Operation Hardtack II
| Operation Hardtack II | |
|---|---|
 Hardtack II Sanford, 4.9 kilotons. | |
| Information | |
| Country | United States |
| Test site |
|
| Period | 1958 |
| Number of tests | 37 |
| Test type | balloon, dry surface, tower, underground shaft, tunnel |
| Max. yield | 22kilotonnes of TNT(92 TJ) |
| Test series chronology | |
Operation Hardtack II[1]was a series of 37nuclear testsconducted by the United States in 1958 at theNevada Test Site.These tests followed theOperation Argusseries and preceded theOperation Nougatseries.
With test moratoriums on the horizon, American weapons labs rushed out many new designs. A hard deadline for testing was set at midnight (0000 hrs), October 31, 1958, as negotiations were set to start that day, and the schedule shows it, with 29 tests executed in October, four of them on the last day. One other test was cancelled because weather delays postponed it across the midnight deadline. After the conclusion of Hardtack II, the United States announced a unilateral testing moratorium, which the Soviet Union joined after two last tests on November 1 and 3.[2]In September 1961, the Soviet Union resumed nuclear testing — including the test of the most powerful nuclear device ever designed, theTsar Bomba,in October — and the United States followed suit withOperation Nougat.
Nuclear tests[edit]
Adams[edit]
Adams was planned to be the final test of Hardtack II, but due to unfavorable winds the shot was never fired. The shot was intended to be a balloon test, and had been fully assembled and raised to firing altitude when it was cancelled. After midnight and the start of the moratorium, the device was lowered to the ground and disassembled. The Soviet Union would continue nuclear testing until the 3rd of November.[3]
A 31st October 1958 meeting of the Atomic Energy Commission following the cancellation resulted in the following note:[4]
[General Alfred Starbird] said there will always be a question as to whether the final shot should have been fired in view of its importance [redacted] but he believed that the other considerations were of overriding importance.
List of nuclear tests[edit]
| Name[note 1] | Date time (UT) | Localtime 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Otero | September 12, 195820:00:00.2 | PST (–8 hrs) | NTSArea U3q37°02′59″N116°01′57″W/ 37.04985°N 116.03255°W | 1,229 m (4,032 ft)–150 m (490 ft) | underground shaft, safety experiment |
XW-54? | 38 t | Venting detected, 6 kCi (220 TBq) | [1][6][7][8] | 1-point test,failed, device similar toHT-I Sequoia. |
| Bernalillo | September 17, 195819:30:00.2 | PST (–8 hrs) | NTSArea U3h (n?)37°02′58″N116°02′01″W/ 37.04944°N 116.03352°W | 1,229 m (4,032 ft)–150 m (490 ft) | underground shaft, safety experiment |
XW-54 | 15 t | Venting detected on site | [1][6][8] | 1-point test, repeat ofOtero,also failed. |
| Eddy | September 19, 195814:00:00.2 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 150 m (490 ft) | balloon, weapons development |
83 t | Venting detected, 12 kCi (440 TBq) | [1][6][8] | 154 pounds (70 kg) test device successful. | |
| Luna | September 21, 195819:00:00.2 | PST (–8 hrs) | NTSArea U3m37°02′57″N116°02′04″W/ 37.04919°N 116.03447°W | 1,230 m (4,040 ft)–150 m (490 ft) | underground shaft, safety experiment |
