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)

Mil Mi-8 combat helicopter flies over Moscow, Russia on May 7, 2019 during the dress rehearsal of a Victory Day air show marking the 74th anniversary of the victory over Nazi Germany in the 1941-1945 Great Patriotic War, the Eastern Front of World War II. (Photo by Sergei Savostyanov/TASS)

A woman reacts with flour over her face while playing a game with cake-making ingredients as part of local festivities marking Myanmar's 70th Independence Day in Yangon on January 4, 2018. The country is celebrating the 70th anniversary of its declaration of independence from British colonial rule. (Photo by Ye Aung Thu/AFP Photo)

Two demonstrators hurl stones at Soviet tanks on Leipziger Platz in East Berlin, Germany on June 17, 1953. Germany's parliament on Friday, June 16, 2023, commemorated the 70th anniversary of a popular uprising in the communist east that was brutally crushed by the Soviet-backed dictatorship.(Photo by AP Photo, File)

North Korean dance during an evening gala as they celebrate the country's 76th founding anniversary at Kim Il Sung Square in Pyongyang, North Korea Sunday, September 8, 2024. (Photo by Jon Chol Jin/AP Photo)

A girl, named Tata and aged 8, wears a Red Army uniform-styled dress during the celebrations of Victory Day, which marks the 78th anniversary of the victory over Nazi Germany in World War Two, in Moscow, Russia on May 9, 2023. (Photo by Shamil Zhumatov/Reuters)

A vendor sells Guy Fawkes masks and items with the colors of the national flag at a market ahead of Independence Day celebrations in Karachi, Pakistan, 13 August 2023. Pakistan celebrates its 76th independence anniversary from British rule in 1947 on 14 August 2023. (Photo by Shahzaib Akber/EPA/EFE)

Members of the Indian Army Service Corps (ASC) team known as the “Tornadoes” display their motorbike skills during Independence Day celebrations in Bangalore, India, 15 August 2023. India is marking the 77th anniversary of its independence from British rule. (Photo by Jagadeesh N.V./EPA)