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)

A woman from a flood affected area arrives to receive food and other items distributed by the religious charity group Al-Khidmat Foundation Pakistan, in Shabqadar near Peshawar, Pakistan, Tuesday, September 13, 2022. The death toll from three months of record-breaking floods in Pakistan rose to over 1,400, officials said Tuesday, as the minister for climate warned the prolonged monsoon rains will continue lashing this impoverished nation in the coming weeks. (Photo by Muhammad Sajjad/AP Photo)

A fan of Canada takes a selfie with former Miss Croatia Ivana Knoll who attends the game during the FIFA World Cup Qatar 2022 Group F match between Croatia and Canada at Khalifa International Stadium on November 27, 2022 in Doha, Qatar. (Photo by Matthew Ashton – AMA/Getty Images)

Members of the Scottish Chinese community take part in Edinburgh Chinese New Year Festival on January 30, 2022 in Edinburgh, Scotland. 2022 marks the Chinese Year of the Tiger, Chinese New Year in Edinburgh has become one of the largest celebrations of its kind in Scotland. (Photo by Jeff J. Mitchell/Getty Images)

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)

Families visit Clifton beach to celebrate the Eid al-Fitr holidays, marking the end of the Islamic holy fasting month of Ramadan, in Karachi, Pakistan, Sunday, April 23, 2023. (Photo by Fareed Khan/AP Photo)

United States' defender Crystal Dunn (R) vies for the ball with Sweden's forward Sofia Jakobsson during the France 2019 Women's World Cup Group F football match between Sweden and USA, on June 20, 2019, at the Oceane Stadium in Le Havre, northwestern France. (Photo by Bernadett Szabo/Reuters)