XW-54? | 1.5 t | Venting detected on site | [1][6][7][8] | 1-point test, repeat ofOtero/Bernalillo,still unsafe. |
| Mercury | September 23, 195822:00:00.0 | PST (–8 hrs) | NTSArea U12f.0137°11′34″N116°12′01″W/ 37.19274°N 116.20024°W | 2,038 m (6,686 ft)–55.78 m (183.0 ft) | tunnel, safety experiment |
XW-47primary? | 10 t | [1][6][7][8][9] | 1-point test, declared success despite yield, XW-42 test, similar toPascal-CandSan Juandevices. | |
| Valencia | September 26, 195820:00:00.2 | PST (–8 hrs) | NTSArea U3r37°02′58″N116°01′50″W/ 37.04956°N 116.03057°W | 1,227 m (4,026 ft)–150 m (490 ft) | underground shaft, safety experiment |
XW-42? | 2 t | Venting detected on site | [1][6][7][8] | 1-point test, declared success despite yield, similar toPascal-CandSan Juandevices. |
| Mars | September 28, 195800:00:00.2 | PST (–8 hrs) | NTSArea U12f.0237°11′35″N116°12′05″W/ 37.19301°N 116.20131°W | 2,082 m (6,831 ft)–42.67 m (140.0 ft) | tunnel, safety experiment |
XW-48 | 13 t | Venting detected on site | [1][6][7][8][9] | 1-point test, similar toTamalpaisandCeres. |
| Mora | September 29, 195814:05:00.1 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 460 m (1,510 ft) | balloon, weapons development |
XW-54Gnat | 2 kt | Venting detected, 340 kCi (13,000 TBq) | [1][6][8] | Full yield test of device similar toOteroet al., fizzled. |
| Hidalgo | October 5, 195814:10:00.1 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 110 m (360 ft) | balloon, safety experiment |
Moccasin | 77 t | Venting detected, 11 kCi (410 TBq) | [1][6][8] | This 1-point test failed; similar toCoulomb-C. |
| Colfax | October 5, 195816:15:00.2 | PST (–8 hrs) | NTSArea U3k37°02′56″N116°02′06″W/ 37.04882°N 116.03491°W | 1,229 m (4,032 ft)–107 m (351 ft) | underground shaft, safety experiment |
XW-54Gnat | 5.5 t | Venting detected, 240 kCi (8,900 TBq) | [1][6][8] | 1-point test of device similar toOteroet al., failed. Unstemmed shaft. |
| Tamalpais | October 8, 195822:00:00.13 | PST (–8 hrs) | NTSArea U12b.0237°11′43″N116°12′05″W/ 37.19525°N 116.20133°W | 2,152 m (7,060 ft)–124.05 m (407.0 ft) | tunnel, weapons development |
XW-48 | 72 t | [1][6][7][8][9] | Full yield test, similar toMarsandCeres. | |
| Quay | October 10, 195814:30:00.1 | PST (–8 hrs) | NTSArea 7c37°05′41″N116°01′28″W/ 37.0947°N 116.0245°W | 1,294 m (4,245 ft) + 30 m (98 ft) | tower, weapons development |
XW-50? | 79 t | Venting detected, 200 Ci (7,400 GBq) | [1][6][7][8] | Concept feasibility test, similar toHT-I Linden. |
| Lea | October 13, 195813:20:00.1 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 460 m (1,510 ft) | balloon, weapons development |
XW-54Gnat? | 1.4 kt | Venting detected, 240 kCi (8,900 TBq) | [1][6][7][8][10] | Full yield test of device similar toOteroet al., fizzled. |
| Neptune | October 14, 195818:00:00.2 | PST (–8 hrs) | NTSArea U12c.0337°11′38″N116°12′02″W/ 37.19381°N 116.20057°W | 2,080 m (6,820 ft)–30.02 m (98.5 ft) | tunnel, safety experiment |
XW-47 | 115 t | Venting detected on site | [1][6][8][9] | 1-point test, failed, similar toHT-I HickoryandHT-II Titania.First NTS subsidence crater at Rainier despite low yield and depth buried. |
