See also: List of nuclear weapons tests of the United States.
Operation Upshot–Knothole | |
Picture Description: | Upshot-Knothole Grable, 15 kilotons. |
Country: | United States |
Test Site: |
|
Period: | 1953 |
Number Of Tests: | 11 |
Test Type: | free air drop, gun deployed, tower |
Max Yield: | 61ktTNT |
Next Series: | Operation Castle |
Operation Upshot–Knothole was a series of eleven nuclear test shots conducted in 1953 at the Nevada Test Site. It followed Operation Ivy and preceded Operation Castle.
Over 21,000 soldiers took part in the ground exercise Desert Rock V in conjunction with the Grable shot.[1] Grable was a 280mm Artillery Fired Atomic Projectile (AFAP) shell fired from the "Atomic Cannon" and was viewed by a number of high-ranking military officials.
The test series was notable as containing the first time an AFAP shell was fired (GRABLE Shot), the first two shots (both fizzles) by University of California Radiation Laboratory—Livermore (now Lawrence Livermore National Laboratory), and for testing out some of the thermonuclear components that would be used for the massive thermonuclear series of Operation Castle. One primary device (RACER) was tested in thermonuclear system mockup assemblies of TX-14, TX-16, and TX-17/TX-24, to examine and evaluate the behaviour of radiation cases and the compression of the secondary geometries by the primary's x-rays prior to full-scale testing during Castle.[2] Following RACER's dodgy performance, the COBRA primary was used in the emergency capability ALARM CLOCK, JUGHEAD, RUNT I, RUNT II thermonuclear devices, as well as in the SHRIMP device. RACER IV (as redesigned and proof-tested in the Simon test) was employed as primary for the ZOMBIE, RAMROD and MORGENSTERN devices.
Planned yield for Annie was, actual yield based on radiochemical analysis was .[3]
Planned yield for Nancy was, actual yield based on radiochemical analysis was .
Planned yield for Simon was, actual yield based on radiochemical analysis was .
Planned yield for Harry was, actual yield based on radiochemical analysis was .
Planned yield for Encore was, actual yield based on radiochemical analysis was .
- style="vertical-align: top;" !style="background:#ffdead;" | Name[4] !style="background:#efefef;" | Date time (UT) !style="background:#ffdead;" | Local time zone[5] [6] !style="background:#efefef;" | Location[7] !style="background:#ffdead;" | Elevation + height[8] !style="background:#efefef;" | Delivery[9] Purpose[10] !style="background:#efefef;" | Device[11] !style="background:#ffdead;" | Yield[12] !style="background:#efefef;" class="unsortable" | Fallout[13] !style="background:#ffdead;" class="unsortable" | References !style="background:#efefef;" class="unsortable" | Notes | - style="vertical-align: top;" ! Annie | 13:20:00.3 | PST (-8 hrs) | NTS Area 337.0477°N -116.022°W | 1230m (4,040feet) + 90m (300feet) | tower, weapons development | TX-5HE "XR-3" Type D pit | I-131 detected, 2.4MCi | Investigated yield-vs-initiation time curve. Live news coverage. Desert Rock V. Two 2-story houses, 50 autos, bomb shelters in effects test. | - style="vertical-align: top;" ! Nancy | 13:10:00.0 | PST (-8 hrs) | NTS Area 437.0955°N -116.1037°W | 1230m (4,040feet) + 90m (300feet) | tower, weapons development | TX-14 "Nevada Zombie" | I-131 detected, 3.6MCi | Component test of TX-14 containing minimal quantities of Li-6D. Desert Rock V. First proof-test of the RACER boosted primary with disappointing performance. | - style="vertical-align: top;" ! Ruth | 13:00:00.0 | PST (-8 hrs) | NTS Area 737.0827°N -116.0248°W | 1270m (4,170feet) + 90m (300feet) | tower, weapons development | MK-6[14] "Hydride I" | I-131 detected, 28kCi | 1st UCRL device, a uranium deuteride core, meant to explore deuterated polyethylene mixed with uranium as thermonuclear fuel,[15] and if successful to lead also to a compact thermonuclear primary. Predicted