| In it closing days, the Eisenhower administration initiated negotitations on a nuclear test ban with the Soviet Union (this intention was announced by Eisenhower on 22 August 1958). As an important confidence building measure, Eisenhower also announced a one-year voluntary moratorium on nuclear testing (if the Soviets made a reciprocal commitment) would go into effect on 31 October 1958. This ban was later extended to 13 months (31 December 1959), but on 29 December 1959 the U.S. announced an end to the voluntary moratorium although it also promised not the renew testing without advance public notice. This decision not the extend the formal moratorium commitment may have been due to the status of the negotiations, which were faring very poorly. On 3 January 1960, Khrushchev pledged that the Soviet Union would not conduct nuclear testing unless the Western nations resumed it. The US, the UK and France made no move to resume testing, and so the matter rested for nearly three years. On 31 August 1961, Khrushchev announced that the Soviet Union was abruptly abandoning the prevailing de facto nuclear testing moratorium, which they (and the United States) had observed for 34 months. The next day, on 1 September 1961, the Soviet Union began an atmospheric test series of unprecedented magnitude with a 16 Kt atmospheric nuclear shot. Two weeks later, the U.S. responded by initiating Operation Nougat. This series was conducted at the Nevada Test Site, which permitted rapid initiation of tests, but restricted them to low yields (and mostly underground test shots) due to fallout concerns. Although this was still the "era of atmospheric testing", Nougat was actually the first underground test series. Higher yield atmospheric tests followed seven months later with Operation Dominic in the Pacific. The assignment of tests to individual "operations" between this time and the end of atmospheric testing is confused and complicated by several overlapping operations - Nougat, Dominic (or Dominic I), Sunbeam (or Dominic II), Fishbowl, Storax, and Roller Coaster. The available documentation on these operations is somewhat unclear unclear or confusing, and it may be that in some cases a shot may be officially included in more than one operation. Definitely and unambiguously assigning shots to operations for this period is thus hard or impossible. Some disagreement about which shots should be properly included with a particular operation may occur. According to this account Operation Nougat included a total of 44 shots, exceeding the previous record holder, Operation Hardtack II, with 37 tests. Nougat generally resembles Hardtack II in the nature of testing that was conducted. Low yield tactical devices were extensively tested. Thermonuclear primaries and radiation imploson mockups were tested. Much attention was paid to simultaneously achieving desired performance and one-point safety in "sealed pit" fission devices, some designs requiring numerous shots. |
Since all the tests were fired underground, and only a few of them produced true blast craters (i.e. not subsidence craters caused by blast cavity collapse), there are few pictures available of these tests.
The one test for which any relevant images are available is much publicized Gnome shot.
| Test: | Gnome |
|---|---|
| Time: | 12:10 10 December 1961 (GMT) |
| Location: | Carlsbad, NM |
| Test Height and Type: | Shaft Shot, -1184 ft |
| Yield: | 3.1 kt |
This Plowshare shot, conducted by Lawrence Radiation Laboratory (later Lawrence Livermore), was fired in an underground salt dome formation. A permanent stable cavity 170 ft. in diameter, and 80 ft. high, was formed. This one of the very few nuclear test cavities (perhaps the only one) to avoid collapse. Some radiation accidentally released as a result of pot shot drilling, and detected off-site.
