Permissive Action Link

Permissive Action Link

A Permissive Action Link (PAL) is a security device for nuclear weapons. Its purpose is to prevent unauthorized arming or detonation of the weapon.

The United States Department of Defense definition is:

The earliest PALs were little more than locks introduced into the control systems of a nuclear weapon, that would inhibit either the detonation, or the removal of safety features of the weapon. More recent innovations have included encrypted firing parameters, which must be decrypted to properly detonate the warhead, plus anti-tamper systems which intentionally mis-detonate the weapon, destroying it without giving rise to a useful nuclear explosion.

These combination locks were installed on Minuteman ICBMs in the 1960s. However, the Strategic Air Command in Omaha worried that in case of need the codes would not be available, so they quietly decided to set them to 00000000; checking this combination was even present on the launch checklists. This was not changed until 1977. [ [http://www.cdi.org/blair/permissive-action-links.cfm Keeping Presidents in the Nuclear Dark (Episode #1: The Case of the Missing "Permissive Action Links") - Bruce G. Blair, Ph.D ] ] In 2007 the British Government revealed that its Nuclear Weapons were not equipped with Permissive Action Links. [ [http://news.bbc.co.uk/2/hi/programmes/newsnight/7097101.stm BBC NEWS Programmes | Newsnight | British nukes were protected by bike locks ] ]

PAL devices were also installed on Sergeant, Pershing, and WAC Corporal missiles as well as the Nike-Hercules, Honest John rockets, the Davy Crockett system, and 155 mm Howitzer, 8 inch howitzer rounds.

The PAL or PAL-like devices have been portrayed in various settings by the entertainment industry, such as in the computer game Metal Gear Solid, the motion picture WarGames, and the television series 24 season 4.

References

ee also

* Emergency Action Message
*Positive Enable System

External links

* http://nuclearweaponarchive.org/Usa/Weapons/Pal.html
* http://www.cs.columbia.edu/~smb/nsam-160/pal.html
* [http://www.brook.edu/fp/projects/nucwcost/box9_2.htm The JCAE and the Development of the Permissive Action Link]
* [http://www.cdi.org/blair/permissive-action-links.cfm Keeping Presidents in the Nuclear Dark]
* [http://www.cl.cam.ac.uk/~rja14/book.html Security Engineering] , [http://www.cl.cam.ac.uk/~rja14/Papers/SE-11.pdf Chapter 11: Nuclear Command and Control] , Ross Anderson, ISBN 0-471-38922-6
*http://news.bbc.co.uk/media/avdb/news/uk/video/133000/bb/133417_16x9_bb.asx
* [http://www.bbc.co.uk/mediaselector/check/player/nol/newsid_7090000/newsid_7099100?redirect=7099125.stm&news=1&nbram=1&nbwm=1&bbram=1&bbwm=1 "The Dr. Strangelove scenario" - a BBC "Newsnight" report featuring the lack of security features on the WE.177] (streaming video)


Wikimedia Foundation. 2010.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • Permissive Action Link — Eine externe PAL Kontrolleinheit. Sie kostete ursprünglich 290.000 US Dollar, bevor die Stückkosten schließlich signifikant reduziert werden konnten[1] Permissive Action Link (PAL) ist die Bezeichnung einer US amerikanischen… …   Deutsch Wikipedia

  • permissive action link — A device included in or attached to a nuclear weapon system to preclude arming and/or launching until the insertion of a prescribed discrete code or combination. It may include equipment and cabling external to the weapon or weapon system to… …   Military dictionary

  • Prescribed Action Link — Eine externe PAL Kontrolleinheit. Sie kostete ursprünglich 290.000 US Dollar, bevor die Stückkosten schließlich signifikant reduziert werden konnten[1] Permissive Action Link (PAL) ist die Bezeichnung einer US amerikanischen… …   Deutsch Wikipedia

  • Proscribed Action Link — Eine externe PAL Kontrolleinheit. Sie kostete ursprünglich 290.000 US Dollar, bevor die Stückkosten schließlich signifikant reduziert werden konnten[1] Permissive Action Link (PAL) ist die Bezeichnung einer US amerikanischen… …   Deutsch Wikipedia

  • 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. [… …   Wikipedia

  • Emergency Action Message — An Emergency Action Message (EAM) is a preformatted message that directs nuclear capable forces to execute specific Major Attack Options (MAOs) or Limited Attack Options (LAOs) in a nuclear war. Individual countries or specific regions may be… …   Wikipedia

  • PAL — permissive action link; personnel allowance list; program assembler language …   Military dictionary

  • Reliable Replacement Warhead — The Reliable Replacement Warhead (RRW) is a controversial new American nuclear warhead design and bomb family that is intended to be simple, reliable and to provide a long lasting, low maintenance future nuclear force for the United States. It is …   Wikipedia

  • Atombombe (Technik) — Kernwaffen, auch als Atomwaffen oder Nuklearwaffen bezeichnet, sind Bomben oder Artilleriegeschosse, die die Energie für eine Explosion aus Kernreaktionen (Kernspaltungen oder verschmelzungen) beziehen (siehe auch Kernwaffenexplosion). Die… …   Deutsch Wikipedia

  • Atombombentechnik — Kernwaffen, auch als Atomwaffen oder Nuklearwaffen bezeichnet, sind Bomben oder Artilleriegeschosse, die die Energie für eine Explosion aus Kernreaktionen (Kernspaltungen oder verschmelzungen) beziehen (siehe auch Kernwaffenexplosion). Die… …   Deutsch Wikipedia

Share the article and excerpts

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