| Hamilton | October 15, 195816:00:00.2 | PST (–8 hrs) | NTSArea 536°48′08″N115°55′59″W/ 36.8022°N 115.9331°W | 940 m (3,080 ft) + 15 m (49 ft) | tower, weapons development |
XW-51?Quail | 1.2 t | Venting detected, 200 Ci (7,400 GBq) | [1][6][7][8] | Davy Crockettprototype test, fizzled, extremely small device (16 kg (35 lb)). |
| Logan | October 16, 195806:00:00.14 | PST (–8 hrs) | NTSArea A12e.0237°11′02″N116°12′07″W/ 37.18399°N 116.20206°W | 2,155 m (7,070 ft)–283.58 m (930.4 ft) | tunnel, weapons development |
5 kt | [1][6][8][9] | ABM warhead test, small (28.6 kg (63 lb), 28 cm × 29 cm (11 in × 11 in)) kiloton-range device, successful. | ||
| Dona Ana | October 16, 195814:20:00.1 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 150 m (490 ft) | balloon, weapons development |
XW-54Gnat | 37 t | Venting detected, 6 kCi (220 TBq) | [1][6][8] | Low yield test, similar to Otero et al. |
| Vesta | October 17, 195823:00:00.2 | PST (–8 hrs) | NTSArea S9e37°07′21″N116°02′05″W/ 37.1226°N 116.0347°W | 1,294 m (4,245 ft) + 0 | dry surface, safety experiment |
XW-47primary | 24 t | Venting detected, 4 kCi (150 TBq) | [1][6][7][8] | 1-point test, failed, similar toWrangell, Oberon, Sanford. |
| Rio Arriba | October 18, 195814:25:00.1 | PST (–8 hrs) | NTSArea 3s37°02′28″N116°01′36″W/ 37.0411°N 116.0267°W | 1,224 m (4,016 ft) + 20 m (66 ft) | tower, weapons development |
Mk-7 | 90 t | Venting detected, 120 kCi (4,400 TBq) | [1][6][7][8] | Low yield Mk-7, successful, fired on wooden tower. |
| San Juan | October 20, 195814:30:00.2 | PST (–8 hrs) | NTSArea U3p37°02′59″N116°02′00″W/ 37.04976°N 116.03325°W | 1,229 m (4,032 ft)–71 m (233 ft) | underground shaft, safety experiment |
XW-42? | no yield | [1][6][7][8] | 1-point test, successful, safe design extrapolated fromPascal-CandHT-II Valencia.Unstemmed shaft. | |
| Socorro | October 22, 195813:30:00.2 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 440 m (1,440 ft) | balloon, weapons development |
XW-54Gnat? | 6 kt | Venting detected, 1,000 kCi (37,000 TBq) | [1][6][7][8][10] | Full yield test of XW-54 primary, successful, similar toOteroet al. |
| Wrangell | October 22, 195816:50:00.1 | PST (–8 hrs) | NTSArea 536°47′53″N115°55′47″W/ 36.798°N 115.9298°W | 940 m (3,080 ft) + 460 m (1,510 ft) | balloon, weapons development |
XW-47Canary? | 115 t | Venting detected, 17 kCi (630 TBq) | [1][6][7][8] | Full yield test fizzle, similar toVesta, Oberon, Sanford. |
| Oberon | October 22, 195820:30:?? | PST (–8 hrs) | NTSArea 8a37°10′58″N116°04′09″W/ 37.1829°N 116.0691°W | 1,355 m (4,446 ft) + 8 m (26 ft) | tower, safety experiment |
XW-47primary Canary? | no yield | Venting detected, 17 kCi (630 TBq) | [1][6][7][8][11] | 1-point test, successful, similar toVesta, Wrangell, Sanford. |
| Rushmore | October 22, 195823:40:00.1 | PST (–8 hrs) | NTSArea B9a ~37°08′05″N116°02′30″W/ 37.1347°N 116.0417°W | 1,285 m (4,216 ft) + 150 m (490 ft) | balloon, weapons development |
XW-47primary Canary? | 188 t | [1][6][7][8] | Low yield test, fizzled, similar toMercury, Neptune, Titania. | |
| Catron | October 24, 195815:00:00.2 | PST (–8 hrs) | NTSArea 3t37°02′34″N116°01′40″W/ 37.0427°N 116.0277°W | 1,225 m (4,019 ft) + 20 m (66 ft) | tower, safety experiment |
XW-54Gnat | 21 t | Venting detected, 4 kCi (150 TBq) | [1][6][8] | 1-point test, similar toMora,failed, fired on wooden tower. |