 547x412, 67K |
| Gnome cavity |
 1024x1119, 87K |
| Gnome diagram |
Legend:WD=Weapons Development, WE=Weapons Effects, ST=Safety Test, TN= Thermonuclear, LASL=Los Alamos Scientific Laboratory, LRL=Lawrence Radiation Laboratory (later Lawrence Livermore), DOD=Department of Defense, PS=Plowshare, sim.=similar, proto.=prototype, Zipper=neutron initiator,
| Test Name | Time and Date (GMT) | Location | Test Type | Height (Ft) | Yield (Kt) | Sponsor | Purpose | Comments |
|---|---|---|---|---|---|---|---|---|
| Antler | 17:00.00.12 15-Sep-61 | NTS, Area 12e | Tunnel | -1,318 | 2.6 | LRL | WD | Possible W-45 test, yield slightly higher than expected |
| Shrew | 19:45.00.12 16-Sep-61 | NTS, Area 3ac | Shaft | -322 | 0.017 | LASL | WD | Possible XW-54 test, performed as expected |
| Boomer | 22:00 1-Oct-61 | NTS, Area 3aa | Shaft | -330 | <0.1 | LASL | WD | Possible XW-54 test, performed as expected |
| Chena | 18:00.00.12 10-Oct-61 | NTS, Area 12b | Tunnel | -838 | <20 | LRL | WD | Arrow device, possible W-44 proto., sim. to D-I Swordfish, yield much lower than pred. |
| Mink | 18:00.00.13 29-Oct-61 | NTS, Area 3ae | Shaft | -630 | <20 | LASL | WD | Sim. to HT-II Quay, HT-I Linden, fizzle |
| Fisher | 23:04.59.63 3-Dec-61 | NTS, Area 3ah | Shaft | -1191 | 13.4 | LASL | WD | Repeat of Mink, possible XW-50 primary test, yield below pred. due to Zipper failure |
| Gnome | 19:00.00.00 10-Dec-61 | Carlsbad, NM | Shaft | -1184 | 3.1 | LRL | PS | Plowshare shot, fired in salt dome, cavity formed was 170 ft. in diameter, and 80 ft. high, some radiation accidentally released and detected off-site |
| Mad | 18:00.00.16 13-Dec-61 | NTS, Area 9a | Shaft | -594 | 0.5 | LASL | WD | Sim. to Hoosic and Stillwater, yield below pred., attempt to standardize low yield energy source for future experiments |
| Ringtail | 16:35.00.13 17-Dec-61 | NTS, Area 3ak | Shaft | -1,192 | <20 | LRL | WD | Possible XW-54 test, sim. to Shrew and Boomer, purpose to optimize small light system for high yield tactical weapon |
| Feather | 16:30.00.13 22-Dec-61 | NTS, Area 12b | Tunnel | -812 | 0.15 | LRL | WD | "...results quite striking." |
| Stoat | 16:30.00.14 9-Jan-62 | NTS, Area 3ap | Shaft | -992 | 5.1 | LASL | WD | Performed as expected, 1st in series to develop new multi-point detonation system, sim. to Agouti, Armadillo, Ermine, Chinchilla I/II |
| Agouti | 18:00.00.13 18-Jan-62 | NTS, Area 3ao | Shaft | -856 | 6.4 | LASL | WD | Develop test for new 10 inch implosion system, sim. Stoat |
| Dormouse | 18:00.00.13 30-Jan-62 | NTS, Area 3aq | Shaft | -1191 | <20 | LASL | WD | Configuration optimization test, sim. to Mink, Fisher, Raccoon, Dormouse Prime, Packrat |
| Stillwater | 18:00.00.16 8-Feb-62 | NTS, Area 9c | Shaft | -595 | 3.07 | LRL | WD | Similar to Mad and Hoosic |
| Armadillo | 16:30.00.13 9-Feb-62 | NTS, Area 3ar | Shaft | -786 | 7.1 | LASL | WD | Develop test for new 10 inch implosion system, sim. Stoat |
| Hardhat | 18:00.10.16 15-Feb-62 | NTS, Area 15a | Shaft | -943 | 5.7 | DOD | WE | Test of underground structure hardening |
| Chinchilla I | 16:30.00.13 19-Feb-62 | NTS, Area 3ag | Shaft | -492 | 1.9 | LASL | WD | Test of new 10" implosion system, performed as expected, showed device not 1-point safe |
| Codsaw | 17:50.00.16 19-Feb-62 | NTS, Area 9g | Shaft | -696 | <20 | LRL | WD | Possible W-45 test, sim. to Hoosic, Hudson, Arikaree |
| Cimarron | 18:00.00.16 23-Feb-62 | NTS, Area 9h | Shaft | -1000 | 11.9 | LRL | WD | Confirmed advanced warhead design, device performed better than expected |
| Platypus | 16:30.00.13 24-Feb-62 | NTS, Area 3ad | Shaft | -190 | <20 | LASL | WD | Sim. to Shrew, Boomer, Ringtail |
