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)

Professional dancer Sandy Lewis, from Louisiana, performs with his dance partner Marti Gasol, as they train in the street due to restrictions to do it indoor, in Barcelona on Wednesday, November 11, 2020 as Spain continue with new measures against the COVID-19. (Photo by Emilio Morenatti/AP Photo)

A woman wearing a mask to help protect against the spread of coronavirus, tries to communicate with Efe, a cat living in Kugulu public garden, in Ankara, Turkey, Monday, November 30, 2020.Turkey's President Recep Tayyip Erdogan has announced Monday the most widespread lockdown so far amid a surge in COVID-19 infections, extending curfews to weeknights and full lockdowns over weekends. (Photo by Burhan Ozbilici/AP Photo)

Goose, a nine-month-old cat, sits in a backpack as people gather during a Speak Out Against Sexual Violence demonstration at Eastern Michigan University in Ypsilanti, Michigan, U.S., March 28, 2021. (Photo by Emily Elconin/Reuters)

A man celebrates the start of the New Year, backdropped by fireworks exploding in the background over Copacabana Beach in Rio de Janeiro, Brazil, Saturday, January 1, 2022. (Photo by Bruna Prado/AP Photo)

Model airplane enthusiasts take part in an event at a model airplane field in Mamak district of Ankara, Turkey on December 30, 2021. Model airplane enthusiasts, each owns different sizes and types of aircrafts, have the opportunity to have fun while training. Weekend meetups also give them an opportunity to help each other on technical issues. (Photo by Dogukan Keskinkilic/Anadolu Agency via Getty Images)

Circus artists perform at the International Circus Show started in Avenue Habib Bourguiba in Tunis, Tunisia on June 23, 2022. (Photo by Yassine Gaidi/Anadolu Agency via Getty Images)

A tiger plays in water at a tiger zoo in Chaing Mai, Thailand on March 31, 2021. (Photo by Soe Zeya Tun/Reuters)