Remove ads
The United States's Grommet nuclear test series[1] was a group of 34 nuclear tests conducted in 1971–1972. These tests[note 1] followed the Operation Emery series and preceded the Operation Toggle series.
| Operation Grommet | |
|---|---|
 Grommet Cannikin, 4.8Mt. Largest U.S. Underground nuclear test. | |
| Information | |
| Country | United States |
| Test site |
|
| Period | 1971–1972 |
| Number of tests | 34 |
| Test type | underground shaft, tunnel |
| Max. yield | 4.8 megatonnes of TNT (20 PJ) |
| Test series chronology | |
| Name[note 2] | Date time (UT) | Local time zone[note 3][2] | Location[note 4] | Elevation + height[note 5] | Delivery[note 6] Purpose[note 7] | Device[note 8] | Yield[note 9] | Fallout[note 10] | References | Notes |
|---|---|---|---|---|---|---|---|---|---|---|
| Diamond Mine | July 1, 1971 14:00:00.04 | PST (–8 hrs) | NTS Area U16a.06 37.01148°N 116.20427°W | 1,896 m (6,220 ft) – 266.15 m (873.2 ft) | tunnel, joint verification | less than 20 kt | [1][3][4] | Designed to test detection of underground nuclear tests; see Vela Uniform. | ||
| Miniata | July 8, 1971 14:00:00.082 | PST (–8 hrs) | NTS Area U2bu 37.11018°N 116.05268°W | 1,247 m (4,091 ft) – 528.83 m (1,735.0 ft) | underground shaft, peaceful research | 83 kt | Venting detected, 180 Ci (6,700 GBq) | [1][3][4][5][6][7] | Project Plowshare – device development. | |
| Bracken | July 9, 1971 14:00:00.16 | PST (–8 hrs) | NTS Area U10aq 37.1644°N 116.0336°W | 1,297 m (4,255 ft) – 304.8 m (1,000 ft) | underground shaft, weapons development | 250 t | Venting detected, 1 Ci (37 GBq) | [1][3][4][6][8] | ||
| Apodaca | July 21, 1971 13:33:00.05 | PST (–8 hrs) | NTS Area U3gs 37.01436°N 115.99265°W | 1,195 m (3,921 ft) – 241.4 m (792 ft) | underground shaft, weapons development | 250 t | [1][3][4][8] | |||
| Barranca | August 4, 1971 13:30:00.042 | PST (–8 hrs) | NTS Area U3he 37.02606°N 116.02031°W | 1,187 m (3,894 ft) – 270.74 m (888.3 ft) | underground shaft, weapons development | less than 20 kt | [1][3][4] | |||
| Nama-Amarylis – 1 | August 5, 1971 18:07:45.2 | PST (–8 hrs) | NTS Area U9itsxy3 37.14503°N 116.03417°W | 1,273 m (4,177 ft) – 272.8 m (895 ft) | underground shaft, weapons development | less than 20 kt | [1][3][4] | Simultaneous, separate holes. | ||
| Nama-Mephisto – 2 | August 5, 1971 18:07:45.2 | PST (–8 hrs) | NTS Area U9itsz27 37.14062°N 116.03214°W | 1,276 m (4,186 ft) + | underground shaft, weapons development | less than 20 kt | [1][3][4] | Simultaneous, separate holes. | ||
| Baltic | August 6, 1971 14:31:00.16 | PST (–8 hrs) | NTS Area U9itss25 37.13843°N 116.04182°W | 1,260 m (4,130 ft) – 411.48 m (1,350.0 ft) | underground shaft, weapons development | less than 20 kt | [1][3][4] | |||
| Algodones | August 18, 1971 14:00:00.03 | PST (–8 hrs) | NTS Area U3jn 37.05715°N 116.0372°W | 1,206 m (3,957 ft) – 527.61 m (1,731.0 ft) | underground shaft, weapons development | 67 kt | [1][3][4][7][9] | |||
| Frijoles-Deming – 1 | September 22, 1971 14:00:00.037 | PST (–8 hrs) | NTS Area U3jw 37.02158°N 116.01694°W | 1,186 m (3,891 ft) – 149.86 m (491.7 ft) | underground shaft, safety experiment | 500 t | [1][3][4][8] | Simultaneous, separate holes. | ||
| Frijoles-Espuela – 2 | September 22, 1971 14:00:00.04 | PST (–8 hrs) | NTS Area U3ju 37.02268°N 116.01707°W | 1,186 m (3,891 ft) + | underground shaft, safety experiment | less than 5 kt | [1][3][4] | Simultaneous, separate holes. | ||
| Frijoles-Guaje – 3 | September 22, 1971 14:00:00.04 | PST (–8 hrs) | NTS Area U3hf 37.02438°N 116.01603°W | 1,186 m (3,891 ft) + | underground shaft, weapons development | less than 5 kt | [1][3][4] | Simultaneous, separate holes. | ||
