ImportMaster at 17:16, 13 February 2022

2022-02-13T17:16:58Z

New page

{{Short description|Type of weapon}}
{{Redirect|Smart bomb}}
[[File:BOLT117LGB.jpg|thumb|300px|[[BOLT-117]], the world's first [[laser-guided bomb]] ]]

A '''guided bomb''' (also known as a '''smart bomb''', '''guided bomb unit''', or '''GBU''') is a [[precision-guided munition]] designed to achieve a smaller [[circular error probable]] (CEP).<ref>{{cite web|url=http://www.fas.org/man/dod-101/sys/smart/docs/paper53.htm|title=Precision guided munitions and the new era of warefare|last=Hamilton|first=Richard|year=1995|publisher=Air Power Studies Centre, Royal Australian Air Force|access-date=2009-02-02}}</ref><ref>"''[http://www.britishpathe.com/video/selected-originals-bomb-with-a-brain Bomb With A Brain]''". [[British Pathé]] newsreel 52/51A, June 23, 1952. Accessed 2013-04-04.</ref>

The creation of precision-guided munitions resulted in the retroactive renaming of older bombs as [[unguided bombs]] or "dumb bombs".

== Payload ==
A guided bomb of a given weight must carry fewer explosives to accommodate the guidance mechanisms.

== Guidance ==
{{Main|Missile guidance}}
[[Image:Image-GBU-24 Missile testmontage-gi BLU-109 bomb.jpg|thumb|right|A laser-guided [[GBU-24]] ([[BLU-109]] warhead variant) strikes its target.]]

Guided bombs carry a guidance system which is usually monitored and controlled from an external device.

=== Radio ===
{{Main|command guidance}}
The Germans were first to introduce Precision Guided Munitions (PGMs) in combat, using the 1,400-kg (3,100 lb) [[MCLOS]]-guidance [[Fritz X]] to successfully attack the Italian [[battleship]] [[Italian battleship Roma (1940)|''Roma'']] in September 1943. The closest [[Allies of World War II|Allied]] equivalents were the 1,000-lb (454 kg) [[AZON]] (AZimuth ONly), used in both Europe and the [[China Burma India Theater|CBI Theater]], and the [[United States Navy|US Navy]]'s [[Bat (guided bomb)|Bat]], primarily used in the Pacific Theater of World War II which used autonomous, on-board radar guidance. In addition, the U.S. tested the rocket-propelled [[LBD-1 Gargoyle|Gargoyle]]; it never entered service.<ref>Fitzsimons, ''op. cit.'', Volume 10, p.1090, "Gargoyle".</ref> No Japanese remotely guided PGMs ever saw service in World War II.

The [[United States Army Air Forces]] used similar techniques with [[Operation Aphrodite]], but had few successes; the German [[Mistel]] (Mistletoe) "[[parasite aircraft]]" was no more effective.

The U.S. programs restarted in the [[Korean War]]. In the 1960s, the ''[[electro-optical]] bomb'' (or ''camera bomb'') was reintroduced. They were equipped with [[television]] [[camera]]s and flare sights, by which the bomb would be steered until the flare superimposed the target. The camera bombs transmitted a "bomb's eye view" of the target back to a controlling aircraft. An operator in this aircraft then transmitted control signals to steerable fins fitted to the bomb. Such weapons were used increasingly by the [[USAF]] in the last few years of the [[Vietnam War]] because the political climate was increasingly intolerant of civilian casualties, and because it was possible to strike difficult targets (such as bridges) effectively with a single mission; the [[Thanh Hoa Bridge]], for instance, was attacked repeatedly with gravity bombs, to no effect, only to be dropped in one mission with PGMs.

Although not as popular as the newer [[JDAM]] and [[JSOW]] weapons, or even the older [[laser-guided bomb]] systems, weapons like the [[AGM-62 Walleye]] TV-guided bomb are still being used, in conjunction with the [[AAW-144]] Data Link Pod, on [[US Navy]] [[F/A-18 Hornet]]s.

