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)

Yan Zhengming (R), 94, and his wife Zhou Suqing (C), 90, attend their wedding ceremony at their home, on the 70th anniversary of their marriage, in Quxian county of Dazhou, Sichuan province, China, May 15, 2015. The wedding, organized by local charity groups, was a long-time wish of veteran of the World War Two Yan, who married Zhou 70 years ago, but could not afford to have a wedding ceremony, local media reported. (Photo by Reuters/Stringer)

LCR Honda IDEMITSU's Japanese rider Takaaki Nakagami crashes in the second MotoGP free practice session of the Portuguese Grand Prix at the Algarve International Circuit in Portimao, on April 16, 2021. (Photo by Patricia de Melo Moreira/AFP Photo)

A ranger watches a seal pup near the Northumberland coast, Farne Islands, UK on December 19, 2018, where the National Trust says the number of Atlantic grey seal pups has reached a record high thanks to an abundance of food and a lack of predators. (Photo by Owen Humphreys/PA Wire Press Association)

Musician St Vincent attends the 90th Annual Academy Awards at Hollywood & Highland Center on March 4, 2018 in Hollywood, California. (Photo by Carlo Allegri/Reuters)

AFC Bournemouth's Marcus Tavernier celebrates scoring their first goal with Adam Smith during the Premier League match between AFC Bournemouth and Fulham FC at Vitality Stadium on April 01, 2023 in Bournemouth, England. (Photo by Paul Childs/Action Images via Reuters)

Mainland Chinese tourists run along a promenade during a typhoon in Hong Kong, Monday, July 17, 2023. Schools and the stock market were closed in Hong Kong on Monday as Typhoon Talim swept south of the city. (Photo by Louise Delmotte/AP Photo)

Australian professional boxer Ebanie Bridges at the weigh-in ahead of their IBF World Bantamweight Title fight against Shannon O'Connell during the weigh in at Aspire, Leeds, United Kingdom on Friday, December 9, 2022. (Photo by Tim Goode/PA Wire)