In addition to the factual data provided here and the common opinion, ex post facto, that Operation RANCH HAND seemed like a reasonable idea at the time, but turned out not to be - we should also readily acknowledge the extraordinary contribution made by the U.S. Air Force personnel charged with the duty to carryout the defoliant missions.
The reality of the 10-year program was, only one USAF unit, the 12th Special Operations Squadron, flew these missions. The men assigned to the 12th SOS served in South Vietnam for a year and only had an inkling of what their future service would be like by attending a special "Spray Pilot" class conducted at an auxiliary airfield near Eglin AFB, FL.
The aircraft used for the RANCH HAND program was the Fairchild UC-123K. Except for the very limited usage of this aircraft for defoliant spraying, about 90% of the work done worldwide in the 1960s was hauling troops & cargo within a regional area. The spray equipment was temporary and quite often was removed while in Southeast Asia, so the plane could fly transport missions.
The men coming into the 12th SOS were used to flying a slow, unpressurized, but reliable cargo plane. It was likely the least glamorous flying job in the U.S. Air Force. They were already trained to fly the basic C-123 cargo plane. The primary skills the aircrews learned at Eglin was the unusual task of flying an ungainly cargo plane in wing-tip formation with 2 to 3 other C-123s, and also flying just a few feet above the trees. These were unusual manuevers in a slow cargo plane.
By time the pilots and flight enginners finished spray school after six or so weeks, they thought they were ready to go to Vietnam to kick back for a year in the boring work of crop dusting. The 12th SOS aircrews learned very quickly, however, that crop duster for a year was only the view of someone externally, looking-in on the squadron's operations.
Most spray missions were flown early in the morning, just as the sun came up. Their sorties were pretty short - typically never more than two hours. Their ground speed and spray equipment was such that in a maximum of five minutes the onboard herbicide tank was empty.
All of the 12th crewmen learned very quickly that five minutes of spray-time out of 90 to 120 minutes total flight time was not much...BUT, it was probably the scariest, nerve-wracking five minutes they ever spent in their life! RANCH HAND defoliation was meant to deny dense undergrowth areas to the Communist insurgents - remove their hiding places along roads, rivers, power lines, perimeters around the military bases, etc. Naturally, the enemy didn't like the idea of their hiding places being exposed.
The net result from a spray mission was if there were Viet Cong or NVA troops in the jungle below the spray path, they were going to shoot back at the American planes with their rifles and machine guns. Our troops were not taught to shoot their infantry weapons at aircraft; there usually weren't any. The Communist troops, however, were taught to shoot at low & slow planes & helicopters.
The net result was UC-123K crews wore armored suits in the cockpit and the flight engineer in the back was in an armored booth to operate the spray gear. Their planes were shot at and hit more than any U.S. planes in Vietnam. It was rare to fly a mission without getting hit. They had the most Purple Hearts of any flying unit & were certainly brave men.
Operation Ranch Hand is the name of a U.S. military campaign undertaken during the Vietnam War (1961-75). The campaign involved spraying herbicides, from aircraft, on South Vietnam. Herbicides are chemicals that kill vegetation and defoliate trees (strip them of leaves). In all, approximately 19 million gallons (72 million liters) of herbicides were sprayed over 4 million acres (1.6 million hectares).
The specific herbicides used in Operation Ranch Hand were 2,4-D and 2,4,5-T, collectively known as Agent Orange. (The names 2,4-D and 2,4,5-T refer to the chemical configurations of the molecules.) The name Agent Orange comes from the color-coded drums in which the herbicides were stored.
Operation Ranch Hand officially began in 1962 (although the spraying of Agent Orange, in limited amounts, started in 1961) and continued throughout most of the war. It peaked in the years 1965 to 1967; in 1967 the military was dumping the herbicides faster than manufacturers in the United States could produce them.
One purpose of Operation Ranch Hand was to kill the crops in areas that were inhabited by enemy troops (the Viet Cong), thus depriving them of food. Another was to destroy the dense jungle growth in which Viet Cong troops were hiding.
For the civilian populations of the affected areas, Operation Ranch Hand was nothing short of a campaign of terror. With their food crops destroyed, the villagers were forced to leave their homes. And many people who came into contact with the herbicide developed health problems. Despite repeated promises, the U.S. military never resupplied food to the affected civilian population.
Concerns about the health effects of Agent Orange were initially voiced in 1970 when it was revealed that Agent Orange contained dioxin, a potent carcinogen (cancer-causing agent). Thousands of the U.S. troops who served in Vietnam later developed cancer and many of their children were born with deformities.