of operations exacted enormous human tolls on the U.S. Army and Marine Corps units mounting first-wave beach assaults (Galston, 2001). At the time, high explosives designed expressly for tree destruction had been used by the military as one tactical option to eliminate the enemy advantage afforded by the dense indigenous vegetation. This tactic was eventually abandoned, as fallen trees could still provide effective cover and concealment for defensive enemy positions along targeted beachheads (Minarik, 1964).

Prior to WWII, the U.S. Army Air Corps had assembled the basic physical apparatus of aerial chemical delivery systems as part of its chemical warfare research and development effort (Buckingham, 1982). Methods for low-altitude application were well beyond preliminary developmental stages, and the atmospheric conditions necessary for the delivery of effective chemical concentrations to targets had also been characterized (Buckingham, 1982). Despite their availability during WWII, aerial chemical delivery systems for herbicide application were not widely implemented in the Pacific theater.2 The technology was, however, employed at many locations including Morotai, Palau, Iwo Jima, and Okinawa in an effort to rid regions of strategic importance of disease-carrying vectors (Cecil, 1986).3 In the 1950s, the British military effectively used aerially disseminated herbicides,4 a fact that did not go unnoticed by U.S. military planners and the State Department as the situation grew more volatile in Southeast Asia (SEA) during the late 1950s and early 1960s (Buckingham, 1997).

By the time President Kennedy took office in 1961, the U.S. military possessed a fairly well-developed arsenal of herbicidal agents. Three years prior to Kennedy’s inauguration, an efficient large-capacity system for the delivery of liquid agents had become standard U.S. Air Force (USAF) inventory (Buckingham, 1982). This system, referred to as the MC-1 Hourglass, comprised a 1,000-gallon tank, pump, and pipe assembly with six nozzles and emergency dumping capabilities (IOM, 1994). The MC-1 was the forerunner of the spray system that was ultimately fitted to the Fairchild C-123s flown in Vietnam.

Meanwhile, in 1959, an H-21 helicopter was successfully used for aerial delivery of herbicides to clear a grove of nuisance sugar maples from an artillery firing range at Camp Drum, New York.5 The herbicide used at Camp Drum was a 50:50 mixture of two phenoxyacetic acids: 2,4-dichlorophenoxyacetic acid

2  

Limited aerial spray tests did occur on some Japanese-controlled islands to demarcate navigation points and to remove dense tropical foliage (Buckingham, 1997).

3  

Vector-borne disease (malaria, dengue, filariasis, and fly-borne dysentery) was the major cause of lost man-hours for the Army Air Corps in the Pacific during WWII. Copper acetate arsenite (Paris Green dust) and dichlorodiphenyltrichloroethane (DDT) were among the insecticides used in the Pacific to destroy adult and larval vector populations (Cecil, 1986).

4  

During the Malayan Emergency (1953–1954) the British used helicopters and some fixed-wing aircraft for successful aerial delivery of sodium arsenate, and later, a mixture of trioxene and diesolene to agricultural targets (Buckingham, 1982).

5  

Known today as Fort Drum.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement