Strong link weak link


Strong link weak link

A Strong link / weak link and Exclusion zone nuclear detonation mechanism is a type of safety mechanism employed in the arming and firing mechanisms of modern nuclear weapons. It is a form of automatic safety interlock. [ [http://www.cs.columbia.edu/~smb/nsam-160/pal.html Permissive Action Links] by Steven M. Bellovin, accessed March 11, 2007]

The safety mechanism starts by enclosing the electronics and mechanical components used to arm and fire the nuclear weapon with a mechanical and electrical isolation barrier, forming the "Exclusion zone". This is insulated from mechanical, thermal, and electrical disruptions (such as static electricity, lightning, fire). [ [http://nuclearweaponarchive.org/Usa/Weapons/Pal.html Permissive Action Links] , Carey Sublette, at the Nuclear Weapon Archive, accessed March 11, 2007]

Between the exclusion zone and the actual detonators, a normally disconnected link mechanism is used, such as a switch which has a built in motor to activate it. The arming system has to activate the switch in order to connect the firing circuits to the detonators in the weapon. This disconnection, which requires the arming mechanism to operate, is called the "strong link"

It is possible for an accident (rocket explosion, airplane crash, accident while weapon is being moved) to disrupt the weapon and break the integrity of the exclusion zone. As a safety mechanism, a "weak link" is also built into the system. This is a set of components designed to fail at lower stresses (thermal, mechanical, and electrical) than will cause failure of the strong link mechanisms. The weak link acts to break the connection to the detonators before the strong link could be disrupted and fail by the stress of an accident.

These mechanisms do not prevent misuse of the weapon, which is restricted by Permissive Action Link code systems, or an accident from physically causing initiation of the explosives or detonators directly from extremely high temperatures, impact forces, or electrical disturbance such as lightning. The risk of accidental direct detonation is significantly reduced by using insensitive high explosives such as TATB, which is extremely unlikely to detonate due to fire or impact or electricity (see Insensitive munitions). While TATB may decompose or burn in a fire, it is extremely unlikely to detonate as a result of that decomposition or burning.

References

ee also

* Nuclear weapon design
* Permissive Action Link


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • weak — [ wik ] adjective *** ▸ 1 lacking energy ▸ 2 lacking power ▸ 3 easily persuaded ▸ 4 bad in quality ▸ 5 likely to break/fail ▸ 6 with a lot of water ▸ 7 lacking strength ▸ 8 in linguistics 1. ) part of your body that is weak is not as strong or… …   Usage of the words and phrases in modern English

  • strong — [[t]strɒ̱ŋgɪst, AM strɔ͟ːŋgɪst[/t]] ♦ strongest 1) ADJ GRADED Someone who is strong is healthy with good muscles and can move or carry heavy things, or do hard physical work. I m not strong enough to carry him... I feared I wouldn t be able to… …   English dictionary

  • Strong AI — For John Searle s Strong AI hypothesis, see Philosophy of artificial intelligence Strong AI is artificial intelligence that matches or exceeds human intelligence the intelligence of a machine that can successfully perform any intellectual task… …   Wikipedia

  • link — I n. 1) to constitute a link 2) a close; strong; weak link 3) a connecting link 4) the missing link 5) a cuff link 6) a link between; to, with (he has links to the underworld) 7) (misc.) (GB) the fixed link (under the Channel) II v. (D; tr.) to… …   Combinatory dictionary

  • weak */*/*/ — UK [wiːk] / US [wɪk] adjective Word forms weak : adjective weak comparative weaker superlative weakest 1) a) a person who is weak does not have much physical strength or energy The illness had left him too weak to speak. b) part of your body that …   English dictionary

  • link — {{Roman}}I.{{/Roman}} noun 1 connection ADJECTIVE ▪ close, tight ▪ inextricable, strong ▪ tenuous, weak ▪ clear …   Collocations dictionary

  • weak — W2S3 [wi:k] adj ▬▬▬▬▬▬▬ 1¦(physical)¦ 2¦(likely to break)¦ 3¦(character)¦ 4¦(without power)¦ 5¦(without interest)¦ 6¦(without energy)¦ 7¦(not good at doing something)¦ 8¦(money)¦ 9¦(argument/idea)¦ 10¦(drink)¦ …   Dictionary of contemporary English

  • Weak AI — is used to refer to: An artificial intelligence system which is not intended to match or exceed the capabilities of human beings, as opposed to strong AI, which is. Also known as applied AI or narrow AI. (See strong AI) The weak AI hypothesis:… …   Wikipedia

  • link — link1 [liŋk] n. [ME linke < Scand, as in ON hlekkr, Dan lænke, Swed länk, in same senses, akin to OE hlence, link of a chain, coat of mail < base of hlencan, to twist < IE base * kleng , to bend, wind > LANK] 1. any of the series of… …   English World dictionary

  • weak — 01. He was sick, and felt too [weak] to even get out of bed. 02. The goaltender was having a bad day, and let in a couple of [weak] goals. 03. I have a [weakness] for chocolate. I eat the stuff almost every day. 04. She has really [weak] arms so… …   Grammatical examples in English


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.