which induced neutrons by photofission. Desert Rock IV.
How	June 5, 1952 11:55:00.3	PST (−8 h)	NTS Area 2 37.1386°N 116.1187°W / 37.1386; -116.1187 (How)	1,370 m (4,490 ft) + 90 m (300 ft)	tower, weapons development	TX-12 "Scorpion"	14 kt	iodine-131 venting detected, 2.1 MCi (78 PBq)	[6][7][8][9][10]	First test to use a beryllium neutron reflector/tamper.

1. The US, France and Great Britain have code-named their test events, while the USSR and China did not, and therefore have only test numbers (with some exceptions – Soviet peaceful explosions were named). Word translations into English in parentheses unless the name is a proper noun. A dash followed by a number indicates a member of a salvo event. The US also sometimes named the individual explosions in such a salvo test, which results in "name1 – 1(with name2)". If test is canceled or aborted, then the row data like date and location discloses the intended plans, where known.
2. To convert the UT time into standard local, add the number of hours in parentheses to the UT time; for local daylight saving time, add one additional hour. If the result is earlier than 00:00, add 24 hours and subtract 1 from the day; if it is 24:00 or later, subtract 24 hours and add 1 to the day. Historical time zone data obtained from the IANA time zone database.
3. Rough place name and a latitude/longitude reference; for rocket-carried tests, the launch location is specified before the detonation location, if known. Some locations are extremely accurate; others (like airdrops and space blasts) may be quite inaccurate. "~" indicates a likely pro-forma rough location, shared with other tests in that same area.
4. Elevation is the ground level at the point directly below the explosion relative to sea level; height is the additional distance added or subtracted by tower, balloon, shaft, tunnel, air drop or other contrivance. For rocket bursts the ground level is "N/A". In some cases it is not clear if the height is absolute or relative to ground, for example, Plumbbob/John. No number or units indicates the value is unknown, while "0" means zero. Sorting on this column is by elevation and height added together.
5. Atmospheric, airdrop, balloon, gun, cruise missile, rocket, surface, tower, and barge are all disallowed by the Partial Nuclear Test Ban Treaty. Sealed shaft and tunnel are underground, and remained useful under the PTBT. Intentional cratering tests are borderline; they occurred under the treaty, were sometimes protested, and generally overlooked if the test was declared to be a peaceful use.
6. Include weapons development, weapon effects, safety test, transport safety test, war, science, joint verification and industrial/peaceful, which may be further broken down.
7. Designations for test items where known, "?" indicates some uncertainty about the preceding value, nicknames for particular devices in quotes. This category of information is often not officially disclosed.
8. Estimated energy yield in tons, kilotons, and megatons. A ton of TNT equivalent is defined as 4.184 gigajoules (1 gigacalorie).
9. Radioactive emission to the atmosphere aside from prompt neutrons, where known. The measured species is only iodine-131 if mentioned, otherwise it is all species. No entry means unknown, probably none if underground and "all" if not; otherwise notation for whether measured on the site only or off the site, where known, and the measured amount of radioactivity released.

Video

A photographic-study of blast and thermal phenomena - Operation TUMBLER.

Gallery

• 
  Tumbler-Snapper Able, 1-kiloton.
• 
  Tumbler-Snapper Charlie, 31-kilotons.
• 
  Tumbler-Snapper Dog, 19-kilotons.
• 
  Tumbler-Snapper Fox, 11-kilotons.
• 
  Tumbler-Snapper George, 15-kilotons.
• 
  Tumbler-Snapper How, 14-kilotons.

References

1. Byrnes, V. A. (1953). Flash blindness. Operation SNAPPER. Nevada Proving Grounds, April–June 1952, Project 4.5. School of Aerospace Medicine. Brooks A.F.B. Texas.
2. "Operation Tumbler Snapper Fact Sheet" (PDF). Defense Threat Reduction Agency. Archived from the original (PDF) on February 18, 2013. Retrieved October 26, 2013.
3. "The United States' Nuclear Testing Programme: CTBTO Preparatory Commission". www.ctbto.org. Retrieved July 6, 2022.
4. "You'll Marvel At the Largest Man-Made Crater from the Atomic Age in Nevada". Only In Your State. December 16, 2016. Retrieved December 24, 2021.
5. "Time Zone Historical Database". iana.com. Retrieved March 8, 2014.
6. Estimated exposures and thyroid doses received by the American people from Iodine-131 in fallout following Nevada atmospheric nuclear bomb tests, Chapter 2 (PDF), National Cancer Institute, 1997, archived from the original (PDF) on January 17, 2009, retrieved January 5, 2014
7. Sublette, Carey, Nuclear Weapons Archive, retrieved January 6, 2014
8. Hansen, Chuck (1995), The Swords of Armageddon, Vol. 8, Sunnyvale, CA: Chukelea Publications, ISBN 978-0-9791915-1-0
9. United States Nuclear Tests: July 1945 through September 1992 (PDF) (DOE/NV-209 REV15), Las Vegas, NV: Department of Energy, Nevada Operations Office, December 1, 2000, archived from the original (PDF) on October 12, 2006, retrieved December 18, 2013
10. Yang, Xiaoping; North, Robert; Romney, Carl (August 2000), CMR Nuclear Explosion Database (Revision 3), SMDC Monitoring Research

• Robert Standish Norris and Thomas B. Cochran. "United States Nuclear Tests July 1945 to 31 December 1992" (PDF). Archived from the original (PDF) on September 27, 2014. Retrieved November 12, 2007.
• Griggs, D. T.; Frank Press (1961). "Probing the earth with nuclear explosions". Journal of Geophysical Research. 66 (1): 237–258. Bibcode:1961JGR....66..237G. doi:10.1029/jz066i001p00237. hdl:2027/mdp.39015077588872.

External links

• Nuclear Test Film – Operation Tumbler-Snapper (1952) is available for free viewing and download at the Internet Archive
• The short film A-Bomb Blast Effects (1959) is available for free viewing and download at the Internet Archive.