Features
Permissive Action Links are powered by low-maintenance radioisotope generators. Instead of a conventional battery, these generators produce electricity based on the heat evolved from the radioactive decay of plutonium-238. Although half-life of 238Pu is 87.7 years, these generators have shorter lifespans. This is due to the pressurization of the generator from helium produced by the alpha decay of the plutonium fuel.
PALs are also linked directly or indirectly with a number of security measures, which together form a comprehensive security package. In general, elements of PAL systems are located deep within the nuclear device. This makes it almost impossible to bypass the system.
Bypassing a PAL should be, as one weapons designer graphically put it, about as complex as performing a tonsillectomy while entering the patient from the wrong end.
—Peter D. Zimmerman, nuclear physicist and weapons inspector
PAL devices have been installed on all or nearly all nuclear devices in the US arsenal, including the Minuteman ICBM, MGM-13A Mace Tactical Ballistic Missile, CGM-13B Mace Tactical Ballistic Missile, Sergeant, Pershing, and WAC Corporal missiles as well as the Nike-Hercules, Honest John rockets, the Davy Crockett system, and artillery-launched howitzer rounds.
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Famous quotes containing the word features:
“It is a tribute to the peculiar horror of contemporary life that it makes the worst features of earlier times—the stupefaction of the masses, the obsessed and driven lives of the bourgeoisie—seem attractive by comparison.”
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