Operation Popeye

U.S. Air Force cloud-seeding to disrupt supply routes in Vietnam.

Operation Popeye, also known as Sober Popeye, was a secret U.S. Air Force weather modification effort during the Vietnam War from 1967 to 1972. Its aim was to lengthen the monsoon season along the Ho Chi Minh Trail, making roads muddy and triggering landslides to hinder North Vietnamese supply trucks. The program, run from Thailand over Cambodia, Laos, and Vietnam, was reportedly backed by Secretary of State Henry Kissinger and the CIA, without the knowledge of Defense Secretary Melvin Laird, who had told Congress no such tactical weather weapon existed.

Quick Facts

Start date: 20 March 1967
End date: 1972
Operating unit: 54th Weather Reconnaissance Squadron
Aircraft used: C-130 Hercules, F-4C Phantom
Base: Udon Thani Royal Thai Air Force Base, Thailand
Sorties per day: 2
Slogan: make mud, not war

Facts from the source article.

Did You Know?

The operation was also known as Sober Popeye, Project Controlled Weather Popeye, Motorpool, and Intermediary-Compatriot.
The goal was to extend days of rainfall by about 30 to 45 days each monsoon season.
Reporter Jack Anderson published a story in March 1971 about the operation, calling it Intermediary-Compatriot.
The name Operation Popeye entered the public space through a brief mention in the Pentagon Papers and a 3 July 1972 article in the New York Times.
The cloud seeding used lead iodide and silver iodide, developed at Naval Air Weapons Station China Lake and tested in Project Stormfury.

Implementation

The 54th Weather Reconnaissance Squadron carried out the operation using the slogan "make mud, not war." Starting on 20 March 1967, and continuing through every rainy season (March to November) in Southeast Asia until 1972, operational cloud seeding missions were flown. Three C-130 Hercules aircraft and two F-4C Phantom aircraft based at Udon Thani Royal Thai Air Force Base in Thailand flew two sorties per day. The aircraft were officially on weather reconnaissance missions and the aircraft crews as part of their normal duty also generated weather report data. The crews, all from the 54th Weather Reconnaissance Squadron, were rotated into the operation on a regular basis from Guam. Inside the squadron, the rainmaking operations were code-named "Motorpool".