| Pampas | 19:10.00.09 1-Mar-62 | NTS, Area 3al | Shaft | -1191 | 9.5 | LASL/UK | WD | First joint Us-UK test at NTS |
| Danny Boy | 18:15.00.12 5-Mar-62 | NTS, Area 18 | Subsurface | -110 | 0.43 | DOD/LRL | WE | Test of atomic demolition munition (ADM) cratering effects in basalt, crater 265' by 84', design yield 470 tons |
| Ermine | 16:30.00.13 6-Mar-62 | NTS, Area 3ab | Shaft | -240 | <20 | LASL | ST | Test of new 10" implosion system, 1-point safety test |
| Brazos | 18:00.00.21 8-Mar-62 | NTS, Area 9b | Shaft | -841 | 8.4 | LRL | WD | Successful system proof test, possible XW-55 primary test, developmental test of advanced implosion system, design yield 5-10 Kt |
| Hognose | 16:30.00.13 15-Mar-62 | NTS, Area 3ai | Shaft | -784 | <20 | LASL | WD | Sim. to Ht-II Mercury and Oberon |
| Hoosic | 18:00.00.16 28-Mar-62 | NTS, Area 9j | Shaft | -614 | 3.4 | LRL | WD | Test to determine minimum boosted yield for device previously tested in Mad and Stillwater, possible XW-45 test, pred. yield 2-3.5 Kt, sim. to Hudson and Arikaree |
| Chinchilla II | 18:00.00.13 31-Mar-62 | "NTS, Area 3as" | Shaft | -448 | <20 | LASL | WD | Retest of Chinchilla I which was not 1-point safe, sim. to Stoat |
| Dormouse Prime | 18:00.00.13 5-Apr-62 | NTS, Area 3az | Shaft | -856 | 10.6 | LASL | WD | Yield verification test, design yield 10.5 Kt, boron lined shot hole, sim. to Dormouse, Mink, Fisher, Raccoon, Packrat, HT-I Linden, HT-II Quay |
| Passaic | 18:00.00.16 6-Apr-62 | NTS, Area 9i | Shaft | -766 | <20 | LRL | WD | Verification test |
| Hudson | 18:00.00.16 12-Apr-62 | NTS, Area 9h | Shaft | -495 | <20 | LRL | WD | Sim. to Arikaree, Hoosic, Codsaw; possible W-45 test |
| Platte | 18:00.00.13 14-Apr-62 | NTS, Area 12k | Tunnel | -628 | 1.85 | LRL | WD | Yield reproducibility test, failed, retested in Des Moines |
| Dead | 18:40.00.16 21-Apr-62 | NTS, Area 9k | Shaft | -634 | <20 | LRL | WD | |
| Black | 18:00.00.16 27-Apr-62 | NTS, Area 9p | Shaft | -714 | <20 | LRL | WD | XW-55 primary in TN mockup |
| Paca | 19:33.00.0 7-May-62 | NTS, Area 3ax | Shaft | -848 | <20 | LASL | WD | Test of "100 lb/100 Kt" class device |
| Arikaree | 15:00 10-May-62 | NTS | Shaft | -549 | <20 | LRL | WD | Sim. to Hudson, Hoosic, Codsaw; possible W-45 test |
| Aardvark | 19:00.00.10 12-May-62 | NTS, Area 3 | Shaft | -1424 | 40 | LASL | WD | Test of improved TX-33Y2 AFAP |
| Eel | 15:00.00.16 19-May-62 | NTS, Area 9m | Shaft | -714 | 4.9 | LRL | WD | Successful |
| White | 15:00.00.15 25-May-62 | NTS, Area 9b | Shaft | -635 | <20 | LRL | WD | Probable XW-58 primary test, sim. to Sacramento |
| Racoon | 17:00.00.14 1-Jun-62 | NTS, Area 3a | Shaft | -539 | <20 | LASL | WD | Successful, sim. to Dormouse, Dormouse Prime, Mink, Fisher, Packrat, HT-I Linden, HT-II Quay |
| Packrat | 17:00.00.12 6-Jun-62 | NTS, Area 3aw | Shaft | -860 | <20 | LASL | WD | Successful (see above for similarities), investigated internal initiator to improve safety, increase yield, reduce weight 10 lb. |
| Des Moines | 21:00.00.12 13-Jun-62 | NTS, Area 12j | Tunnel | -660 | 2.9 | LRL | WD | Sim. to Platte |
| Daman I | 17:00.00.13 21-Jun-62 | NTS, Area 3be | Shaft | -854 | <20 | LASL | WD | Successful |
| Haymaker | 18:00.00.12 27-Jun-62 | NTS, Area 3aus | Shaft | -1340 | 67 | LASL | WD | Possible Mocassin device (tested in Project 58 #2, HT-II Hidalgo) |
| Marshmallow | 17:00 28-Jun-62 | NTS, Area 16a | Tunnel | -1050 | <20 | DOD/LRL | WE | Simulated high altitude effects shot in low pressure chamber, successful, x-ray effects of re-entry vehicles investigated |
| Sacramento | 21:30.00.16 30-Jun-62 | NTS, Area 9v | Shaft | -500 | <20 | LRL | WD | Sim. to White device, probable XW-58 test |