=== Infrared ===
{{Main|Infrared homing}}
In World War II, the U.S. [[National Defense Research Committee]] developed the [[VB-6 Felix]], which used infrared to home on ships. While it entered production in 1945, it was never employed operationally.<ref>Fitzsimons, ''op. cit.'', Volume 9, p.926, "Felix".</ref>

=== Laser ===
{{Main|Laser guidance}}

[[File:GBU-10 shortly before it impacts a small boat during a training exercise.jpg|thumb|GBU-10 shortly before it impacts a small boat during a training exercise]]
In 1962, the US Army began research into [[laser]] guidance systems and by 1967 the USAF had conducted a competitive evaluation leading to full development of the world's first [[laser-guided bomb]], the [[BOLT-117]], in 1968. All such bombs work in much the same way, relying on the target being illuminated, or "painted," by a laser target designator on the ground or on an aircraft. They have the significant disadvantage of not being usable in poor weather where the target illumination cannot be seen, or where it is not possible to get a target designator near the target. The laser designator sends its beam in a series of [[encryption|encrypted]] pulses so the bomb cannot be confused by an ordinary laser, and also so multiple designators can operate in reasonable proximity.

Laser-guided weapons did not become commonplace until the advent of the microchip. They made their practical debut in Vietnam, where on 13 May 1972 when they were used in the second successful attack on the Thanh Hoa Bridge ("Dragon's Jaw"). This structure had previously been the target of 800 American sorties<ref>[http://www.mn.afrl.af.mil/public/vietnam.html Thanh Hoa Bridge] {{webarchive|url=https://web.archive.org/web/20051109035612/http://www.mn.afrl.af.mil/public/vietnam.html |date=2005-11-09 }}</ref> (using unguided weapons) and was partially destroyed in each of two successful attacks, the other being on 27 April 1972 using [[AGM-62 Walleye|Walleye]]s. That first mission also had laser-guided weapons, but bad weather prevented their use. They were used, though not on a large scale, by the British forces during the 1982 [[Falklands War]].<ref>[http://www.britains-smallwars.com/Falklands/air-war.htm Britain's Small Wars] {{webarchive|url=https://web.archive.org/web/20110120025712/http://www.britains-smallwars.com/Falklands/air-war.htm |date=2011-01-20 }}</ref> The first large-scale use of smart weapons came in 1991 during Operation [[Desert Storm]] when they were used by coalition forces against [[Iraq]]. Even so, most of the air-dropped ordnance used in that war was "dumb," although the percentages are biased by the large use of various (unguided) [[cluster bomb]]s. Laser-guided weapons were used in large numbers during the 1999 [[Kosovo War]], but their effectiveness was often reduced by the poor weather conditions prevalent in the southern Balkans.

There are two basic families of laser-guided bombs in American (and American-sphere) service: the [[Paveway]] II and the Paveway III. The Paveway III guidance system is more aerodynamically efficient and so has a longer range, however it is more expensive. Paveway II 500-pound LGBs (such as GBU-12) are a cheaper lightweight PGM suitable for use against vehicles and other small targets, while a Paveway III 2000-pound penetrator (such as GBU-24) is a more expensive weapon suitable for use against high-value targets. GBU-12s were used to great effect in the first [[Gulf War]], dropped from [[General Dynamics F-111|F-111F]] aircraft to destroy Iraqi armored vehicles in a process referred to as "tank plinking."