| Juno | October 24, 195816:01:00.2 | PST (–8 hrs) | NTSArea S9f37°07′25″N116°02′16″W/ 37.12361°N 116.03776°W | 1,287 m (4,222 ft) + 0 | dry surface, safety experiment |
Logan | 1.7 t | [1][6][7][8] | 1-point test to determine safety limits. | |
| Ceres | October 26, 195804:00:00.2 | PST (–8 hrs) | NTSArea 8b37°10′53″N116°04′09″W/ 37.1814°N 116.0691°W | 1,350 m (4,430 ft) + 10 m (33 ft) | tower, safety experiment |
XW-48AFAP | 700 kg | [1][6][7][8] | 1-point test of atomic artillery shell, similar toTamalpaisandMars. | |
| Sanford | October 26, 195810:20:00.1 | PST (–8 hrs) | NTSArea 536°47′53″N115°55′47″W/ 36.798°N 115.9298°W | 940 m (3,080 ft) + 460 m (1,510 ft) | balloon, weapons development |
XW-47primary Canary? | 4.9 kt | Venting detected, 750 kCi (28,000 TBq) | [1][6][7][8] | Full yield test, successful, similar toVesta, Oberon, Wrangell. |
| De Baca | October 26, 195816:00:00.1 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 460 m (1,510 ft) | balloon, weapons development |
XW-54Gnat | 2.2 kt | Venting detected, 380 kCi (14,000 TBq) | [1][6][8][10] | Full yield test, disappointing yield, similar to CatronandMora. |
| Chavez | October 27, 195814:30:?? | PST (–8 hrs) | NTSArea 3u37°02′39″N116°01′50″W/ 37.0443°N 116.0305°W | 1,225 m (4,019 ft) + 16 m (52 ft) | tower, safety experiment |
XW-54Gnat | 600 kg | Venting detected, 100 Ci (3,700 GBq) | [1][6][7][8][11] | 1-point test of device similar toDe Baca,failed, fired on wooden tower. |
| Evans | October 29, 195800:00:00.15 | PST (–8 hrs) | NTSArea U12b.0437°11′41″N116°12′20″W/ 37.19477°N 116.20563°W | 2,282 m (7,487 ft)–256.03 m (840.0 ft) | tunnel, weapons development |
XW-47primary Canary? | 55 t | Venting detected on site | [1][6][7][8][9] | Full yield test fizzle, similar toBlanca. |
| Mazama | October 29, 195811:20:?? | PST (–8 hrs) | NTSArea 937°07′35″N116°02′31″W/ 37.12648°N 116.04196°W | 1,282 m (4,206 ft) + 15 m (49 ft) | tower, weapons development |
no yield | [1][6][7][8][11] | Fizzle. | ||
| Humboldt | October 29, 195814:45:00.1 | PST (–8 hrs) | NTSArea 3v37°02′52″N116°01′32″W/ 37.0477°N 116.0256°W | 1,228 m (4,029 ft) + 10 m (33 ft) | tower, weapons development |
XW-51? | 7.8 t | Venting detected, 1 kCi (37 TBq) | [1][6][7][8] | Repeat ofHamiltonwith higher yield, extremely small device (16 kg). |
| Santa Fe | October 30, 195803:00:00.1 | PST (–8 hrs) | NTSArea B7b ~37°05′12″N116°01′28″W/ 37.0866°N 116.0245°W | 1,282 m (4,206 ft) + 460 m (1,510 ft) | balloon, weapons development |
XW-54Gnat | 1.3 kt | Venting detected, 220 kCi (8,100 TBq) | [1][6][8][10] | Similar to devices fired in many preceding shots, yield below predictions. |
| Ganymede | October 30, 195811:00:?? | PST (–8 hrs) | NTSArea S9g37°07′23″N116°02′06″W/ 37.123°N 116.035°W | 1,294 m (4,245 ft) + 0 | dry surface, safety experiment |
W-45 | no yield | [1][6][7][8][11] | 1-point test of W-45/Swan variant, successful. | |
| Blanca | October 30, 195815:00:00.15 | PST (–8 hrs) | NTSArea U12e.0537°11′09″N116°12′10″W/ 37.18589°N 116.20289°W | 2,168 m (7,113 ft)–254.51 m (835.0 ft) | tunnel, weapons development |
XW-47primary Canary | 22 kt | Venting detected, 510 Ci (19,000 GBq) | [1][6][7][8][9][10] | Test of alternate W-47 primary in TN mockup, successful, similar toEvans,shot vented to atmosphere through the side of the mesa. |
