The E77 balloon bomb was a U.S. anti-crop biological munition based on the design of Japanese

fire balloon An incendiary balloon (or balloon bomb) is a balloon inflated with a lighter-than-air gas such as hot air, hydrogen, or helium, that has a bomb, incendiary device, or Molotov cocktail attached. The balloon is carried by the prevailing winds t ...

s. The E77 used feathers as a vector to disseminate anti-crop agents from a hydrogen-filled balloon and was first developed in 1950.

Background

In the late stages of

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

, Japan employed thousands of incendiary and antipersonnel weapons via unmanned balloon, using some 9,300 of these devices, releasing them into the high altitude jet stream to travel over the Pacific Ocean to the North American mainland. The Japanese use of these balloon munitions inspired the E77, though no direct connection was made between the two.Whitby, Simon M. ''Biological Warfare Against Crops'',
Google Books
, Macmillan, 2002, pp. 157–67, ().

History

Development of the E77 balloon bomb began in 1950. The design of the E77 was based on the design for the World War II Japanese bomb and approved by the Army's Chemical Corps Technical Committee in April 1951. At time of its development the E77 represented one-sixth of all U.S. biological munitions efforts. The E77 was designated a "strategic weapon" and readied for deployment but was never used in warfare as subsequent developments in munitions supplanted the E77, especially the 750-pound

E86 cluster bomb The E86 cluster bomb was an American biological cluster bomb first developed in 1951. Though the U.S. military intended to procure 6,000 E86s, the program was halted in the first half of the 1950s. History The E86 cluster bomb was developed as a bi ...

.Wheelis, Mark, et al. ''Deadly Cultures: Biological Weapons Since 1945'',
Google Books
, Harvard University Press, 2006, p. 218, ().

Specifications

Similar to the Japanese fire balloon on which its design is based, the E77 utilized a

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...

-filled

balloon A balloon is a flexible bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, and air. For special tasks, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), or light so ...

. Suspended from the balloon envelope was a 32 inch by 24 inch balloon gondola. The E77 was an anti-crop munition, designed to disseminate anti-crop agents, such as

wheat stem rust Stem rust, also known as cereal rust, black rust, red rust or red dust, is caused by the fungus ''Puccinia graminis'', which causes significant disease in cereal crops. Crop species that are affected by the disease include bread wheat, durum w ...

. The balloon bomb employed a dissemination method similar to that of the M115 anti-crop bomb, or "feather bomb". This dissemination method combined a culture of anti-crop agent with a light-weight vector, in this case, feathers.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. O ...

, accessed December 9, 2008.

Tests involving the E77

At least three separate sets of tests were conducted with the E77 balloon bomb. From October to December 1954 41 E77s were launched at

Vernalis, California Vernalis is an unincorporated community in San Joaquin County, California, United States. Vernalis is located on California State Route 33 southeast of Tracy. It was named after two daughters of local ranchers: Verna Carpenter and Alice Hamil ...

, which demonstrated that the munition met "military characteristics" to create high levels of plant infection on targeted crops. Further testing in 1958 showed that when cereal rust spores were delivered via an oil-based vector (wet spores) that they remained viable for longer periods in less than ideal environmental conditions. Subsequent investigations at

Fort Detrick Fort Detrick () is a United States Army Futures Command installation located in Frederick, Maryland. Historically, Fort Detrick was the center of the U.S. biological weapons program from 1943 to 1969. Since the discontinuation of that program, it ...

and the

University of Minnesota The University of Minnesota, formally the University of Minnesota, Twin Cities, (UMN Twin Cities, the U of M, or Minnesota) is a public land-grant research university in the Twin Cities of Minneapolis and Saint Paul, Minnesota, United States. ...

came to several positive conclusions about the effectiveness of oils as carriers of the rust spores.

Background

History

Specifications

Tests involving the E77

See also

References

Further reading