=== Satellite ===

[[File:F-22 bomb.jpg|thumb|An [[F-22]] releases a [[Joint Direct Attack Munition|JDAM]] from its center internal bay while flying at supersonic speed]]

Lessons learned during the first Gulf War showed the value of precision munitions, yet they also highlighted the difficulties in employing them—specifically when visibility of the ground or target from the air was degraded.<ref>[http://www.af.mil/news/story.asp?storyID=123017613 JDAM continues to be warfighter's weapon of choice]</ref> The problem of poor visibility does not affect satellite-guided weapons such as [[Joint Direct Attack Munition]] (JDAM) and [[Joint Stand-Off Weapon]] (JSOW), which make use of the United States' [[Global Positioning System|GPS]] system for guidance. This weapon can be employed in all weather conditions, without any need for ground support. Because it is possible to [[Radar jamming and deception|jam]] GPS, the guidance package reverts to [[inertial navigation]] in the event of GPS signal loss. Inertial navigation is significantly less accurate; the JDAM achieves a published circular error probable (CEP) of 13 m under GPS guidance, but typically only 30 m under inertial guidance (with free fall times of 100 seconds or less).<ref>U.S. Air Force [https://web.archive.org/web/20030624083412/http://www.af.mil/factsheets/factsheet.asp?fsID=108 Factsheets: Joint Direct Attack Munition]</ref><ref>[http://www.globalsecurity.org/military/systems/munitions/jdam-specs.htm JDAM Specifications]</ref>

[[File:BGT Hosbo.jpg|thumb|left|[[HOPE/HOSBO]] of the [[German Air Force|Luftwaffe]] with a combination of GPS/INS and electro-optical guidance]]

The precision of these weapons is dependent both on the precision of the measurement system used for location determination and the precision in setting the coordinates of the target. The latter critically depends on intelligence information, not all of which is accurate. According to a CIA report, the accidental [[NATO bombing of the People's Republic of China embassy in Belgrade|bombing of the Chinese embassy in Belgrade]] during [[Operation Allied Force]] by NATO aircraft was attributed to faulty target information.<ref>[https://www.cia.gov/cia/public_affairs/speeches/1999/dci_speech_072299.html DCI Statement on the Belgrade Chinese Embassy] {{webarchive|url=https://web.archive.org/web/20061004025533/https://www.cia.gov/cia/public_affairs/speeches/1999/dci_speech_072299.html |date=2006-10-04 }}</ref> However, if the targeting information ''is'' accurate, satellite-guided weapons are significantly more likely to achieve a successful strike in any given weather conditions than any other type of precision-guided munition.
Other military satellite guidance systems include: Russian [[GLONASS]], European [[Galileo (satellite navigation)]], Chinese [[BeiDou Navigation Satellite System]], regional [[Indian Regional Navigation Satellite System]], Japanese regional [[Quasi-Zenith Satellite System]].

== History ==

The guided bomb had its origins in [[World War II]]. Its usage increased after the success of the weapon in the Gulf War.

=== World War II ===
[[Image:BAT-PB4Y-wingbat.jpg|thumb|A [[Bat (guided bomb)|BAT guided bomb]]]]
In World War II, the aforementioned Fritz X and [[Henschel Hs 293]] guided ordnance designs were used in combat by Nazi Germany against ships, as the [[USAAF]] would do with the Azon in hitting bridges and other hard-to-hit targets in both Western Europe and Burma. Later, U.S. [[National Defense Research Committee]] developed the [[VB-6 Felix]], which used infrared to home on ships. While it entered production in 1945, it was never employed operationally.<ref>Fitzsimons, ''op. cit.'', Volume 9, p.926, "Felix".</ref>

=== Korean War ===

The US briefly deployed the [[ASM-A-1 Tarzon]] (or VB-13 Tarson) bomb (a [[Tallboy (bomb)|Tallboy]] fitted with radio guidance) during the [[Korean War]], dropping them from [[Boeing B-29 Superfortress]]es.

=== Vietnam War ===

In 1962, the US Army began research into [[laser]] guidance systems and by 1967 the USAF had conducted a competitive evaluation leading to full development of the world's first [[laser-guided bomb]], the [[BOLT-117]], in 1968.

===Gulf War ===

[[GBU-12 Paveway II]]s were used to great effect in the first [[Gulf War]], dropped from [[General Dynamics F-111|F-111F]] aircraft to destroy Iraqi armored vehicles in a process referred to as "[[tank plinking]]".

