W47
The W47 was an American
The W47 was 18 in (460 mm) in diameter and 47 in (1,200 mm) long, and weighed 720 lb (330 kg) in the Y1 model and 733 lb (332 kg) in the Y2 model. The Y1 model had design yield of 600
Design
Declassified British documents indicate that the W47 contained 2.5 kilograms (5.5 lb) of plutonium, 60 kilograms (130 lb) of uranium, 36 kilograms (79 lb) of lithium deuteride and 4 grams (0.14 oz) of tritium.[4]
Live fire testing
The W47 is the only US
Reliability controversy
The W47 warhead had a series of serious reliability problems with the
A number of the Polaris warheads were replaced in the early 1960s, when corrosion of the pits was discovered during routine maintenance.
Failures of the W45, W47, and W52 warheads are still an active part of the debate about the reliability of the US nuclear weapons force moving into the future, without ongoing nuclear testing.[7]
A one-point safety test performed on the W47 warhead just prior the 1958 moratorium (Hardtack/Neptune) failed, yielding a 100-ton explosion. Because the test ban prohibited the testing needed for inherently safe one-point safe designs, a makeshift solution was adopted: a boron-cadmium wire was folded inside the pit during manufacture, and pulled out by a small motor during the warhead arming process. Unfortunately, this wire had a tendency to become brittle during storage, and break or get stuck during arming, which prevented complete removal and rendered the warhead a dud. It was estimated that 50-75% of warheads would fail. This required a complete rebuild of the W47 primaries.[8] The oil used for lubricating the wire also promoted corrosion of the pit.[9]
See also
References
- ^ "LLNL Overviews By Decade - The Fifties" (PDF). National Nuclear Security Administration. Archived from the original (PDF) on 2008-10-15.
Work continued at the Livermore and Sandia laboratories, and through the efforts of weapons designers and engineers, computer specialists, and other experts, the W47 Polaris warhead was created.
- ^ "List of all US Nuclear Bombs". Nuclear Weapons Archive.
- ^ John Pike. "W47". globalsecurity.org. Archived from the original on 2014-11-29. Retrieved 2014-12-14.
- ^ UK Atomic Energy Authority (1964). Weapons Department Atomic Warheads Production Committee, Papers & Minutes (Report). p. 63. TNA AB 16/4675. Archived from the original on 2021-05-23. Retrieved 2022-04-27.
{{cite report}}: CS1 maint: uses authors parameter (link) - ^ Perriman, Wesley (May 6, 2021). "Frigate Bird: The Polaris Missile test at Operation Dominic, Christmas Island". Retrieved September 8, 2023.
- ^ See Donald A. MacKenzie, Inventing accuracy: a historical sociology of nuclear missile guidance (Cambridge, Massachusetts: MIT Press, 1990).
- ^ See for example Nuclear Weapons: The Reliable Replacement Warhead program Archived December 4, 2016, at the Wayback Machine, Jonathan Medalia, 2005, Congressional Research Service.
- (PDF) from the original on 2012-10-16. Retrieved 2014-12-14.
- ^ https://books.google.com/books?id=95eoQSNDp6gC&pg=PA214&dq=warhead+corrosion&lr=&num=50&as_brr=3&ei=C65gS9CtDYLmzAS4i_CLCQ&cd=2#v=onepage&q=&f=false[dead link]
