{"type":"programs","slug":"1957-operation-plumbbob","title":"Operation Plumbbob","url":"https://disclosdex.com/programs/1957-operation-plumbbob","description":"1957 Nevada test series studied nuclear weapon effects, launched the manhole cover, and jolted Area 51.","date":"1957-05-28T00:00:00.000Z","tags":["Nuclear"],"updated":"2025-06-13T13:26:43.000Z","connectionCount":0,"content":{"markdown":"## Origins and Context\n\nOperation Plumbbob was a major sequence of nuclear tests at the Nevada Test Site conducted by the Department of Defense and Atomic Energy Commission. The series evaluated weapon designs and blast effects, with multiple underground and atmospheric shots.[^1]\n\n## Key Moments\n\n- Pascal-B shot on 27 August 1957 welded a steel cap over a shaft, launching it skyward at possible escape velocity.[^2][^3]\n- The 74 kiloton Hood airburst shook nearby Groom Lake,[^4][^5] leading to reports of strange lights around the base during repairs.\n\n## Legacy\n\nPlumbbob advanced knowledge of blast radiation, containment, and effects on military structures. Some tests overlapped with early activity at Area 51, fueling later UFO speculation.\n\n[^1]: [DOE - United States Atmospheric Nuclear Weapons Tests: Operation Plumbbob](https://www.osti.gov/opennet/manhattan-project-history/publications/DOENTSAtmospheric.pdf)\n\n[^2]: [Brownlee, R.R. - Learning to Contain Underground Nuclear Explosions](https://nuclearweaponarchive.org/Usa/Tests/Brownlee.html)\n\n[^3]: [DOE/NNSA - Battlefield of the Cold War: The Nevada Test Site, Volume I](https://www.osti.gov/opennet/servlets/purl/969352.pdf)\n\n[^4]: [Roadrunners Internationale - Groom Lake Timeline: The First Fifty Years](https://roadrunnersinternationale.com/area51_timeline.html)\n\n[^5]: [LLNL - Hood Event, Plumbbob Operation, Nevada Test Site](https://www.llnl.gov/hood-event-plumbbob-operation-nevada-test-site)\n\n[^6]: [Nuclear Weapon Archive - Operation Plumbbob Tests](https://nuclearweaponarchive.org/Usa/Tests/Plumbob.html)","readingTime":"1 min read"},"relatedRecords":[],"citation":{"canonicalUrl":"https://disclosdex.com/programs/1957-operation-plumbbob","title":"Operation Plumbbob","publisher":"Disclosdex","retrievedFrom":"https://disclosdex.com/api/v1/programs/1957-operation-plumbbob","license":"CC-BY-4.0"}}