| Titania | October 30, 195820:34:00.2 | PST (–8 hrs) | NTSArea 8c37°10′38″N116°04′12″W/ 37.1773°N 116.0699°W | 1,343 m (4,406 ft) + 10 m (33 ft) | tower, safety experiment |
XW-47primary Canary | 200 kg | [1][6][7][8] | 1-point test of original XW-47 primary, declared safe despite yield, similar toHT-I HickoryandHT-II Neptune. | |
| Adams (canceled) |
October 31, 1958 | PST (–8 hrs) | NTS~37°02′38″N116°04′05″W/ 37.044°N 116.068°W | 1,220 m (4,000 ft) +??? | Balloon, weapons development |
unknown yield | Test planned forHardtack II,but held up by atmospherics that would have shattered windows in Las Vegas, and could not be completed in time before start of moratorium negotiations. |
- ^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 theIANA 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 thePartial 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 intons, 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.
References[edit]
- ^abcdefghijklmnopqrstuvwxyzaaabacadaeafagahaiajakalYang, Xiaoping; North, Robert; Romney, Carl (August 2000),CMR Nuclear Explosion Database (Revision 3),SMDC Monitoring Research
- ^"Gallery of U.S. Nuclear Tests".
- ^Meade, Roger Allen (September 12, 2022).Hardtack II(Report). Los Alamos National Lab. (LANL), Los Alamos, NM (United States).RetrievedJanuary 23,2024.
- ^William E Ogle (October 1985).An Account of the Return to Nuclear Weapons Testing by the United States After the Test Moratorium 1958-1961(Report). US Department of Energy (USDOE), Nevada Operations Office. p. 107-108.RetrievedJuly 16,2021.
- ^"Time Zone Historical Database".iana.RetrievedMarch 8,2014.
- ^abcdefghijklmnopqrstuvwxyzaaabacadaeafagahaiajakEstimated 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,retrievedJanuary 5,2014
- ^abcdefghijklmnopqrstuvwxyzHansen, Chuck (1995),The Swords of Armageddon, Vol. 8,Sunnyvale, CA: Chukelea Publications,ISBN978-0-9791915-1-0
- ^abcdefghijklmnopqrstuvwxyzaaabacadaeafagahaiajakUnited 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 fromthe original(PDF)on October 12, 2006,retrievedDecember 18,2013
- ^abcdefgOfficial list of underground nuclear explosions,Sandia National Laboratories, July 1, 1994,retrievedDecember 18,2013
- ^abcdeSublette, Carey,Nuclear Weapons Archive,retrievedJanuary 6,2014
- ^abcdOperation Hardtack II, 1958(PDF)(DNA6026F), Defense Nuclear Agency, Department of Defense (Washington, DC), archived fromthe original(PDF)on February 18, 2013,retrievedOctober 31,2013
External links[edit]
- The short filmOperation HARDTACK Military Effects Studies Part I: Basic Effects Structures and Materiel (1958)is available for free viewing and download at theInternet Archive.
- The short filmOperation HARDTACK Military Effects Studies Part II: Underwater Tests (1958)is available for free viewing and download at theInternet Archive.
- The short filmOperation HARDTACK Military Effects Studies Part III: High Altitude Tests (1958)is available for free viewing and download at theInternet Archive.
- The short filmOperation HARDTACK Military Effects Studies: Part IV - Sub-kiloton effectsis available for free viewing and download at theInternet Archive.
