In the spring of 1965, within weeks of 3,500 American Marines arriving in Vietnam, a 39-year-old Briton named Larry Burrows began work on a feature for LIFE magazine, chronicling the day-to-day experience of U.S. troops on the ground – and in the air – in the midst of the rapidly widening war. The photographs in this gallery focus on a calamitous March 31, 1965, helicopter mission; Burrows’ “report from Da Nang”, featuring his pictures and his personal account of the harrowing operation, was published two weeks later as a now-famous cover story in the April 16, 1965, issue of LIFE.

Photo: Man your battle stations: The crew chief of helicopter Yankee Papa 13, lance corporal James C. Farley, mans an M-60 machine gun during a mission near Da Nang, Vietnam on March 31, 1965. (Photo by Larry Burrows/Time & Life Pictures)

A large Pacific sideband snail slowly crosses a rain wet road in rural Douglas County, Oregon near Elkton on Sunday, December 2, 2012. The moisture loving snail should be very content with the recent heavy rains in southwestern Oregon and northern California. (Photo by Robin Loznak)

Soniya, 6, whose family moved to Islamabad from Pakistan's Khyber-Pakhtunkhwa province to look for work, stands outside their house on the outskirts of Islamabad January 1, 2015. (Photo by Zohra Bensemra/Reuters)

Kim Kardashian filming scenes for Ocean's Eight in Downtown Los Angeles on March 6, 2017. (Photo by Clint Brewer/Splash News and Pictures)

A person looks out at Midtown Manhattan in the haze from the Top of the Rock NYC Observation Deck at Rockefeller Center on June 7, 2023. Smoke from Canada’s wildfires has engulfed the Northeast and Mid-Atlantic regions of the US, raising concerns over the harms of persistent poor air quality. (Photo by Timothy A. Clary/AFP Photo)

Golden State Warriors guard Stephen Curry (30) is flipped upside down after a play during the second quarter against the Sacramento Kings at Golden 1 Center on November 28, 2023 in Sacramento, California. (Photo by Sergio Estrada/USA TODAY Sports)

Turkey and Georgia fans clash before the Euro 2024 Group F match between Turkey and Georgia at the Dortmund BVB Stadion, Dortmund, Germany on June 18, 2024. (Photo by Wolfgang Rattay/Reuters)

Morocco's Hanane Ait El Haj, right, watches as Colombia's Manuela Vanegas, down, challenges Morocco's Sakina Ouzraoui during the Women's World Cup Group H soccer match between Morocco and Colombia in Perth, Australia, Thursday, August 3, 2023. (Photo by Gary Day/AP Photo)