=== Era of non-linear warfare ===

Lessons learned during the first Gulf War showed the value of guided bombs.

=== Advanced guidance concepts ===
Responding to after-action reports from pilots who employed laser and/or satellite guided weapons, [[Boeing]] has developed a Laser JDAM (LJDAM) to provide both types of guidance in a single kit. Based on the existing [[Joint Direct Attack Munition|JDAM]] configurations, a laser guidance package is added to a GPS/INS guided weapon to increase the overall accuracy of the weapons.<ref>[http://www.boeing.com/defense-space/missiles/jdam/docs/laser_jdam_overview.pdf Boeing Laser JDAM]</ref> Raytheon has developed the Enhanced Paveway family, which adds GPS/INS guidance to their Paveway family of laser-guidance packages.<ref>[http://www.raytheon.com/products/stellent/groups/public/documents/content/cms01_055758.pdf Raytheon Enhanced Paveway] {{webarchive|url=https://web.archive.org/web/20080307042008/http://www.raytheon.com/products/stellent/groups/public/documents/content/cms01_055758.pdf |date=2008-03-07 }}</ref> These "hybrid" laser and GPS guided weapons permit the carriage of fewer weapons types, while retaining mission flexibility, because these weapons can be employed equally against moving and fixed targets, or targets of opportunity. For instance, a typical weapons load on an F-16 flying in the [[Iraq War]] included a single 2,000-lb JDAM and two 1,000-lb LGBs. With LJDAM, and the new [[Small Diameter Bomb]], these same aircraft can carry more bombs if necessary, and have the option of satellite or laser guidance for each weapon release.

==See also==
* [[XM1156 Precision Guidance Kit]]
* [[M982 Excalibur]]
* [[XM395 Precision Guided Mortar Munition]]
* [[M712 Copperhead]]
* [[Krasnopol (weapon)]]
* [[Strix mortar round]]
* [[Cruise missile]]
* [[Wire-guided missile]]
* [[Glide bomb]]
* [[Precision-guided munition]]
* [[Guidance system]]
* [[Missile]]
* [[Missile guidance]]
* [[Terminal guidance]]
* [[Proximity sensor]]
* [[Artillery fuze]]
* [[Magnetic proximity fuze]]
* [[Proximity fuze]]

==Notes==
{{Reflist}}

==External links==
*"''[http://www.britishpathe.com/video/selected-originals-bomb-with-a-brain Bomb With A Brain]''". [[British Pathé]] newsreel 52/51A, June 23, 1952.
*[http://science.howstuffworks.com/smart-bomb.htm How Smart Bombs Work]
*[http://www.tfcbooks.com/articles/tws10.htm A Brief History of Precision Guided Weapons]
*[http://news.bbc.co.uk/1/hi/world/middle_east/1184086.stm "Smart bombs" missed Iraqi targets] BBC story on the first employment of the JSOW, guidance failures were attributed to a software error that was subsequently fixed.
*[http://news.bbc.co.uk/2/hi/americas/2805775.stm "Fact File: Smart Bombs - not so Smart] BBC story discussing the limitations of guided munition employment.
*[http://www.janes.com/defence/air_forces/news/misc/misc060817_1_n.shtml Ukraine develops indigenous guided airborne weapons] Article about Ukrainian guided bomb development, August 2006
*[http://www.vectorsite.net/twbomb_03.html "World War II Glide Bombs] World War II Glide Bombs (Part1)
*[http://www.vectorsite.net/twbomb_04.html "World War II Glide Bombs] World War II Glide Bombs (Part2)
*[http://www.vectorsite.net/twbomb_05.html "World War II Glide Bombs] Modern Glide Bombs

{{Authority control}}

[[Category:Weapon guidance]]
[[Category:Aerial bombs]]
[[Category:Targeting (warfare)]]

Guided bomb - Revision history

ImportMaster at 17:16, 13 February 2022