yield was 1.5 to 3 kilotons, max. theoretical was 20 kt. Device fizzled - deuterium moderated (slowed-down) neutrons more than expected and quenched the reaction. Embarrassing for designers, as it left 200feet of tower still standing (see image of tower). | - style="vertical-align: top;" ! Dixie | 15:29:38.4 | PST (-8 hrs) | NTS Area 737.0847°N -116.0189°W | 1284m (4,213feet) + 1830m (6,000feet) | free air drop, weapons development | MK-5D"DD-1" | I-131 detected, 1.7MCi | TX-5D proof test, a boosting experiment using lithium deuteride in solid or crystalline form, investigating initiation via deuterium; a cheap method to initiate a chain reaction. Exploded 600feet ENE of intended zero point. | - style="vertical-align: top;" ! Ray | 12:44:59.8 | PST (-8 hrs) | NTS Area 437.0989°N -116.0933°W | 1296m (4,252feet) + 30m (100feet) | tower, weapons development | MK-6"Hydride II" | [16] | I-131 detected, 28kCi | 2nd UCRL device, uranium deuteride meant to explore deuterated polyethylene mixed with uranium as thermonuclear fuel, and if successful to lead also to a compact thermonuclear primary; Used different mix from Ruth and it also fizzled. A 100-foot tower was apparently used to avoid embarrassment in case of fizzle. | - style="vertical-align: top;" ! Badger | 12:35:00.0 | PST (-8 hrs) | NTS Area 237.1383°N -116.1187°W | 1370m (4,500feet) + 90m (300feet) | tower, weapons development | TX-16 "Buzzard" | I-131 detected, 3.6MCi | Component test of the TX-16 using a cryogenic mockup secondary and the TX-16 radiation case. Also tested RACER primary, which performed below expectations again. Desert Rock V. | - style="vertical-align: top;" ! Simon | 12:29:59.8 | PST (-8 hrs) | NTS Area 137.053°N -116.1036°W | 1294m (4,245feet) + 90m (300feet) | tower, weapons development | TX-17/24 "Simultaneity" | I-131 detected, 6.3MCi | Component test of TX-17/24 series using the RACER IV primary, a modified RACER core containing two additional kilograms of HEU in the original design tested in Nancy, a thermonuclear secondary mockup. | - style="vertical-align: top;" ! Encore | 15:29:55.4 | PST (-8 hrs) | NTS Area 536.8°N -115.929°W | 940m (3,080feet) + 740m (2,430feet) | free air drop, weapon effect | I-131 detected, 3.9MCi | "Effects" test. Dropped 950feet SSW of target. Desert Rock V, bad exposures for troops and bad downwinder fallout. | - style="vertical-align: top;" ! Harry | 12:04:59.5 | PST (-8 hrs) | NTS Area 337.0402°N -116.0261°W | 1224m (4,016feet) + 90m (300feet) | tower, weapons development | TX-13D "Hamlet" | I-131 detected, 4.6MCi | New hollow core design, most efficient pure-plutonium device under 100 kt indicates very good compression. Major effects testing of a high elevation explosion. Heaviest downwind contamination measured. | - style="vertical-align: top;" ! Grable | 15:30:00.3 | PST (-8 hrs) | Launch from NTS Areas 5, 11, Frenchman Flat: 536.7043°N -115.9739°W, elv: 950m+5mm (3,120feet+16feetm); Detonation over NTS 36.793°N -115.9156°W | 960m (3,150feet) + 160m (530feet) | gun deployed, weapon effect | W9 AFAP "Gun" | I-131 detected, 2.1MCi | The 2nd of four gun-type device tests. Fired from the M65 Atomic Cannon "Atomic Annie" 11km (07miles) downrange. 280mm shell, 365kg (805lb). Detonation at SW of target. Desert Rock V. Major effects test. | - style="vertical-align: top;" ! Climax | 11:14:56.7 | PST (-8 hrs) | NTS Area 737.0875°N -116.0192°W | 1288m (4,226feet) + 410m (1,350feet) | free air drop, weapons development | MK-7, "Cobra", Type D pit | I-131 detected, 8.6MCi | Proof test of a boosted MK-7 device, intended to be used as a primary in Castle. Initially it was intended only for the TX-15. After RACER's inconsistent behaviour it was opted for all "emergency capability" devices instead.. The bomb detonated 320feet NW of target. Composite implosion system in a Type D pit. Used Cyclotol 75/25 explosive mixture. |