| Frijoles-Petaca – 4 | September 22, 1971 14:00:00.04 | PST (–8 hrs) | NTS Area U3hz 37.02193°N 116.01963°W | 1,185 m (3,888 ft) + | underground shaft, weapons development | less than 5 kt | [1][3][4] | Simultaneous, separate holes. | ||
| Pedernal | September 29, 1971 14:00:00.04 | PST (–8 hrs) | NTS Area U3hg 37.01101°N 116.00809°W | 1,180 m (3,870 ft) – 378.68 m (1,242.4 ft) | underground shaft, weapons development | 4 kt | [1][3][4][9] | |||
| Chantilly | September 29, 1971 14:30:00.14 | PST (–8 hrs) | NTS Area U2di 37.12447°N 116.08798°W | 1,280 m (4,200 ft) – 330.71 m (1,085.0 ft) | underground shaft, weapons development | less than 20 kt | [1][3][4] | |||
| Cathay | October 8, 1971 14:30:00.15 | PST (–8 hrs) | NTS Area U9ch 37.11373°N 116.0382°W | 1,261 m (4,137 ft) – 377.95 m (1,240.0 ft) | underground shaft, weapons development | 7 kt | [1][3][4][7][8] | |||
| Lagoon | October 14, 1971 14:30:00.16 | PST (–8 hrs) | NTS Area U10ar 37.17987°N 116.05396°W | 1,286 m (4,219 ft) – 304.8 m (1,000 ft) | underground shaft, weapons development | 5 kt | [1][3][4] | |||
| Cannikin | November 6, 1971 22:00:00.06 | BST (–11 hrs) | Amchitka Island, Alaska 51.4699°N 179.10671°E | 63 m (207 ft) – 1,790 m (5,870 ft) | underground shaft, weapons development | 4.8 Mt | [1][4][7] | A test of the Spartan ABM warhead. The largest underground nuclear test ever. | ||
| Diagonal Line | November 24, 1971 20:15:00.17 | PST (–8 hrs) | NTS Area U11g 36.8793°N 115.93587°W | 1,010 m (3,310 ft) – 264.26 m (867.0 ft) | underground shaft, weapon effect | 4 kt | Venting detected off site, 6.8 kCi (250 TBq) | [1][3][4][5][6][7] | Picture of the "Ship of the Desert", a structure for capturing neutrons for experiments with this test: File:NNSA-NSO-1347.jpg. | |
| Parnassia | November 30, 1971 15:45:00.15 | PST (–8 hrs) | NTS Area U2bc 37.16045°N 116.07112°W | 1,302 m (4,272 ft) – 330.71 m (1,085.0 ft) | underground shaft, weapons development | 10 kt | [1][3][4] | |||
| Chaenactis | December 14, 1971 21:09:59.16 | PST (–8 hrs) | NTS Area U2dl 37.12393°N 116.09049°W | 1,281 m (4,203 ft) – 331.01 m (1,086.0 ft) | underground shaft, weapons development | 24 kt | [1][3][4][7][8] | |||
| Hospah | December 14, 1971 21:10:01.04 | PST (–8 hrs) | NTS Area U3je 37.02584°N 116.02992°W | 1,188 m (3,898 ft) – 302.03 m (990.9 ft) | underground shaft, weapons development | 11 kt | [1][3][4] | |||
| Yerba | December 14, 1971 21:10:01.04 | PST (–8 hrs) | NTS Area U1c 37.02317°N 116.05957°W | 1,202 m (3,944 ft) – 331.99 m (1,089.2 ft) | underground shaft, weapons development | 5 kt | [1][3][4] | |||
| Mescalero | January 5, 1972 15:10:00.04 | PST (–8 hrs) | NTS Area U3gu 37.04565°N 116.03032°W | 1,198 m (3,930 ft) – 120.24 m (394.5 ft) | underground shaft, weapons development | less than 20 kt | [1][3][4] | |||
| Cowles | February 3, 1972 21:45:00.04 | PST (–8 hrs) | NTS Area U3hx 37.00105°N 116.02016°W | 1,178 m (3,865 ft) – 301.78 m (990.1 ft) | underground shaft, weapons development | 2 kt | [1][3][4][8][10] | |||
| Dianthus | February 17, 1972 19:02:00.16 | PST (–8 hrs) | NTS Area U10at 37.16566°N 116.05711°W | 1,279 m (4,196 ft) – 304.8 m (1,000 ft) | underground shaft, weapons development | 3.5 kt | Venting detected, 18 Ci (670 GBq) | [1][3][4][6][8] | ||
| Sappho | March 23, 1972 18:50:00.16 | PST (–8 hrs) | NTS Area U2dh2 37.113°N 116.08169°W | 1,266 m (4,154 ft) – 197.82 m (649.0 ft) | underground shaft, weapons development | 4 kt | Venting detected, 9 Ci (330 GBq) | [1][3][4][6][10] | ||
| Ocate – 2 (with Onaja) | March 30, 1972 21:00:00.08 | PST (–8 hrs) | NTS Area U3jp 37.00449°N 116.01565°W | 1,179 m (3,868 ft) + | underground shaft, weapons development | less than 20 kt | [1][3][4] | |||
