Weather Modification in North Vietnam and Laos Project Popeye
Operation Popeye (also known as Project Popeye) was a highly classified U.S. military weather modification program conducted during the Vietnam War from 1967 to 1972. Executed by the U.S. Air Force’s 54th Weather Reconnaissance Squadron, the operation aimed to extend the monsoon season over the Ho Chi Minh Trail in Laos, North Vietnam, and South Vietnam to disrupt North Vietnamese supply lines.
The program utilized cloud seeding techniques, dispersing silver iodide and lead iodide from aircraft to stimulate rainfall. Official reports claimed the seeding extended the rainy season by 30 to 45 days in targeted areas, resulting in mudslides, washed-out roads, and delayed enemy convoys under the operational slogan “make mud, not war.“
history.state.gov – Weather Modification in North Vietnam and Laos (Project Popeye)
