- Operation Hardtack I
-
Operation Hardtack I 
Hardtack OakInformation Country 
United StatesTest site Pacific Proving Grounds Period April - October 1958 Number of tests 35 Max. yield 9.3 Mt Navigation Previous test Project 58A Next test Operation Argus Operation Hardtack I was a series of 35 nuclear tests conducted by the United States in 1958 in the Pacific Ocean.
Contents
Test Blasts
Hardtack I Test Blasts Test Name Date Location Yield Note Image Yucca 28 April, 1958 Enewetak Atoll 1.7 kilotons 85nm NE of Enewetak, high-altitude balloon test at 86,000 feet for ABM development Cactus 5 May, 1958 Enewetak 18 kilotons Test of Mark-43 Primary 11°33′09″N 162°20′50″E / 11.5525°N 162.34722°E, crater has been filled with contaminated soil and debris and covered with concrete cap called "Cactus Dome".[1] 
Fir 11 May, 1958 Bikini Atoll 1.36 megatons 93.4 % fusion yield Butternut 11 May, 1958 Enewetak 81 kilotons TX-46 test, primary only Koa 12 May, 1958 Enewetak 1.37 megatons XW-35 ICBM warhead test Wahoo 16 May, 1958 Enewetak 9 kilotons Deep underwater test (3200 ft.) Holly 20 May, 1958 Enewetak 5.9 kilotons Nutmeg 21 May, 1958 Bikini Atoll 25.1 kilotons Yellowwood 26 May, 1958 Enewetak 330 kilotons Fizzled, TX-46 test, 2.5 megaton yield predicted Magnolia 26 May, 1958 Enewetak 57 kilotons Tobacco 30 May, 1958 Enewetak 11.6 kilotons 2nd stage failed to ignite Sycamore 31 May, 1958 Bikini Atoll 92 kilotons Fizzle, 5 megaton yield predicted Rose 2 June, 1958 Enewetak 15 kilotons Fizzle, 125 kiloton yield predicted Umbrella 8 June, 1958 Enewetak 8 kilotons Shallow depth underwater shot (150 ft.) 
Maple 10 June, 1958 Bikini Atoll 213 kilotons 89 % fission yield predicted Aspen 14 June, 1958 Bikini Atoll 319 kilotons Fired in Castle Bravo crater Walnut 14 June, 1958 Enewetak 1.45 megatons Linden 18 June, 1958 Enewetak 11 kilotons Redwood 27 June, 1958 Bikini Atoll 412 kilotons Elder 27 June, 1958 Enewetak 880 kilotons Oak 28 June, 1958 Enewetak 8.9 megatons TX-46 redesigned full-yield test, successful. 
Hickory 30 June, 1958 Bikini Atoll 14 kilotons Sequoia 1 July, 1958 Enewetak 5.2 kilotons Cedar 2 July, 1958 Bikini Atoll 220 kilotons Dogwood 5 July, 1958 Enewetak 397 kilotons Poplar 12 July, 1958 Bikini Atoll 9.3 megatons Highest test of the Dominic Series, 5th largest U.S. test overall 
Scaevola 14 July, 1958 Enewetak zero Zero yield safety test Pisonia 17 July, 1958 Enewetak 255 kilotons Juniper 22 July, 1958 Bikini Atoll 65 kilotons Final test at Bikini Atoll Olive 22 July, 1958 Enewetak 202 kilotons Pine 26 July, 1958 Enewetak 2 megatons "Clean" version of the three stage Mark-41 design, yield well below the 4-6 megaton prediction Teak 1 Aug., 1958 Johnston Atoll 3.8 megatons ABM effects test, launched by the Redstone ballistic missile, with a 252,000 foot burst height. Miscalculation resulted in detonation directly above launch site. 
Quince 6 Aug., 1958 Enewetak zero Fizzle Orange 12 Aug., 1958 Johnston Atoll 3.8 megatons ABM effects test, launched on the Redstone ballistic missile, 141,000 foot burst height 
Fig 18 Aug., 1958 Enewetak 0.02 kilotons Final test at Enewetak See also
Notes
References
- Chuck Hansen, U. S. Nuclear Weapons: The Secret History (Arlington: AeroFax, 1988) ISBN 0517567407
- The Nuclear Weapons Archive
- "United States Nuclear Tests, July 1945 through September 1992 (DOE/NV-209)" (pdf). U.S. Department of Energy Nevada Operations Office. 2000. http://www.nv.doe.gov/library/publications/historical/DOENV_209_REV15.pdf.
External links
- Operation HARDTACK Military Effects Studies Part I: Basic Effects Structures and Materiel (1958), Department of Defense documentary film, Lookout Mountain Laboratory USAF.
- Operation HARDTACK Military Effects Studies Part II: Underwater Tests (1958), Department of Defense documentary film, Lookout Mountain Laboratory USAF.
- Operation HARDTACK Military Effects Studies Part III: High Altitude Tests (1958), Department of Defense documentary film, Lookout Mountain Laboratory USAF.
Categories:- American nuclear explosive tests
- 1958 in military history
- Enewetak Atoll
Wikimedia Foundation. 2010.