| Onaja – 1 (with Ocate) | March 30, 1972 21:00:00.04 | PST (–8 hrs) | NTS Area U3js 37.0055°N 116.02078°W | 1,180 m (3,870 ft) – 279.04 m (915.5 ft) | underground shaft, weapons development | 8 kt | [1][3][4] | |||
| Longchamps | April 19, 1972 16:32:00.16 | PST (–8 hrs) | NTS Area U2dm 37.12204°N 116.08486°W | 1,276 m (4,186 ft) – 326.44 m (1,071.0 ft) | underground shaft, weapons development | 8 kt | [1][3][4][7] | |||
| Jicarilla | April 19, 1972 16:42:00.05 | PST (–8 hrs) | NTS Area U3jm 37.00661°N 116.01734°W | 1,180 m (3,870 ft) – 148.11 m (485.9 ft) | underground shaft, weapons development | less than 20 kt | [1][3][4] | |||
| Misty North | May 2, 1972 19:15:00.04 | PST (–8 hrs) | NTS Area U12n.05 37.20762°N 116.20963°W | 2,199 m (7,215 ft) – 376.08 m (1,233.9 ft) | tunnel, weapon effect | 19 kt | [1][3][4][8][9] | |||
| Kara | May 11, 1972 14:00:00.16 | PST (–8 hrs) | NTS Area U2dh3 37.11247°N 116.08525°W | 1,267 m (4,157 ft) – 259.08 m (850.0 ft) | underground shaft, weapons development | 500 t | Venting detected, 7 Ci (260 GBq) | [1][3][4][6][8] | ||
| Zinnia | May 17, 1972 14:10:00.16 | PST (–8 hrs) | NTS Area U2dk 37.12056°N 116.08883°W | 1,277 m (4,190 ft) – 322.78 m (1,059.0 ft) | underground shaft, weapons development | 8 kt | Venting detected, 7 Ci (260 GBq) | [1][3][4][5][7][8] | ||
| Monero | May 19, 1972 17:00:00.05 | PST (–8 hrs) | NTS Area U3jg 37.06469°N 116.0025°W | 1,245 m (4,085 ft) – 537.35 m (1,763.0 ft) | underground shaft, weapons development | 12 kt | [1][3][4][9] | |||
| Merida | June 7, 1972 15:20:00.16 | PST (–8 hrs) | NTS Area U2dn 37.11579°N 116.08619°W | 1,271 m (4,170 ft) – 204.22 m (670.0 ft) | underground shaft, weapons development | 800 t | Venting detected, 10 Ci (370 GBq) | [1][3][4][6][8] | ||
| Capitan | June 28, 1972 14:41:00.19 | PST (–8 hrs) | NTS Area U3jj 36.99256°N 116.02302°W | 1,175 m (3,855 ft) – 134.48 m (441.2 ft) | underground shaft, weapons development | 600 t | [1][3][4][8] | |||
| Tajique | June 28, 1972 16:30:00.07 | PST (–8 hrs) | NTS Area U7aa 37.06958°N 115.99286°W | 1,274 m (4,180 ft) – 332.31 m (1,090.3 ft) | underground shaft, weapons development | less than 20 kt | [1][3][4] | |||
| Haplopappus | June 28, 1972 16:30:03.16 | PST (–8 hrs) | NTS Area U9itsw22 37.13515°N 116.03614°W | 1,264 m (4,147 ft) – 184.4 m (605 ft) | underground shaft, weapons development | 6 kt | [1][3][4] |
- A bomb test may be a salvo test, defined as two or more explosions "where a period of time between successive individual explosions does not exceed 5 seconds and where the burial points of all explosive devices can be connected by segments of straight lines, each of them connecting two burial points and does not exceed 40 kilometers in length". Mikhailov, V. N. "Catalog of World Wide Nuclear Testing". Begell-Atom. Archived from the original on April 26, 2014.
- 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.
- 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.
- 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.
- 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.
- 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.
- Include weapons development, weapon effects, safety test, transport safety test, war, science, joint verification and industrial/peaceful, which may be further broken down.
- 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.
- Estimated energy yield in tons, kilotons, and megatons. A ton of TNT equivalent is defined as 4.184 gigajoules (1 gigacalorie).
- 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.
Remove ads
Wikiwand in your browser!
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.
Remove ads