The M143 bomblet was a biological

cluster bomb A cluster munition is a form of air-dropped or ground-launched explosive weapon that releases or ejects smaller submunitions. Commonly, this is a cluster bomb that ejects explosive bomblets that are designed to kill personnel and destroy vehi ...

sub-munition developed by the United States during the 1960s. The spherical bomblet was the biological version of the Sarin-filled M139 chemical bomblet.

History

The M143 bomblet was produced at the peak of U.S. biological delivery systems development during the 1960s. Essentially a biological version of the M139 bomblet, the M143 was smaller than the M139.Smart, Jeffery K.
Medical Aspects of Chemical and Biological Warfare
'': Chapter 2 - History of Chemical and Biological Warfare: An American Perspective,
PDF
p. 51), ''

Borden Institute The Borden Institute is a U.S. Army “Center of Excellence in Military Medical Research and Education”. In 1987, U.S. Army Colonel Russ Zajtchuk conceived the idea for a “Center of Excellence in Military Medical Research and Education,” u ...

'', Textbooks of Military Medicine, PDF via

Maxwell-Gunter Air Force Base Maxwell Air Force Base , officially known as Maxwell-Gunter Air Force Base, is a United States Air Force (USAF) installation under the Air Education and Training Command (AETC). The installation is located in Montgomery, Alabama, United States. ...

, accessed November 12, 2008. The Sergeant missile system used the M143 in its M210

warhead A warhead is the section of a device that contains the explosive agent or toxic (biological, chemical, or nuclear) material that is delivered by a missile, rocket (weapon), rocket, torpedo, or bomb. Classification Types of warheads include: *E ...

, which could hold 720 individual bomblets. If that system released the bomblets at an altitude of , the weapon could attain a coverage area of .

Specifications

The M143 was a spherical bomblet that had a diameter of . Designed to carry a liquid

biological agent Biological agents, also known as biological weapons or bioweapons, are pathogens used as weapons. In addition to these living or replicating pathogens, toxins and Toxin#Biotoxins, biotoxins are also included among the bio-agents. More than 1,2 ...

, the M143 carried a explosive charge meant to disseminate the agent upon impact. Eight percent of the liquid released from the M143 was in the form of an inhalable aerosol. When filled, the bomblet had a mass of and of liquid agent could contain 6 trillion anthrax spores.''Countermeasures''
Chapter 6 - An Overview of Emerging Missile State Countermeasures
p. 14, accessed November 12, 2008. Given the lethality of even a small amount of biological agent, the amount of anthrax contained in the bomblet would be the equivalent of 300 million lethal doses.

Tests involving the M143

The M143 bomblet was used in multiple biological weapons effectiveness tests by the

U.S. Army The United States Army (USA) is the primary land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of the United Stat ...

. Two tests, collectively dubbed "Yellow Leaf" sought to test the M143 and biological agents in a jungle environment. Tests planned for the

Panama Canal Zone The Panama Canal Zone (), also known as just the Canal Zone, was a International zone#Concessions, concession of the United States located in the Isthmus of Panama that existed from 1903 to 1979. It consisted of the Panama Canal and an area gene ...

using tiara as a simulant could not be completed because of "international considerations", and an alternate test site was found in Hawaii at the Ōlaʻa Forest, southwest of

Hilo Hilo () is the largest settlement in and the county seat of Hawaii County, Hawaiʻi, United States, which encompasses the Island of Hawaiʻi, and is a census-designated place (CDP). The population was 44,186 according to the 2020 census. I ...

. The goals of the Yellow Leaf tests were to learn the effectiveness of the M143 in a jungle environment, the area of coverage for a

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Department of Defense. It is the world's most powerful navy with the largest displacement, at 4.5 million tons in 2021. It has the world's largest aircraft ...

MISTEYE I weapons system Sergeant missile biological warhead over a jungle.Fact Sheet - Yellow Leaf
", ''Office of the Assistant Secretary of Defense (Health Affairs)'', Deployment Health Support Directorate, accessed November 12, 2008. The Panama tests took place in February 1964 and the Hawaii tests, using the simulant '' Bacillus globigii'', took place from April-May 1966. Other tests, known as "Red Cloud", took place from November 1966-February 1967 in the

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near

Fort Greely Fort Greely is a United States Army launch site for anti-ballistic missiles located about southeast of Fairbanks, Alaska, Fairbanks, Alaska. It is also the home of the Cold Regions Test Center (CRTC), as Fort Greely is one of the coldest areas ...

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

. The main goal of Red Cloud was to obtain data on ''

Francisella tularensis ''Francisella tularensis'' is a pathogenic species of Gram-negative coccobacillus, an aerobic bacterium. It is nonspore-forming, nonmotile, and the causative agent of tularemia, the pneumonic form of which is often lethal without treatment. It i ...

'' and its decay rate as well as its animal infectivity data. The tests involved M143 bomblets being dropped from a tower-mounted gun into a wintertime spruce forest. E26 and M32 dissemination devices were also used. The tests disseminated the following biological agents or simulants: ''F. tularensis'' (both wet and dry variants), ''B. globigii'', ''

Serratia marcescens ''Serratia marcescens'' () is a species of bacillus (shape), rod-shaped, Gram-negative bacteria in the family Yersiniaceae. It is a facultative anaerobe and an opportunistic pathogen in humans. It was discovered in 1819 by Bartolomeo Bizio in Pa ...

'', and ''

Escherichia coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly fo ...

''. Both Red Cloud and Yellow Leaf were overseen by the U.S. Army's

Deseret Test Center The Deseret Test Center was a U.S. Army operated command in charge for testing chemical and biological weapons during the 1960s. The Deseret was headquartered at Fort Douglas, Utah, a former U.S. Army base. History Progress toward standardizin ...

,Fact Sheet - Red Cloud
", ''Office of the Assistant Secretary of Defense (Health Affairs)'', Deployment Health Support Directorate, accessed November 12, 2008. and were part of

Project 112 Project 112 was a biological and chemical weapon experimentation project conducted by the United States Department of Defense from 1962 to 1973. The project started under John F. Kennedy's administration, and was authorized by his Secretary of ...

.Project 112/SHAD Fact Sheets
", Force Health Protection & Readiness Policy & Programs, The Chemical-Biological Warfare Exposures Site, accessed November 13, 2008.

References

{{U.S. biological weapons Biological weapon delivery systems Submunitions Military equipment introduced in the 1960s

History

Specifications

Tests involving the M143

See also

References